Almost a hundred years ago, physicists theorized out what free fall should do to a quantum wave. If the solution they came up with is wrong, quantum mechanics and Einstein's theory of gravity flatly contradict each other. But testing it has been impossible because nobody has managed to build an interferometer that could perform the necessary measurement.
Now, a team led by Ron Folman, a physicist at Ben-Gurion University of the Negev, with collaborators in Germany, the UK, and the US, including Nobel laureate Roger Penrose, has done it. They built a new interferometer that gives a single atom two possible paths at once: one that involves a free fall, and another where it is held perfectly still. Both paths end at the same place at the same moment, allowing the team to measure what the fall does to a wave-like property of the atom.
Long time coming
Ever since Galileo, physicists have known how to describe a falling object—where it is, how fast it goes, or how quickly it accelerates. Quantum mechanics, though, insists that every object is also a wave. “Every particle, doesn't matter if it's a car or a spaceship or an atom, is a wave,” Folman says. “Everything that is a wave, like sea waves or sound waves, goes up and down. And if you're up or down, this is measured by something called a phase. A phase just tells you if you are at the top of the wave or at the bottom.”
It turns out Jean-Luc Picard was an even better starship helmsman than the writers knew. A physicist has gone through the details of a warp-speed trick from the first season of Star Trek: The Next Generation and found a subtlety the show missed. But instead of a plot hole, the detail he found actually makes the maneuver more impressive… as well as a great opportunity to teach about a lesser-known feature of the theory of relativity.
Níckolas de Aguiar Alves, a physicist at the Federal University of ABC in Brazil, first watched Next Generation as a master’s student. When he got to the episode "The Battle" in the show’s first season, the plot reminded him of his relativity coursework.
In "The Battle," a Ferengi leader reminds Picard of a battle he fought years ago as captain of a ship called the Stargazer. Under fire from a mysterious attacker, Picard’s ship’s shields were down. He had to get closer without taking a hit, so he made a gamble. Picard ordered the Stargazer to charge the enemy ship at warp speed (meaning faster than light), then stop abruptly and fire. By going faster than light, Picard anticipated that the other ship would see two images of the Stargazer: where it reached warp speed and where it stopped. If they fired on the wrong image, they would miss the Stargazer, and Picard could win the battle.
X-ray: NASA/CXC/Univ. of Alabama/M. Muhibullah et al.; Optical: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/N. Wolk
Using NASA’s Chandra X-ray Observatory, scientists have discovered a new class of objects behaving unlike any they have seen before. Astronomers suggest these newly spotted objects in other galaxies may help solve not one, but two long-standing questions in astrophysics.
These mysterious objects give off unusually low-energy X-rays but intense levels of ultraviolet radiation. This discovery is featured in a paper published Wednesday in Nature Astronomy.
“We’ve never encountered a group of objects that act like this,” said Mustafa Muhibullah of the University of Alabama who led the study. “Of course, the next step was to try to figure out what these things are.”
M101 with illustrated circles calling out seven of the newly-discovered objects.
X-ray: NASA/CXC/Univ. of Alabama/M. Muhibullah et al.; Optical: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/N. Wolk
The researchers found a total of 84 of these “hypersoft X-ray sources” – so named because they give such low-energy X-rays – in the six different galaxies they searched, using data openly available to the public in the Chandra archive. Two of the galaxies are spirals, M31 (the Andromeda galaxy) and M101 (the Pinwheel galaxy), while the other four are ellipticals. They found hypersoft X-ray sources both in regions of active star formation and areas where there are older stars.
The team spotted the sources by finding objects that appeared in Chandra images taken at the lowest X-ray energies but vanished in higher-energy images. That means these objects give off far more low-energy X-rays than high-energy ones. Because low-energy X-rays border energetic ultraviolet radiation on the electromagnetic spectrum, the researchers determined that these sources are producing large amounts of energetic ultraviolet radiation as well.
It is unclear what types of objects are responsible for these low-energy X-rays and intense ultraviolet radiation. The team thinks they most likely involve a black hole, neutron star, or white dwarf pulling material from a companion star. The material pulled from the companion star is heated up to produce X-rays before falling onto the white dwarf or neutron star, or into the black hole. Such binary systems have been seen before, but not with such bright ultraviolet radiation and low-energy X-rays.
The discovery suggests that there may be large populations of binary systems with energetic ultraviolet radiation that have been undetected until now.
“These clandestine X-ray sources are actually among the most energetic objects in galaxies, and they could be solving two cosmic mysteries at once,” said Muhibullah.
Scientists think that some white dwarf systems pulling material from companion stars may eventually explode as a supernova – known as a Type Ia – that is critical for measuring the expansion of the universe. These supernovae played a key role in discovering that this expansion is accelerating. Astronomers have been looking for the stars that turn into Type Ia supernovae for many years, so far without success.
“If we could find a way to spot these Type Ia supernova explosions before they go off, that would be really important,” said co-author Jimmy Irwin, also of the University of Alabama. “Right now, we study them after they’ve exploded, and astronomers have struggled to understand what is actually ignited.”
The other mystery these hypersoft X-ray sources might explain is what strips electrons from gas between the stars in some galaxies. This stripping of electrons is important to probe because it can affect how quickly stars form and influence the life cycles of galaxies. Hot, massive stars play a role, but they do not completely explain what is causing this stripping. The intense levels of ultraviolet radiation from the hypersoft X-ray sources may play a vital role.
Why were these hypersoft X-ray sources not found until now? In addition to the low-energy X-ray output, which is very difficult for X-ray telescopes to detect, the high-energy ultraviolet radiation is readily absorbed by helium and hydrogen gas that fills the space between the stars, creating a nearly impenetrable barrier to look through.
“By combing through the Chandra archive, we were able to eliminate what used to be a blind spot for telescopes,” said co-author Rosanne Di Stefano of the Center for Astrophysics | Harvard & Smithsonian. “That’s how we found what appears to be a new class of cosmic objects with remarkable qualities.”
NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
This release features a composite image of a spiral galaxy, M101; one of six identified galaxies housing a new class of mysterious objects that give off unusually low-energy X-rays.
In this composite image, M101 faces us directly. It has multiple arms in shades of purple, spiraling clockwise around a golden yellow core. Scattered along and between the arms are scores of tiny specks in white and purple. Most of those specks are pairs of stars, but seven of them are a mystery.
To casual observers, the unusual objects are visually indistinguishable from the other specks of light in the galaxy. An annotated version of the composite image is included in this release, with red circles around the mysterious specks for easy identification.
These mystery specks behave like no other class of object discovered before. The curious objects give off X-rays of such low energy, they in fact produce large amounts of ultraviolet radiation, as UV radiation borders X-rays on the electromagnetic spectrum. Searching images of galaxies with low-energy X-rays in the Chandra Observatory archive, scientists have found a total of 84 such objects spread across M101 and five other galaxies. They have dubbed these mysterious objects “hypersoft X-ray sources.”
In 2007, a piece of space debris punched a bullet-like hole through the radiator panel of the US space shuttle Endeavor. The shuttle program ended in 2011, but the space debris problem has only intensified as we launch more and more satellite constellations, telescopes, and spacecraft into orbit. That's why Chinese scientists have devised a new aluminum material inspired by eggshells that they believe could offer enhanced protection against debris fragments, according to a new paper published in the Journal of Applied Physics.
Eggshells have long fascinated scientists because of their mechanical properties. For instance, it's well known that cracking an egg requires applying just enough force to the center to achieve a clean break without completely shattering the shell. In 2012, MIT mechanical engineer Pedro Reis co-authored a paper demonstrating the link between an egg's ovoid geometry and its rigidity, a major factor when predicting how much force an object can endure before cracking. (As I wrote for Slate at the time, rigidity is related to, but distinct from, strength. If one eggshell has tiny cracks and the other doesn't, both shells have different strengths—the cracked one will break more easily—but the same rigidity.)
Reis started studying eggshells after participating in a popular physics demonstration: walking on cartons of eggs without breaking them. The key, he learned, was to align the eggs with their narrow tip (the most crack-resistant part) pointing up, and then carefully place one's feet to distribute one's weight over the entire surface area. This ensures that no single egg is overloaded. While it takes around 5.5 pounds of force to crack an egg, that depends on the direction in which the force is applied, as well as its distribution over the shell's surface.
NASA’s Hubble, Webb Find Far-out Solar System Objects ‘Remember’ Past
This artist’s concept depicts a Trans-Neptunian Object, a small, faint, icy body orbiting the Sun beyond the orbit of Neptune. These objects are so small that even with NASA’s Hubble and Webb space telescopes, they appear only as tiny points of light.
Artwork: NASA, ESA, Leah Hustak (STScI)
For the first time, scientists used the joint power of NASA’s Hubble and James Webb Space Telescopes to study some of the most far-flung bodies in our solar system, Trans-Neptunian Objects (TNOs). Some of these are the smallest and faintest ever directly seen. The researchers unexpectedly found fewer small TNOs than they expected, and that the colors of these bodies followed the same relationships as their larger family members.
These objects are typically small, faint, icy bodies orbiting the Sun beyond the orbit of Neptune. Most are more than 100 million times dimmer than objects visible to the unaided eye. In two complementary papers published Tuesday in The Astronomical Journal, teams analyzed the color, composition, and size distribution of 27 newly discovered tiny, dim TNOs.
This class of small bodies offers the best view into an early stage of planet-building, when a disk of dust and pebbles in orbit around the Sun coalesced into city-sized “planetesimals” — the solid building blocks that clump together to form planets — but had not yet merged into full-sized worlds. Beyond Neptune, this second stage never happened, leaving behind a frozen population of planetesimals.
In the deepest TNO survey to date, teams led by PhD candidates from the University of Victoria in Canada, under the guidance of the National Research Council of Canada, and Northern Arizona University in Flagstaff examined a patch of sky simultaneously with Hubble, observing the TNOs’ visible light, and Webb, observing their infrared light. The team of researchers measured the objects’ colors, which are like a fingerprint of the surface composition, as well as their sizes and determined their orbits.
In the coordinated observations, the teams studied two different types of TNOs. The first, dynamically “cold” TNOs, are on their original, relatively circular orbits around the Sun in the plane of the solar system. The second type, dynamically “hot” TNOs, formed between the current locations of Uranus and Neptune but were pushed outward where they are today when the outer gas giants migrated early in the solar system’s history. Today they reside in highly elliptical orbits and move in and out of the plane of our solar system.
NASA’s Goddard Space Flight Center; Lead Producer: Paul Morris
Prior to these observations, astronomers thought that small TNOs from both hot and cold populations would have undergone many collisions, changing their surfaces compared to larger TNOs. But that’s not what the observations showed. Instead, the small bodies look like their larger counterparts. This implies that collisions are not changing the surfaces significantly—perhaps because there are fewer collisions than expected, or because the TNOs somehow retain their primordial, pre-collision compositions. The teams are still trying to unravel this mystery.
“You could imagine a scenario where getting knocked around and fragmented would change the surface composition, and then you would see a different surface color for tiny TNOs compared to their larger siblings. So it’s really fascinating to see that the smallest objects are somehow ‘remembering’ and preserving the history of how they were made,” said Northern Arizona University PhD candidate Anastasia Morgan, who led the study of color and composition.
“These dynamically ‘hot’ TNOs retain a signature of where they were born, even though they’ve been orbitally scrambled since then,” said co-author David Trilling of Northern Arizona University.
Both the “hot” and “cold” populations seem to keep the same colors as when they were formed, with little change since the birth of the solar system.
The Webb data also allowed researchers to measure the number of objects of each size. They found that the overall size distributions for both populations were surprisingly similar.
“It’s very interesting that the process of planetesimal formation ends up producing the same distribution of sizes for both cold and hot populations, despite forming in different regions of the early solar system. The process seems to be insensitive to disk conditions, producing similar planetesimal sizes whether the disk is hot or cold, and dense or fluffy,” said University of Victoria PhD candidate Marielle Eduardo, who led the study on size distribution.
Researchers also found fewer of these very small bodies than they expected based on some planet formation models. Webb discovered 27 new, remarkably dim TNOs, one so faint it is equivalent to standing on Earth and seeing a small swarm of fireflies on the Moon. The smallest one they observed has a diameter of about 3 miles (5 kilometers), which is about five times smaller than what is possible to detect with the most sensitive ground-based telescopes.
This project would not have been possible without Hubble and Webb working together to detect and characterize these TNOs. With Hubble’s sensitivity in visible light and Webb’s in infrared, the space telescopes provide more insights than either can on its own.
The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
This artist’s concept depicts a Trans-Neptunian Object, a small, faint, icy body orbiting the Sun beyond the orbit of Neptune. These objects are so small that even with NASA’s Hubble and Webb space telescopes, they appear only as tiny points of light.
Tiny Worlds Discovered by Hubble and Webb
This video explains how Hubble and Webb are giving scientists a new look at some of the solar system’s oldest survivors and revealing new clues about how the building blocks of planets, including Earth, first formed.
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NASA’s Hubble Finds Kuiper Belt Duo May Be Trio
A team of researchers found a potential three-body system in the Kuiper Belt. The system, known as the Altjira, challenges traditional collision theories by suggesting that these triple systems might form directly from the gravitational collapse of material in the early solar disk.
NASA’s Webb Reveals the Ancient Surfaces of Trans-Neptunian Objects
Within the first two years of science operations, Webb took high-quality spectra of over 75 TNOs and provided the first comprehensive look at what they are made of.
Uncovering Icy Objects in the Kuiper Belt
Hubble observations of the outskirts of our solar system found a moon orbiting Makemake and several new moons around Pluto. These observations played a critical role in helping NASA plan the New Horizons spacecraft’s flyby of Pluto and beyond.
Hubble Harvests Distant Solar System Objects
Astronomers using clever techniques to cull the data archives of NASA’s Hubble Space Telescope have added 14 new TNOs to the catalog.
Kuiper Belt: Exploration
The Kuiper Belt is a doughnut-shaped region of icy objects beyond the orbit of Neptune. It is home to Pluto and most of the known dwarf planets and some comets.
It's that time of year again, when we learn which lucky scientists are among the winners of the Ig Nobel Prizes. This year, the prizes honor research on designing the perfect splash-free urinal; using mosquito proboscises to "necroprint" tiny nozzles; studying composition rates of buried cotton underwear; and the aerodynamics of a healthy nose-blow, among other highlights.
Established in 1991, the Ig Nobels are a good-natured parody of the Nobel Prizes; they honor “achievements that first make people laugh and then make them think.” The unapologetically campy awards ceremony features miniature operas, scientific demos, and "24/7 lectures," whereby experts must explain their work twice: once in 24 seconds and the second in just seven words.
Acceptance speeches are limited to 60 seconds. And as the motto implies, the research being honored might seem ridiculous at first glance, but that doesn’t mean it’s devoid of scientific merit. In the weeks following the ceremony, the winners will also give free public talks, which will be posted on the Improbable Research website.
This Hubble Space Telescope image features the picturesque nebula LHA 120-N44, or N44.
NASA, ESA/Hubble, D. Gouliermis
This NASA/ESA Hubble Space Telescope image features a sprawling cosmic vista in the Large Magellanic Cloud, or LMC, the largest of the small galaxies that orbit our Milky Way galaxy. At just 160,000 light-years away, the LMC offers a close look at highly active star birth sites like the one in this image. This photogenic nebula, named LHA 120-N44, or N44, is in the constellation Dorado.
N44 is dominated by two features: a vast central void and a shell of dense, dusty gas. The central void is a ‘superbubble’ spanning roughly 210 by 140 light-years across. The glittering stars at the center of the void are responsible for its creation; through their powerful stellar winds and explosive supernovae, these stars expelled much of the gas from which they were born.
When the stars of N44’s central star cluster swept away this gas, the expelled gas compressed and formed a shell around the superbubble. New stars are forming in this compressed gas shell, making N44 an interesting target for astronomers who are using the nebula to study how stars form in this environment. Their goal is to understand how long it takes from the collapse of cold gas clouds into dense knots to the moment nuclear fusion ignites in the heart of a newborn star.
The data in this image is from an observing program (#14689; PI: Gouliermis) that used Hubble to survey N44 and take a census of its stars, cataloging nearly half a million stars within the cluster as well as interlopers drifting in front of it. Of the stars surveyed, nearly 30,000 are what astronomers call pre-main-sequence stars, which have yet to begin fusing hydrogen into helium in their cores. Astronomers discovered this treasure trove of baby stars thanks to the high sensitivity and fine spatial resolution of Hubble’s instruments that can pick out faint objects in crowded clusters.
The gas shell surrounding the superbubble is energized by ultraviolet radiation from massive stars, causing it to glow and highlighting several distinct features. Each feature within the broader N44 star-forming complex was cataloged by astronomer Karl Henize in the 1950s. One feature is a smaller bubble, cataloged as N44F, that is located near the upper-right corner of this image. N44F is an interstellar bubble blown by the intense stellar winds of a single hot and massive star. As this previously released Hubble closeup shows, the star’s furious winds and radiation have sculpted the surrounding bubble and created pillars of dusty gas.
Hubble’s sensitive observations of the lowest-mass stars in this region open a new window onto star formation in regions that, like the LMC or the galaxies in the early universe, are poor in elements heavier than helium.
In this YouTube video, Dr. Ken Carpenter takes us on a journey through the Nebula, teaching us some of the interesting science behind this famous Hubble image.
Hubble Views N44 Superbubble
N44 is a complex nebula filled with glowing hydrogen gas, dark lanes of dust, massive stars, and many populations of stars of different ages. One of its most distinctive features, however, is the dark, starry gap called a “superbubble,” visible in this Hubble image in the upper central region.
Large N44 Mosaic Image
Download various sizes of Hubble’s large N44 mosaic, including a high resolution, 14,478 x 19,908 pixel (1.6 GB) image
NASA’s Hubble Tracks New Decagon Encircling Saturn’s South Pole
Recent NASA Hubble Space Telescope images show the gas giant Saturn and its southern pole, where astronomers have discovered a 10-sided atmospheric wave. Observations show the decagon extends through multiple layers of Saturn’s atmosphere.
Image: NASA, ESA, STScI, Agustin Sánchez-Lavega (UPV), Amy Simon (NASA-GSFC), Michael Wong (UC Berkeley); Image Processing: Alyssa Pagan
Recent observations with NASA’s Hubble Space Telescope have revealed a giant, evolving, 10-sided atmospheric wave encircling Saturn’s south pole. This discovery marks the first time a large, regular-sided jet pattern has been observed in the planet’s southern hemisphere. The feature appears remarkably similar to Saturn’s famous hexagon at its northern pole, but is also distinctly different, suggesting scientists may be witnessing a new atmospheric phenomenon develop on the iconic gas giant.
The results published Wednesday in the journal Science Advances.
By piecing together several years of Hubble observations dating back to 2023, researchers found subtle hints of the structure beginning to emerge before it became a clearly defined pattern. Those observations were taken as part of Hubble’s Outer Planet Atmospheres Legacy (OPAL) program, which has photographed the outer planets annually for more than a decade.
“We’ve never seen anything quite like this in Saturn’s southern hemisphere,” said Amy Simon, study co-author and OPAL principal investigator, NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The northern hexagon has been there every time we’ve looked for more than 40 years. This feature is different — it appears to be strengthening, giving us the rare opportunity to watch a giant atmospheric pattern develop.”
The discovery was possible because Saturn’s changing seasons gradually brought the planet’s south pole back into view from Earth, where astronomers who collectively analyze images of Saturn from ground-based observatories first identified it.
Agustín Sánchez-Lavega, lead author of the new study, is a researcher at the University of the Basque Country in Spain. The university manages a website, called Planetary Virtual Observatory Laboratory, that accepts ground-based images of solar system planets contributed by observers all over the world. It was in those images, first in 2024, that Sánchez-Lavega and amateur astronomers Trevor Barry and Jean-Paul Oger noticed a subtle undulating band along the southern pole. Additional 2025 imagery taken from the ground hinted even more strongly toward this decagon structure.
That’s when the Hubble observations come into the picture. Hubble’s view from space offers unmatched image sharpness and spatial resolution over full rotations of Saturn, without smearing by Earth’s atmosphere.
“Given Saturn’s symmetry in its north-south jet stream system, we have been searching for a counterpart to Saturn’s northern hexagon on the south pole in Hubble images since 1990,” Sánchez-Lavega said. “Images from NASA’s Cassini spacecraft, which orbited Saturn between 2004 and 2017, showed no inkling of a long-lived formation, either. The Hubble data confirmed the feature’s presence back to 2023.”
A single filter from NASA’s Hubble Space Telescope distinctly shows a 10-sided wave encircling Saturn’s south pole, labeled “decagon”. An “X” denotes where data was not captured.
Image: NASA, ESA, STScI, Agustin Sánchez-Lavega (UPV), Amy Simon (NASA-GSFC), Michael Wong (UC Berkeley); Image Processing: Alyssa Pagan
The wave sits within one of Saturn’s powerful jet streams and extends through multiple layers of the atmosphere, indicating it is not just a cloud-level feature, but a vertically extended atmospheric structure. The decagon’s apparent position shifts slightly, because Hubble captures images from different wavelengths. Those different wavelengths probe different altitudes in Saturn’s atmosphere.
“The most intriguing part to me is that this seems to have just formed recently,” said Simon. “The question is, why did it suddenly form now when we haven’t seen one before?”
The authors say further study is needed from Hubble and NASA’s James Webb Space Telescope, as well as analysis of computer models, to understand how the decagon formed, how long it may last, and how it compares to the long-lived hexagon in the north.
Hubble’s long duration in operation has allowed astronomers to track changes over time in solar system planets and other astronomical objects as well.
Rather than providing a single snapshot, the OPAL program allows scientists to follow seasonal changes, track short-lived storms, and identify other atmospheric features that evolve slowly over time.
“When we started the OPAL program, we expected compelling surprises, but we didn’t know what to expect specifically,” said Mike Wong, study co-author, University of California, Berkeley. “A lot of the discoveries we see coming from OPAL are not just based on one observation, but on years and years of data. Regular observations over time are enabling a lot of new findings.”
The team plans to continue observing Saturn to determine whether the decagon settles into a long-lived, stable configuration like the northern hexagon or continues to evolve. Future observations also could help scientists determine what drives the wave, what it reveals about the atmospheric dynamics of giant planets throughout the solar system, and how they may relate to those we see here on Earth.
The Hubble Space Telescope has been operating for more than three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
Recent NASA Hubble Space Telescope images show the gas giant Saturn and its southern pole, where astronomers have discovered a 10-sided atmospheric wave. Observations show the decagon extends through multiple layers of Saturn’s atmosphere.
Decagon on Saturn’s South Pole (Single Filter)
A single filter from NASA’s Hubble Space Telescope distinctly shows a 10-sided wave encircling Saturn’s south pole, labeled “decagon”. An “X” denotes where data was not captured.
High above Earth, thin veils of metallic haze drift through the edge of space. Known as sporadic E layers, these high-altitude “clouds” form from the vaporized dust of burnt-up meteors, earning their name from the unpredictable way they emerge and then dissipate. Now, new results from a NASA sounding rocket — a suborbital research rocket — that flew five detectors through one of these layers simultaneously reveal unexpected complexity in the layer for the first time.
Though invisible to the eye, sporadic E layers make their presence known to the radio signals we rely on for long-distance communication. When present, sporadic E can send those signals ping-ponging off in unexpected directions, rendering the technology temporarily unreliable.
Scientists have long sought a fuller understanding of these radio-disrupting clouds, but until recently, they had only sampled them one narrow slice at a time. The rocket, called the sporadic E Electrodynamics Demonstration, or SpEED Demon for short, launched from NASA’s Wallops Flight Facility in Virginia on Aug. 24, 2022, and demonstrated the first concurrent, multi-point view inside sporadic E. Its results, from a team led by Embry-Riddle Aeronautical University, are described in a new study in the Journal of Geophysical Research: Space Physics.
Sporadic E layers form in the ionosphere, a region of the upper atmosphere beginning around 40 miles (60 kilometers) up where the neutral gases begin to transform into plasma, or ionized gas. Some of the particles there come from meteors, which burn up and leave behind traces of iron, magnesium, and other metals. These metals occasionally clump into dense, cloud-like sheets — the sporadic E layers — that reflect radio waves.
An animated illustration depicts Sporadic-E layers forming in the lower portions of the ionosphere, causing radio signals to reflect back to Earth before reaching higher layers of the ionosphere.
NASA’s Goddard Space Flight Center/Conceptual Image Lab
“Sporadic E layers are, in one sense, giant mirrors of radio frequency waves in the sky,” said Aroh Barjatya, the mission’s principal investigator and a professor of engineering physics at Embry-Riddle in Daytona Beach, Florida.
When a sporadic E layer forms, signals meant to travel out to space can ricochet back toward the ground. Air traffic controllers and marine radio users may pick up distant transmissions as though they were nearby, and radars scanning beyond the horizon can register so-called “ghosts,” or false targets. The effects reach everyday technology, too.
“The biggest source of error in the GPS in your phone, for example, is from the plasma in the ionosphere, and sporadic E layers can contribute to this uncertainty,” said Henry Valentine, the study’s lead author, who conducted the work at Embry-Riddle and is now a researcher at the U.S. Naval Research Laboratory.
Because sporadic E layers hover around 60 miles (100 kilometers) up—too high for weather balloons, too low for satellites — and form and dissipate unpredictably, they have long been the province of sounding rockets, which can be launched on short notice to catch one in the act. But a single rocket flies a single path, taking measurements only along a line. Barjatya likens the situation to viewing a scene through a crack in a wall. One can only observe what is happening along that narrow slit, missing out on the crucial context of whatever is occurring to the left or right of one’s view.
The SpEED Demon mission changed that. The mission was the first to deploy ejectable probes, called dropsondes, inside a sporadic E layer. Once inside, the rocket released four dropsondes that flew away from the main payload and from one another, each measuring the plasma along its own track and beaming its measurements back to ground stations. Together with the main payload, the probes sampled the layer in a total of five places at the same moment.
The SpEED Demon team poses with payload section during testing at NASA’s Wallops Flight Facility.
NASA Wallops/Berit Bland
“Now with multiple sensors, we’ve turned that crack into a picket fence,” Barjatya said.
The data revealed surprising complexity inside the sporadic E layer. Rather than a smooth, dense pancake of metallic particles, the layer that SpEED Demon flew through appeared uneven and structured, shaped by turbulent winds moving through the neutral air around it.
“A lot of times you think of sporadic E as this single sharp density layer, but what we saw in ours is it’s interacting with neutral wind and these swirling atmospheric turbulences,” Valentine said. “Rather than a flat pancake, it’s closer to a cinnamon roll.”
On the way down, the layer even split into two distinct peaks. The team found that shape was consistent with modulation by Kelvin-Helmholtz billows, the curling, wave-like instability that produces breaking-wave patterns in ordinary clouds. Because the flight was unable to measure the local winds and electric fields directly, the researchers are careful to call the billow explanation plausible rather than confirmed.
The SpEED Demon mission was designed as a technology demonstration — a test of whether the dropsonde technique would work at all. It did, and the team was quick to apply it again. Barjatya’s team used a similar multi-probe strategy to launch rockets into the paths of the October 2023 annular eclipse and April 2024 total solar eclipse, studying how the sudden darkness disturbed the upper atmosphere. In June 2025, they flew SpEED Demon’s most direct descendant, Sporadic-E ElectroDynamics, or SEED, into sporadic E layers from Kwajalein Atoll in the Marshall Islands, studying them at lower latitudes. Papers from those missions are in preparation.
A sounding rocket launch testing science instruments for future missions was successfully conducted at 9:16 p.m. EDT, Aug. 23, 2022, from NASA Wallops Flight Facility in Virginia.
NASA
After years of study, sporadic E layers are no longer as unpredictable as they once were. “They have a seasonality to them, with peak occurrence happening in the local summer,” Barjatya said.
Questions about how and when they form are increasingly fine-grained. The new deployable multi-point rocket sensor methodology, along with ground-based measurements, is likely to bring the picture even closer to completion. “The science community as a whole is now in its final stretches of fully understanding these giant radio frequency mirrors in the sky,” Barjatya said.
ByMiles Hatfield NASA’s Goddard Space Flight Center, Greenbelt, Md.
It’s a regrettable reality that there is never enough time to cover all the interesting scientific stories we come across. So every month, we highlight a handful of the best stories that nearly slipped through the cracks. August’s list includes the discovery of a new celestial object astronomers have dubbed a "black hole star"; breaking down plastics with microbes and turning them into edible cookies; how whale calls are connected to Einstein's special theory of relativity; and how avocado tree flowers switch sex during the day, among other highlights.
Discovery of a "black hole star"
Credit:
Rohan Naidu (University of Hawai'i)
In 2024, astronomers combing through datasets taken by the James Webb Space Telescope noticed hundreds of mysterious little red dots lurking therein, believed to be baby quasars. They existed when the Universe was just a few hundred million years old. One such object in particular captured scientists' interest: a red dot that was extremely red and very bright, but whose properties didn't fit with any known astrophysical object. Astronomers have now concluded that the little red dot is a "black hole star," so named because it is the size of a large star but produces far more energy than would be possible via nuclear fusion—energy comparable to what an active black hole would produce.
A SpaceX Falcon Heavy rocket with NASA’s Nancy Grace Roman Telescope on board is seen transiting the sun during launch from Launch Complex 39A, Sunday, Aug. 30, 2026, at NASA’s Kennedy Space Center in Florida.
NASA/John Kraus
Now on a three-month, million-mile journey to its final orbit, NASA’s Nancy Grace Roman Space Telescope will soon reveal the universe’s darkest secrets. The mission launched at 7:26 a.m. EDT Sunday aboard a SpaceX Falcon Heavy rocket from Launch Complex 39A at the agency’s Kennedy Space Center in Florida.
Roman pairs a large field of view with crisp infrared vision to explore vast swaths of the sky and probe deeply into cosmic history. This flagship mission will help astronomers explore dark matter, dark energy, and worlds outside of our solar system, known as exoplanets. Its surveys will support a broad range of research extending far beyond the mission’s main science goals.
“Roman is exactly the kind of success story we want to see across NASA,” said NASA Administrator Jared Isaacman. “Delivered ahead of schedule and on budget, this mission reflects more than a decade of dedication from the NASA workforce and our industry partners. Now, Roman will give us a new atlas of the universe, push the boundaries of discovery, and demonstrate what is possible when America’s space program pairs bold ambition with disciplined execution.”
The ground control team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, began receiving telemetry data from Roman seven minutes after launch. The Falcon Heavy rocket performed as expected, separating from the observatory 31 minutes into the flight. After separating from the center core, the rocket’s boosters safely returned to the launch site for refurbishment.
“Roman will be a discovery machine that will bring us closer than ever before to answering humanity’s most profound questions about our cosmic history,” said Nicky Fox, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “With its large field of view and fast survey speeds, Roman will usher us into a new era of discovery and make the invisible visible, setting the foundation for humanity’s search for life beyond our solar system.”
During launch and early orbit, Roman uses the Near Space Network’s ground stations and relay satellites to exchange tracking, telemetry, and command data with ground controllers. About 70 minutes after launch, the Deep Space Network takes over communications and guides Roman toward the second Sun-Earth Lagrange point, or L2, about one million miles from Earth. Roman connects to that network through the Canberra Deep Space Communication Complex in Australia first. Approximately six hours later it will transfer to the Madrid Deep Space Communication Complex in Spain and then to the Goldstone Deep Space Communication Complex in California, ensuring continuous contact with Roman throughout its journey.
The Roman team also confirmed successful deployment of the observatory’s solar panels and lower instrument sun shade an hour and 23 minutes after launch. Within the upcoming days, Roman’s high-gain antenna and visor-like deployable aperture cover will deploy, ground controllers will initiate the first of two-mid-course corrections, and the Coronagraph Instrument will power on. This instrument will demonstrate the technology that future missions like NASA’s Habitable Worlds Observatory concept could use to image Earth-like planets in the search for life in the universe. Roman’s Coronagraph will take a giant step in that direction by snapping pictures of Jupiter-like planets.
A few weeks into Roman’s voyage, its primary instrument, the Wide Field Instrument, will activate. This 300-megapixel infrared camera has 18 4K detectors, each about the size of a saltine cracker. These detectors collect photons of light that will be decoded into crisp cosmic panoramas. Thanks to the observatory’s rigid design and stable optical performance, it will rapidly scan the sky without needing substantial time between separate observations. The Roman telescope is designed to survey the universe a thousand times faster than NASA’s Hubble Space Telescope.
Throughout the rest of Roman’s three-month commissioning period, scientists will run the instruments through a series of calibrations and tests. NASA anticipates releasing Roman’s first images by early 2027.
Roman will send back 1.4 terabytes of data every day, the highest data rate of any NASA astrophysics mission, so far. Machine learning, artificial intelligence, and citizen scientists will help sift through it and flag significant findings, which astronomers can then study.
“We’ve never been able to view the universe with eyes like Roman’s before,” said Julie McEnery, Roman’s senior project scientist at NASA Goddard. “There’s no telling what more we’ll know and have seen by this time next year.”
Roman is the fourth primary mission NASA has launched on a Falcon Heavy rocket. Earlier this year, the agency’s Launch Services Program worked with SpaceX to accelerate the launch date to accommodate the space telescope’s early completion.
The telescope is managed at NASA Goddard with participation by the agency’s Jet Propulsion Laboratory in Southern California; Caltech/IPAC in Pasadena, California; the Space Telescope Science Institute in Baltimore; and a team of scientists from various research institutions. The primary industrial partners are BAE Systems Inc., L3Harris Technologies, and Teledyne Scientific & Imaging. Contributions to Roman also are made by ESA, JAXA, the French space agency CNES (Centre National d’Études Spatiales), and the Max Planck Institute for Astronomy in Germany.
NASA’s Pandora Mission Begins Study of Exoplanets, Host Stars
Pandora, NASA’s newest exoplanet mission and the first satellite to launch through the agency’s Astrophysics Pioneers program, is now making unique observations of worlds beyond our solar system and the stars they orbit. The mission will determine the atmospheric make-up of at least 20 exoplanets, including the presence of hazes, clouds, and water.
“Pandora’s data will help close a major gap in our knowledge about planets and their host stars because, right now, we can’t be entirely sure how the star’s light affects measurements of what makes up exoplanet atmospheres,” said Elisa Quintana, Pandora’s principal investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We designed the Pandora spacecraft and its in-depth observing program to better understand this vexing issue.”
Artist’s concept of NASA’s Pandora mission, which will help scientists untangle the signals from exoplanets’ atmospheres and their stars.
NASA’s Goddard Space Flight Center/Conceptual Image Lab
The results of the mission will lay a firm foundation for interpreting measurements by NASA’s James Webb Space Telescope, as well as future observatories focused on finding habitable worlds. In fact, Pandora’s near-infrared detector is a spare originally developed for Webb.
“The spacecraft is healthy and all of the instruments are performing as well as we could have hoped,” said Jordan Karburn, Pandora’s deputy project manager at Lawrence Livermore National Laboratory in California. “Our team’s hard work throughout the commissioning process has paid off, and we can now confidently start science.”
This artist’s concept summarizes NASA’s Pandora mission and its science goals. Pandora will repeatedly observe multiple planets and their host stars in both visible and near-infrared light. These measurements will enable astronomers to separate chemical fingerprints detected in a planet’s atmosphere from potentially misleading signals originating from its host star.
Launched into low Earth orbit on Jan. 11, Pandora is an ambitious small satellite (SmallSat) funded by NASA’s Astrophysics Pioneers program. Pioneers are designed to explore compelling questions about the universe with fast-paced, low-cost missions that require a higher-than-usual tolerance for failure.
Three factors make Pandora unique. It carries a novel all-aluminum telescope about 18 inches (45 centimeters) in diameter, it will study planets and their host stars simultaneously in both visible and infrared light, and it will observe targets for a much longer time than flagship observatories like Webb are able to.
Telescopes can sample a planet’s atmosphere in systems where the planet passes in front of its star as seen from our perspective. During this event, called a transit, some starlight skims the planet’s atmosphere before making its way to us. As this light interacts with atmospheric molecules, their chemical fingerprints become embedded in it. For each molecule, astronomers see brightness dips at characteristic wavelengths.
But our instruments also see light from the whole star, not just what grazes the planet. Stellar surfaces aren’t uniform. They sport hotter, brighter areas called faculae and cooler, darker regions similar to sunspots. Both can grow, shrink, and change position as the star rotates.
“Water is one of the most important molecules we can measure to understand the composition and physical conditions of an exoplanet atmosphere,” said Benjamin Rackham, a team member at the Massachusetts Institute of Technology in Cambridge. “But features on the star can distort the water signal we’re searching for. Pandora is designed to disentangle the signals from the planet and the star, helping us to understand the planets more accurately and laying the groundwork for the eventual study of planets that could harbor life.”
Watch to learn more about NASA’s Pandora mission, which will revolutionize the study of exoplanet atmospheres. NASA’s Goddard Space Flight Center
Pandora’s telescope, jointly developed by Livermore and Corning Specialty Materials in Keene, New Hampshire, and its detectors make up the mission’s heart. The detectors will capture the star’s brightness in visible light and its near-infrared spectrum at the same time, while also obtaining a near-infrared spectrum from the planet when it transits the star. Over the course of its year-long primary mission, Pandora will observe at least 20 exoplanets 10 times with a long-duration stare covering 24 hours, with a transit included in each observation.
“Pandora’s advantage is its ability to observe targets for extended periods at multiple wavelengths, something high-demand flagship missions like Webb cannot regularly do,” said Knicole Colón, the mission’s project scientist at NASA Goddard. “Combining Pandora and Webb data will uniquely enable scientists to determine the properties of stellar surfaces and cleanly separate star and planetary signals.”
Pandora is led by NASA’s Goddard Space Flight Center. Lawrence Livermore National Laboratory provides the mission’s project management and engineering. Pandora’s telescope was manufactured by Corning and developed collaboratively with Livermore, which also developed the imaging detector assemblies, the mission’s control electronics, and all supporting thermal and mechanical subsystems. The infrared sensor was provided by NASA Goddard. Blue Canyon Technologies provided the bus, performed spacecraft assembly, integration and environmental testing, and is providing mission operations support. NASA’s Ames Research Center in California’s Silicon Valley performs the mission’s data processing. Pandora’s science data is available at the NASA Exoplanet Archive, which is operated by IPAC at the California Institute of Technology in Pasadena. The University of Arizona leads mission operations for Pandora and contributes to its science program. Many additional universities also support the science team.
To learn more about the Pandora mission, please visit:
Galactic Gems Glisten in New Gallery From NASA’s Chandra
Galaxies are like cosmic gems, each with characteristics including size and shape that make them distinct. A new gallery released today from NASA’s Chandra X-ray Observatory and other telescopes displays a collection of galactic images that showcase this variety.
Astronomers put galaxies into three main categories: spirals like our own Milky Way with arms emanating from their cores, ellipticals that are older and likely the results of mergers, and irregulars that can encompass a wide range of galactic phenomena.
This gallery displays a collection of 16 galactic images from Chandra and other telescopes. Astronomers put galaxies into three main categories: spirals like our own Milky Way, ellipticals that are older and likely the results of mergers, and irregulars that can encompass a wide range of galactic phenomena. All types are represented in this collection. Each galactic image contains X-ray data from Chandra combined with data from telescopes such as NASA’s Webb, Hubble, IXPE, Swift, and NuSTAR, and others both in space and on the ground.
Just as gems reveal the history of Earth through how they were forged over billions of years, these galactic gems are a way to study Earth’s place in our home galaxy of the Milky Way. By looking outward to other galaxies, we learn more about our own – including clues to its past and future.
There are 16 new images in this galactic gallery. Each one contains X-ray data from Chandra that has been collected across Chandra’s decades in space. This high-energy data has been combined with data from telescopes such as NASA’s James Webb and Hubble Space Telescopes, IXPE (Imaging X-ray Polarimetry Explorer), Neil Gehrels Swift Observatory, NuSTAR (Nuclear Spectroscopic Telescope Array), and others both on the ground and in space.
NGC 1672
A barred spiral galaxy featuring a prominent central bar or bridge of stars that channels gas toward its core. Chandra X-rays (purple) highlight growing black holes along the bar and core, merged with Hubble optical light (white, yellow and soft blue) and JWST infrared dust filaments (red). Studying barred spirals in action can help reveal how gas in our own Milky Way, which is also a barred spiral, feeds its central black hole and forms new stars.
X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI/Hubble Heritage Team; Infrared: NASA/ESA/CSA/STScI/J. Lee and T. Williams; Image Processing: NASA/CXC/SAO/L. Frattare, J. Major, K. Arcand
II Zw 096
A chaotic, dust-shrouded system of merging galaxies forming stars at a furious rate. Chandra X-ray data (magenta) pinpoint powerful black hole activity and hot gas, while Hubble optical (blue and white) and Webb infrared (red and grey) data illuminate vast stellar nurseries hidden behind interstellar dust. Systems like II Zw 096 show us how powerful galaxy collisions shaped the early universe.
X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI; Infrared: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare and J. Major
M33
A nearby, face-on spiral galaxy whose clear spiral arms offer an unhindered view of its stellar engine. X-ray data from Chandra (purple) highlights point sources like neutron stars and stellar-mass black holes pulling material off companion stars (systems called X-ray binaries), while optical data from the Very Large Telescope’s MUSE instrument (pink and grey) maps glowing pockets of hydrogen gas. Ultraviolet data from NASA’s Swift telescope (blue) reveals populations of young, massive stars sizzling across the spiral arms. M33’s proximity to us allows astronomers to audit individual high-energy objects and map how stellar feedback affects a galaxy’s ecosystem.
A spiral galaxy famous for having two extra, “anomalous” spiral arms composed of hot gas. Chandra’s X-rays (royal blue) show superheated shockwaves created by central black hole jets, combined with optical light from Hubble (red, yellow and pale blue) and infrared dust filaments from Webb (bright orange). M106 helps show how supermassive black holes can create structural features that mimic star-bearing spiral arms, influencing a galaxy’s evolution.
A compact dwarf irregular galaxy undergoing a violent, compact burst of star formation. Chandra and XMM-Newton observations (blue and purple) reveal massive bubbles of million-degree gas inflated by stellar winds, set against a backdrop of optical light (magenta, orange and white) imaged by Adam Block. Dwarf starburst galaxies can serve as local laboratories for studying the conditions of the early universe, where small, primitive galaxies formed stars at frantic rates.
A large spiral galaxy that is being stripped of its gas as it plunges at high speed through hot gas in the Virgo Cluster of galaxies. Chandra’s X-ray data (magenta) pinpoints high-energy point sources—such as X-ray binaries and supernova remnants—and diffuse hot gas nestled within the spiral disk imaged by Hubble (blue, brown and gold). A ground-based optical light image taken from New Mexico by Timothy Martin reveals red filaments of hydrogen gas streaming over 300,000 light-years behind the galaxy as it falls into the Virgo Cluster.
A giant elliptical galaxy undergoing a dusty merger, featuring a powerful jet of particles blasting tens of thousands of light-years into space. Chandra’s X-rays (blue) showcase the high-energy jet, with additional X-rays from IXPE (orange), while Webb infrared (magenta) and optical light (amber and white) from the European Southern Observatory expose a dark, churning dust lane. As one of the closest active galaxies to Earth, Cen A allows astronomers to study the effects of supermassive black hole jets in extraordinary detail.
X-ray: (Chandra) NASA/CXC/SAO, X-ray (IXPE): NASA/MSFC; Optical: ESO; Infrared: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare, K. Arcand, and J. Major
M104
Famous for its broad central bulge and dark outer dust ring, this galaxy sits at a nearly edge-on tilt to Earth. Chandra X-rays (cyan and orange) isolate compact point sources and hot gas in the galaxy’s sprawling halo, merged with Hubble optical light (warm white) and Webb infrared vision (purple-red dust lane). Studying M104 may help bridge the gap between spirals and ellipticals, helping astronomers better understand how a galaxy’s giant outer cloud of stars grows and ages alongside its inner disk.
This ring galaxy system formed when a smaller companion galaxy punched straight through its center like a bullseye, creating a powerful cosmic shockwave. Chandra X-rays (purple) uncover bright X-ray binary systems scattered along the collision shock wave, laid over Hubble’s optical image (blue and white) of expanding stellar rings. Such head-on collisions can trigger vast ripple effects, sparking huge waves of star birth across entire galaxies.
A “one-armed” barred spiral galaxy surrounded by a prominent star-forming ring. Chandra’s X-ray data (magenta) pinpoints several bright X-ray sources, likely caused by growing black holes, embedded within the sweeping optical disk (soft blue and white) captured with the Mt. Lemmon Observatory. Galaxies with unusual single arms can offer a window into how the gravity from a passing galaxy can trigger bursts of star formation.
A barred spiral galaxy packed with regions where stars are actively forming. Chandra X-ray data (magenta) highlights stellar nurseries and X-ray binaries scattered along dusty spiral structures brought to life by Hubble optical (white and grey) and Webb infrared (orange and red) observations. Comparing multiwavelength data of barred spirals containing active star formation helps scientists map how local starbursts build up galactic mass over time.
A rare “polar ring” galaxy where a tilted outer ring of stars and dust rotates over the galaxy’s poles, an unusual structure likely caused by a collision with another galaxy about a billion years ago. Chandra’s X-rays (purple) reveal a possible growing supermassive black hole in the center of the galaxy, plus X-ray binaries nestled within the stars and dust captured by the Gemini Observatory in optical light (gold, blue and white). Studying polar rings teaches us about the diverse effects of stellar collisions on the shapes of galaxies.
An irregular galaxy undergoing intense star formation because of a gravitational interaction with a neighboring galaxy hundreds of millions of years ago. Chandra X-rays (blue), supplemented by NuSTAR data, show towering superwinds of million-degree gas blowing thousands of light-years out of the galactic disk, with Hubble optical light (yellow, orange and white) showing the galaxy shape, and Webb and Spitzer detailing infrared dust emission (red). M82 was nicknamed the Cigar Galaxy mostly because of its edge-on angle to Earth, which makes its central disk look like an elongated, cigar-shaped oval with small optical telescopes. The galaxy illustrates how violent galactic “exhaust systems” can regulate a galaxy’s growth by venting gas outwards.
X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI; Infrared: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare, J. Major, and K. Arcand
NGC 3256
A pair of colliding, gas-rich spiral galaxies merging into a single massive system. Chandra’s X-ray data (pink) isolates point sources and shock-heated gas, Hubble’s optical light (blue and white) captures tidal tails of stars, and Webb’s infrared vision (red and orange) cuts through the dust to show hidden star formation. Galaxy collisions like this offer a preview of our far future, showing what might happen if our own Milky Way collides and merges with the nearby Andromeda Galaxy.
A face-on spiral galaxy whose orientation gives us an unobstructed view of its disk. X-ray emissions from Chandra (magenta) detail energetic X-ray binaries and supernova remnants scattered across dust lanes in an optical image (white, blue and gold) from Adam Block with Mt. Lemmon Observatory. Face-on orientations are important for galactic studies because they provide the most unobstructed views of a galaxy’s stars and gas.
X-ray: NASA/CXC/SAO; Optical: Adam Block/Mount Lemmon SkyCenter/University of Arizona; Image Processing: NASA/CXC/SAO/L. Frattare
NGC 4631
A spiral galaxy viewed from its side, featuring a giant halo of hot gas blowing out of its stellar disk. X-rays from Chandra and ESA’s XMM-Newton (purple and royal blue) trace hot gas driven out by supernovas and black holes and neutron stars pulling gas from their companions, while optical light (light blue, gold and white) from ground-based observer R. Jay GaBany showcases dense dust lanes. Edge-on views of galaxies allow astronomers to study how flat their stellar disks are and provide the clearest views of material located above or below the disk.
X-rays are critical for the study of galaxies, revealing unique and important information about these cosmic building blocks. For example, Chandra exposes gas that has been superheated to millions of degrees by winds from massive stars, the outflows from supermassive black holes, and the debris from exploded stars. These are key sources of elements in our bodies, in the air we breathe, and the planet we live on. Chandra also sees some of the hottest and most energetic galactic phenomena in the universe, forming a more complete picture of how galaxies live, interact, and evolve when combined with data from other types of light and telescopes.
Spiral and star-forming engines
Face-on spiral galaxies like Messier 33 and NGC 3938 offer unobstructed views of places where energetic pairs of stars and cosmic explosions live along spiral arms. Barred spirals like NGC 1672 and NGC 1385 show how central bar-shaped collections of stars, gas, and dust funnel fuel inward to ignite bursts of star formation. NGC 4725 reveals how star formation can be triggered by a previous collision with another galaxy. Meanwhile, edge-on views of NGC 4631 (the Whale Galaxy) and the starburst Messier 82 (the Cigar Galaxy) showcase giant halos and superwinds of million-degree gas driven thousands of light-years into space by intense explosions of stars, enriching surrounding intergalactic space with vital elements.
Active galactic nuclei, black hole outflows
Powerful, growing black holes in the cores of their host galaxies, known as active galactic nuclei, send energy outward in outbursts and jets that impact entire galaxies. In Centaurus A, Chandra and IXPE data expose a high-energy particle jet blasting tens of thousands of light-years into space from its central engine. In Messier 106, jets from the supermassive black hole heat surrounding gas to create spiral arms that are different from those typically found in spiral galaxies. Meanwhile, the iconic Sombrero Galaxy (Messier 104) highlights a supermassive black hole embedded in a colossal stellar bulge, where Chandra’s X-rays map a diffuse halo of million-degree gas and hot stellar remnants surrounding its sweeping dust lanes.
Collisions, mergers, cosmic disruptions
The gallery also showcases galaxies undergoing extreme gravitational transformations. A direct impact in Arp 143 acts like a cosmic bullseye, creating an expanding ring galaxy and triggering waves of star birth. Violent mergers, such as NGC 3256 and the dust-shrouded starburst II Zw 096, reveal the kind of chaotic galaxy collisions that dominated the early universe and offer a preview of the Milky Way’s distant future merger with nearby galaxy Andromeda. NGC 1569 acts as a local laboratory for studying early universe starbursts, NGC 660 showcases a rare “polar ring” galaxy where a ring of stars orbits over its poles, and Messier 90 shows a spiral galaxy plowing through the Virgo Cluster, having its star-forming gas violently stripped away.
NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
Starstruck: NASA Research Shows How Sun’s Ancient History Shaped Earth
At the center of our solar system, the Sun influences every planet that orbits it. In two recent NASA-funded studies, scientists uncovered how ancient events in the Sun’s history may have helped create Earth’s unique climate and driven previously unexplained climatic shifts.
In new research, scientists at NASA’s SHIELD (Solar Wind with Hydrogen Ion charge Exchange and Large-Scale Dynamics) center — one of NASA’s DRIVE (Diversify, Realize, Integrate, Venture, Educate) Science Centers — trace the trajectory of the heliosphere, the massive bubble created by our Sun that envelops our solar system, as it moved through our galaxy and influenced Earth’s climate along the way. In another paper, a NASA scientist and coauthors investigate how the younger, dimmer Sun managed to heat Earth by seeding the production of potent greenhouse gases.
A Sun on the move
Over the last tens of millions of years, Earth’s climate has undergone significant shifts, including notable ice ages in which the global average temperature temporarily dropped by several degrees. During these periods, more frequent climate swings led Earth to warm and cool. To explain these periods of warming and cooling, scientists looked to factors internal to Earth, including orbital changes, greenhouse gases, and ice. But new research suggests changes to the Sun’s environment may be key to understanding Earth’s temperature swings.
Just as our planet is encased by an atmosphere, so our entire solar system is encased inside a kind of “atmosphere” created by the Sun. This protective bubble, known as the heliosphere, is formed by a continuous solar wind of charged particles streaming out from the Sun in all directions.
This conceptual animation begins with a view of the Milky Way Galaxy. As we zoom in, we travel to the Local Interstellar Cloud, and then to the heliosphere, the protective bubble that surrounds our solar system. The heliosphere is formed by a continuous stream of charged particles from the Sun, called the solar wind.
NASA’s Goddard Space Flight Center Conceptual Image Lab
Our heliosphere orbits around the center of our galaxy, the Milky Way. Throughout the Sun’s 4.6-billion-year existence, our heliosphere has traversed various regions within our galaxy. In a paper published on Aug. 21 in Annual Review of Astronomy and Astrophysics, researchers at NASA’s SHIELD used computer modeling to reverse-engineer the path of the heliosphere through our galaxy, revealing that the environments it passed through may have triggered changes on Earth.
Merav Opher, SHIELD’s principal investigator at Boston University, and her team ran simulations that showed the Sun has encountered frigid expanses of gas and dust at least three different times in the past few million years. In these instances, massive interstellar “cold clouds” pushed against the heliosphere to such an extent that it shrank to smaller than Earth’s orbit, stranding our planet outside the Sun’s protective shield.
These exposures — approximately 2 to 3 million years, 6 to 7 million years, and 13 to 14 million years ago — would have exposed Earth’s atmosphere to totally different surroundings. The simulation results match geologic evidence: Elements prevalent in interstellar dust appear in deep-sea sediment core samples, Antarctic snow, and lunar samples during these timelines.
This animated illustration shows Earth and the Sun protected by the heliosphere, the massive bubble created by our Sun. As our solar system traverses through the galaxy, encounters with massive interstellar “cold clouds” pushed against the heliosphere and caused the heliosphere to shrink past Earth, exposing the planet to cosmic radiation and elements from interstellar space.
NASA’s SHIELD DRIVE Science Center/Merav Opher/Harvard Radcliffe Institute
These heliosphere collapse events may also explain ancient climatic patterns on Earth. In the simulations, when Earth’s atmosphere was exposed to a cold, dense galactic hydrogen cloud, it increased water vapor content and shifted upper-atmospheric dynamics, ultimately altering the conditions at the surface. In summary, our heliosphere’s trips through colder regions in our galaxy may be a key factor in driving some of Earth’s ancient changes in climate, including possible ice ages.
Next frontier in studying heliophysics
The SHIELD center is one of several that NASA funds to unlock the next generation of heliospheric research. As a DRIVE Science Center, SHIELD builds a team of researchers with differing expertise, approaches, and opinions to develop a model, or “digital twin,” of the heliosphere that helps reveal how the heliosphere interacts with its surroundings, including dense interstellar clouds. Understanding our unique, habitable solar system will help unravel the mysteries of life’s evolution on Earth and potentially uncover other habitable star systems.
Young Sun
In another paper, Vladimir Airapetian, a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, focuses on a long-standing mystery of how the ancient Sun warmed early Earth enough to sustain life. Three billion years ago, the young Sun was 70% as bright as it is today. Under these dimmer conditions, Earth should have been frozen solid. Yet geological evidence shows stable liquid water already existed long before that. This puzzle — a balmy Earth under a cooler, dimmer Sun — is known as the Faint Young Sun paradox.
One clue to resolving the paradox comes from young Sun-like stars elsewhere in the galaxy. These “toddler” stars are prone to throwing fits. Specifically, data from NASA’s retired Kepler space telescope shows that young Sun-like stars regularly erupt with massive superflares, flinging high-energy particles in all directions on a daily basis. If our young Sun was like these other stars, Airapetian proposes, the barrage of high-energy solar particles could have triggered chemical reactions that were key to warming early Earth.
Airapetian’s team simulated early Earth’s atmosphere in a sealed chamber, mixing molecular nitrogen, ammonia, carbon dioxide, and carbon monoxide. They then fired protons into the mixture, simulating the onslaught of particles from superflares. This proton bombardment triggered several changes including the production of nitrous oxide, a greenhouse gas 300 times more potent than carbon dioxide. The research was published in Astrophysical Journal Letters.
This nitrous oxide could help Earth hold onto heat. But not all the nitrous oxide would last. The young Sun’s intense ultraviolet radiation would break some of it down, splitting the molecule back into nitrogen and oxygen. But even if only 10% of the nitrous observed in the experiment survived, Airapetian’s team’s computer simulations confirmed, it would still warm Earth’s equatorial regions to about 41 degrees Fahrenheit (5 degrees Celsius), above water’s freezing point. This smaller amount of nitrous could even accelerate prebiotic synthesis: just-above-freezing temperatures have been found to be more efficient for building complex chains of amino acids than warmer temperatures.
Unearthing secrets of our star-planet system
Together, these two studies show that the Sun can lead to surprising implications for Earth. While our planet stands alone in many ways, it was formed and has always existed as part of a star-planet system. Understanding that unique relationship promises new insights about both Earth and the star that sustains it.
NASA Shares Views of August Solar Eclipse from Ground, Air, Space
This composite image shows the progression of a total solar eclipse as the Sun sets over San Millán de los Caballeros, Spain, on Wednesday, Aug. 12, 2026.
Credits: NASA/Bill Ingalls
On Aug. 12, a total solar eclipse darkened skies over Greenland, Iceland, and Spain. As the Moon covered the Sun, it briefly revealed the Sun’s wispy outer atmosphere — the corona — to those in the path of totality who were lucky enough to have clear skies. NASA researchers and photographers were along the eclipse path to study the corona, capture the phenomenon, and observe how the eclipse affected our planet.
One NASA photographer in Spain captured the total solar eclipse as well as the partial phases before and after, until the Sun set below the horizon.
This composite image shows the progression of a total solar eclipse over a field of sunflowers in San Millán de los Caballeros, Spain, on Aug. 12, 2026. Credit: NASA/Bill Ingalls
The solar corona appears in this photograph of a total solar eclipse captured from San Millán de los Caballeros, Spain, on Aug. 12, 2026. Credit: NASA/Bill Ingalls
A solar prominence, a plume of electrically charged gas suspended above the Sun by strong magnetic forces, appears as a pink feature along the left edge of the eclipsed Sun in this photograph taken from San Millán de los Caballeros, Spain, on Aug. 12, 2026. Credit: NASA/Bill Ingalls
This composite image shows the progression of a total solar eclipse as the Sun sets in San Millán de los Caballeros, Spain, on Aug. 12, 2026. Credit: NASA/Bill Ingalls
In northern Maine, where only a partial eclipse was visible, another NASA photographer captured the International Space Station, with its crew of seven aboard, speeding past the partially eclipsed Sun.
In this image of a partial solar eclipse, which is veiled by clouds, the International Space Station, with a crew of seven aboard, appears in silhouette as it transits at roughly five miles per second on Aug. 12, 2026, as seen near Hodgdon, Maine. Aboard the station as part of Expedition 75 are NASA astronauts Jessica Meir, Anil Menon, and Jack Hathaway; ESA (European Space Agency) astronaut Sophie Adenot; and Roscosmos cosmonauts Pyotr Dubrov, Andrey Fedyaev, and Anna Kikina. Credit: NASA/Joel Kowsky
Twelve frames assembled in sequence show the International Space Station, with a crew of seven aboard, in silhouette as it transits the Sun at roughly five miles per second during a partial solar eclipse on Aug. 12, 2026, as seen near Hodgdon, Maine. Clouds partially obscure the view of the Sun. Aboard the station as part of Expedition 75 are NASA astronauts Jessica Meir, Anil Menon, and Jack Hathaway; ESA (European Space Agency) astronaut Sophie Adenot; and Roscosmos cosmonauts Pyotr Dubrov, Andrey Fedyaev, and Anna Kikina. Credit: NASA/Joel Kowsky
Meanwhile, from about 250 miles above the ground, a NASA astronaut aboard the International Space Station snapped a few photos of the partial eclipse from their perspective as well.
NASA astronaut Jessica Meir captured this photo of the partial solar eclipse from the International Space Station on Aug. 12, 2026, as the orbital outpost soared 262 miles above southern Quebec, Canada. From the station, the Moon covered about 18% of the Sun at the peak of the eclipse. Credit: NASA/Jessica Meir
Between the ground and the space station, NASA pilots flew NASA’s WB-57F research jet at an altitude of 50,000 feet, passing through the eclipse’s shadow to lengthen their time in the eclipse. The jet carried a suite of cameras that captured high-resolution images of the corona and prominences, plumes of electrically charged gas rising off the Sun, in several different wavelengths of light.
The total solar eclipse on Aug. 12, 2026, was captured by a camera mounted inside the cockpit window of NASA’s WB-57F aircraft as it flew around 50,000 feet altitude off the coast of Iceland.
NASA
A suite of cameras installed on NASA’s WB-57F aircraft captured images of the solar corona and prominences in different wavelengths of visible and infrared light during the total solar eclipse on Aug. 12, 2026. A science team led by the Southwest Research Institute in Boulder, Colorado, will analyze the images to learn more about complex and dynamic features in the Sun’s outer atmosphere. Credit: NASA/SwRI/Will Ashfield
In both Iceland and Spain, teams of students participating in the NASA-funded Nationwide Eclipse Ballooning Project launched scientific balloons that carried instruments to capture images of the eclipse’s shadow and study the eclipse’s effects on our atmosphere. Even though clouds obscured the view of the eclipse from the ground in Iceland, the weather did not interfere with the balloon-borne instruments’ ability to gather information about how the brief loss of light and heat affected the lower atmosphere.
Students participating in the NASA-funded Nationwide Eclipse Ballooning Project prepare to launch a scientific balloon in Mosfellsbær, Iceland, during the total solar eclipse on Aug. 12, 2026. Credit: NASA/Abbey Interrante
The Moon’s shadow passes over the atmosphere during the total solar eclipse on Aug. 12, 2026. The video was taken by a camera carried by a scientific balloon launched from Spain by a student team from Montana State University participating in the NASA-funded Nationwide Eclipse Ballooning Project. The video captures about six minutes of time but is sped up to play at four times real speed. Passing through the foreground are some other science instruments carried by the same balloon.
Nationwide Eclipse Ballooning Project/Montana State University
Before the eclipse, scientists at Predictive Science Inc., with support from NASA grants and supercomputers, used observations of the Sun from NASA spacecraft and ground-based telescopes to predict what the corona would look like during the eclipse. Below, their corona prediction is compared to a composite image of the corona, which combines multiple images captured by the NASA-supported DEB Initiative project during the total eclipse near León, Spain.
prediction
image
This image shows a prediction from the morning of Aug. 12, 2026, of what the solar corona would look like to the human eye during the total solar eclipse that day.
Predictive Science Inc.
This processed, composite image of the corona combines multiple images captured near León, Spain, during the total solar eclipse on Aug. 12, 2026.
DEB Initiative Team/Zack Stockbridge
This image shows a prediction from the morning of Aug. 12, 2026, of what the solar corona would look like to the human eye during the total solar eclipse that day.
Predictive Science Inc.
This processed, composite image of the corona combines multiple images captured near León, Spain, during the total solar eclipse on Aug. 12, 2026.
DEB Initiative Team/Zack Stockbridge
prediction
image
The left image shows a prediction from the morning of Aug. 12, 2026, of what the solar corona would look like to the human eye during the total solar eclipse that day. The right image is processed, composite image of the corona that combines multiple images captured near León, Spain, during the total solar eclipse on Aug. 12, 2026. Left image credit: Predictive Science Inc.; right image credit: DEB Initiative Team/Zack Stockbridge
Over the coming months, scientists will analyze the observations and images captured during the solar eclipse on Aug. 12 and present what they have learned about the Sun and its effects on our home planet. These observations will also help prepare science teams to investigate future solar eclipses, such as a much longer total solar eclipse that will be visible from southern Spain and northern Africa on Aug. 2, 2027.
This image was taken by an Artemis II astronaut from the Orion capsule in April 2026, as the spacecraft traveled past the Moon and back over 10 days. The gray-brown, heavily cratered Moon dominates the frame against black space, with a partially lit crescent Earth setting behind its upper-left edge.
Some of Earth’s microbes likely to hitch a ride to space with human explorers could survive in the shaded nooks and crannies of the Moon’s South Pole region, NASA scientists say.
Published on Aug. 19, 2026, in Science Advances, these findings highlight a need to better understand microbial persistence in extreme lunar environments. As humans build a permanent presence on the Moon, it may become difficult to distinguish ancient lunar chemistry from contamination delivered by visiting astronauts. The concern extends beyond the Moon and on to Mars, scientists say.
“Humans are natural explorers, and with them come their voices, their memories … and their microbes,” said Prabal Saxena, a planetary scientist who led the study from NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “For some scientists, myself included, that reality can be unsettling. But it also creates an opportunity to turn an imperfect situation into a useful experiment.”
Bringing microbes along is unavoidable: Humans have, on average, 1 million bacteria living on each patch of skin the size of a pencil eraser, for example. These bacteria vent from spacesuits and habitats. Though the paper’s authors worry about contamination interfering with the search for chemical clues to ancient geology or biology, they also argue that the Moon should be used as a natural lab. In shaded areas around the South Pole, scientists could carefully test the real-life limits of microbial survival in an environment that can’t easily be reproduced on Earth.
The Apollo program landed six pairs of astronauts on the Moon between 1969 and 1972. All six landing sites are near the lunar equator. In this visualization, the Apollo sites are contrasted with the South Pole, an area with enormous potential for future exploration. Time passes as we zoom toward Shackleton crater at the South Pole, revealing illumination conditions quite different from those near the equator. While many craters remain in permanent shadow, some nearby mountains and ridges are in persistent sunshine, making them attractive candidates for solar power and long-term habitation.
Before any surface science can happen, scientists need a baseline measurement of what contaminants humans bring, the authors say.
“We need to understand what was there before us, because when we go to Mars to search for signs of life beyond our planet, we will want to make sure it’s not stuff we brought,” said Andrew Needham, a NASA Goddard-based paper co-author who is an Artemis contamination‑control scientist for lunar samples.
Even with strict sterilization procedures, some organisms are stubbornly resilient. A good example is Aspergillus niger, which is a fungus that thrives in warm, damp places like household bathrooms and heating, ventilation, and air conditioning systems. Astronauts have sampled it inside the International Space Station, and experiments demonstrate that the fungus can survive outside the station as well. Aspergillus niger was one of five microbes, including bacteria and fungi, selected for this study because of its known toughness in spaceflight environments.
That microbes survived on the space station’s exterior surprised scientists. These species are typically not considered “extremophiles” that can withstand harsh conditions, such as the vacuum of space, according to Aaron Regberg, a geomicrobiologist at NASA’s Johnson Space Center in Houston.
“I would have expected these microbes to have dried out,” said Regberg, who studies space station bacteria and was a co-author on the paper.
NASA astronaut Kate Rubins on Oct. 14, 2016, collecting microbes in the Japanese Experiment Module aboard the International Space Station.
JAXA/Takuya Onishi
He pointed out that NASA often bakes robotic spacecraft at temperatures above 400 degrees Fahrenheit to reduce the number of living organisms on them. But that’s not possible with astronauts, so contamination concerns take on new meaning in crewed exploration of the Moon’s south polar environment.
A clearer picture of where microbes might survive comes from understanding how sunlight behaves at the poles. Survival in this study means the microbe can stay alive for at least one Earth day, which does not mean that it can grow and reproduce.
Because the Moon has a very small tilt on its axis, the view from its poles is of a Sun that appears to hover just above the horizon, skimming the surface like a flashlight laying on a table. As a result, elevated parts of the surface, including crater ridges, mountains, and even small bumps, block light from reaching low-lying terrain. This produces pockets of shadowed areas that can remain cold and preserve water, as well as shield fragile molecules and possible microorganisms from lethal radiation.
With that scientific context in mind, the team set out to test which Earth microbes could survive extreme polar conditions. They focused on organisms commonly found in spaceflight environments and those common on human skin. Besides Aspergillus niger, these included Bacillus subtilis, Staphylococcus aureus, Deinococcus radiodurans, and several species of Fusarium. Based on an analysis of previous studies, the scientists noted the maximum amount of heat and ultraviolet (UV) radiation each organism can withstand.
Then, the organisms were tested in simulations of three regions near the lunar South Pole — Nobile Rim, Connecting Ridge, and De Gerlache Rim. Those simulations used detailed environmental maps built from elevation and temperature data collected by instruments aboard NASA’s Lunar Reconnaissance Orbiter, combined with models of how radiation strikes the surface.
The models showed maps of “survivable niches” that range in size from a miles-wide crater floor to an astronaut’s boot print. Aspergillus niger, which was most resistant to UV radiation, was able to survive even in areas with some sunlight exposure. UV radiation is so deadly to most microbes that it’s used for sterilization in hospitals.
“When we think of the Moon, we don’t typically think of biology,” said Heather Graham, a paper co-author at NASA Goddard who helps develop tools and techniques for detecting biology that may look nothing like Earth’s. “But the Moon is a place where a cell can survive, so our first exploration of these sites should pay extra attention to our microbial hitchhikers and work hard to characterize lunar chemistry before our visits change what we will find.”
The authors note that while some microbes can survive in a dormant state in regions around the South Pole, and thereby confuse some future scientific investigations, there is no evidence the Moon has key ingredients to sustain growth and replication. Such ingredients include liquid water, which typically requires an atmosphere and moderate temperatures.
International Observe the Moon Night, Sept. 19, 2026
Each year, observers around the world come together to celebrate Earth’s Moon through direct observations, hands-on activities, lunar-themed music, artwork, readings, and more.
The Moon
From lighting up our skies to preserving evidence of our solar system’s history, Earth’s closest neighbor plays a pivotal role in the study of our planet and beyond.
About the Author
Lonnie Shekhtman
Senior Science Writer
Shekhtman helps communicate NASA planetary science to the world through news and feature stories on NASA.gov, videos for NASA+ and YouTube, and by working with the media. She reports on lunar and Mars science and exploration; NASA’s search for life; missions to Venus, Titan, and Jupiter’s Trojan asteroids; and many other topics related to NASA’s exploration of our solar system and beyond.
Hubble Solves Merger Mystery From Milky Way’s Early Years
About 12 billion years ago, a dwarf galaxy known as LKH collided with a young Milky Way and merged with it. This artist’s concept portrays that collision. NASA’s Hubble Space Telescope uncovered definitive evidence of this collision by studying globular star clusters.
Illustration: NASA, ESA, Joseph Olmsted (STScI)
Our home galaxy, the Milky Way, grew to its current size in part by consuming smaller galaxies. Now, new data from NASA’s Hubble Space Telescope shows definitive evidence of a dwarf galaxy merging with the young Milky Way galaxy in the earliest phases of its evolution. This finding extends our knowledge of our galaxy’s history 1.8 billion years farther back in time than before.
The Milky Way today is a massive spiral galaxy home to hundreds of billions of stars. However, our galaxy wasn’t always so large; it has grown by forming new stars from its gas clouds as well as collecting stars, gas, and dark matter from other galaxies through mergers.
The most recent massive merger in our galaxy’s history took place with the Sagittarius dwarf galaxy, beginning over 6 billion years ago and still ongoing today. Looking back into the even more distant past, researchers learned that the Milky Way galaxy consumed another dwarf galaxy called Gaia-Sausage-Enceladus 10 billion years ago. This ancient merger greatly affected the structure of our galaxy’s disk of stars. Other, smaller mergers occurred between these two.
But our galaxy’s history doesn’t stop there. Both observations and simulations have suggested that another large merger preceded these two, though the specifics of the event have been heavily debated. Now, Hubble has uncovered definitive evidence of an earlier merger that occurred about 11.8 billion years ago, or just 2 billion years after the big bang.
“Our home is the Milky Way galaxy, but we do not know how our house was built,” said Davide Massari, lead author, Astrophysics and Space Science Observatory of Bologna in Italy. “In this paper we discover where the first significant batch of bricks came from: a dwarf galaxy that we call LKH.”
Cosmic archaeological sites
Immense astronomical surveys and precision data from spacecraft like ESA’s (European Space Agency’s) Gaia mission have been instrumental in piecing together the history of our galaxy. The farther back into our galaxy’s history that scientists attempt to look, the more difficult it becomes to tell what happened. When our galaxy was young, it was smaller and much closer in size to the galaxies it clashed with. It was also more chaotic, and it’s possible that the signs of mergers have been erased over billions of years.
It’s into this murky past that Hubble peered. Researchers used Hubble to study some of the Milky Way galaxy’s globular clusters: immense, roughly spherical collections of tens of thousands to a few million stars. Globular clusters contain some of the oldest stars in our galaxy, and they can act as cosmic archaeological sites that preserve stars from other galaxies the Milky Way galaxy has collected.
“Thanks to the high resolution and depth of Hubble imaging, we could measure the age and the metal content of these clusters with unprecedented precision,” said Chiara Zerbinati, study co-author, University of Bologna in Italy. “Coupled with measurements from Gaia, this made it possible to distinguish a population of globular clusters that are different from the others. These are the clusters that were born in LKH, and they tell us when that galaxy was devoured by ours, and how massive it was.”
The team analyzed Hubble observations of 39 globular clusters in the inner 20,000 light-years of our galaxy, where evidence of the most ancient mergers should be preserved. They expected this sample to contain globular clusters that formed within the young Milky Way galaxy as well as those collected from the Gaia-Sausage-Enceladus dwarf galaxy about 10 billion years ago.
Using Hubble’s sensitive observations to determine each cluster’s precise age and associated metallicity — the abundance of elements heavier than helium — they determined there was a third population of globular clusters in the inner regions of our galaxy. The team found that these clusters are older than the group collected in the Gaia-Sausage-Enceladus merger, but younger than those born in the Milky Way, regardless of their metal content. These clusters, therefore, came from a separate and even earlier merger — in which the Milky Way galaxy absorbed a dwarf galaxy containing roughly 500 million times the mass of the Sun in stars, a significant fraction of our galaxy’s mass at the time. They named this dwarf galaxy Low-energy-Kraken-Heracles, or LKH, in honor of three earlier research papers that championed the idea of a merger early in our galaxy’s history.
Such a large merger so early in the Milky Way galaxy’s formation has profound implications for the evolution of our galaxy.
“Some past studies have argued that the earliest phases of our galaxy’s evolution were defined by stars born only in our galaxy,” says Massari. “Here, we have shown that stars born in external galaxies also need to be considered.”
The team plans to continue their work to unravel the history of the Milky Way galaxy by studying its globular clusters, aiming to characterize all the massive mergers that our galaxy has experienced across cosmic history.
“Hubble is observing globular clusters that have never been studied before, and this will help us characterize the merger events that are far back in time in the Milky Way galaxy’s history,” said Fernando Aguado-Agelet, co-author, University of Vigo and the University of La Laguna in Spain.
The Hubble Space Telescope has been operating for more than three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
About 12 billion years ago, a dwarf galaxy known as LKH collided with a young Milky Way and merged with it. This artist’s concept portrays that collision. NASA’s Hubble Space Telescope uncovered definitive evidence of this collision by studying globular star clusters.
NASA’s COFFIES Uses AI to Predict Storm-Causing Active Regions on Sun
As humanity looks to the Moon and stars for future exploration, predicting space weather — conditions in space primarily driven by the Sun — is more important than ever.
Now, a team of astrophysicists and data scientists with NASA’s COFFIES (Consequence Of Fields and Flows in the Interior and Exterior of the Sun) has developed a novel machine-learning model capable of predicting the emergence of active regions on the Sun up to 12 hours before they appear.
The Sun is constantly churning. Intense concentrations of localized magnetic fields can suddenly break through the solar surface, forming sunspots. Space weather forecasters then collectively number and track sunspots since they are visible manifestations of active regions, which serve as the main engines behind severe space weather events such as solar flares and coronal mass ejections. These eruptions send waves of high-energy radiation and charged particles across space, creating storms that can threaten astronauts, disable satellites, and disrupt radio communications on Earth.
NASA’s Solar Dynamics Observatory captured this image of a solar flare — seen as the bright flash in the upper right — on June 30, 2026. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is colorized in teal.
NASA’s Goddard Space Flight Center/SDO
By bridging expertise across different scientific institutions, COFFIES, a NASA DRIVE (Diversify, Realize, Integrate, Venture, Educate) Science Center, brought together a team of researchers from New Jersey Institute of Technology (NJIT), Princeton University, and NASA’s Ames Research Center in California’s Silicon Valley. The team turned to advanced artificial intelligence architectures — which dictate how data is processed and used to produce reliable predictions or actions — to capture subtle, time-based pattern changes on the solar surface before an active region took shape. By analyzing data captured by the agency’s Solar Dynamics Observatory and using NASA Ames’ supercomputing resources, this new approach, published in the Journal of Geophysical Research: Machine Learning and Computation, looks at fluctuations in acoustic waves caused by sunspot regions when the regions form beneath the solar surface and begin the journey upward to emerge on the surface.
“We cannot directly see the magnetic structure while it is still rising through the solar interior. Instead, we must look for indirect effects — very small changes in the magnetic field and in the pattern of acoustic waves continually traveling through the Sun,” said Alexander Kosovichev, a COFFIES co-investigator at NJIT. “The developed technique identifies precursors associated with an emerging active region in slight changes of the Sun’s acoustic power — more like a slight change in rhythm within a very noisy orchestra.”
This video is an example of what scientists use when analyzing the solar surface. This particular time frame tracks the magnetic field on the Sun’s surface during the emergence of active region AR11158 in February 2011. The blue square grid highlights a target area on the Sun. The squares on the right side translates the data from the target grid area to show opposing magnetic polarities, indicated by the warm and cool-colored tones. The first column of blocks shows targeted areas at original resolution, the middle column displays data as 2D maps, and the right column plots changes in magnetic polarity over time as 1D curves. By watching these blocks, scientists can see signs of active region emergence, such as drops in acoustic waves and rises in magnetic fields.
NASA’s COFFIES DRIVE Science Center/Irina Kitiashvili and Spiridon Kasapis
To develop current operational forecasts, the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center and the United States Air Force monitor active regions that are already visible on the Sun to analyze the regions’ characteristics and estimate the probability of solar flares.
The COFFIES team aims to revolutionize this process. The AI model the team developed a specialized early detection system to handle very long sequences of data — called sliding-window transformer architecture — to use observations to find tiny reductions in the Sun’s acoustic activity and magnetic field, signals that scientists struggled to capture until now. These reductions form patterns that the AI model uses to predict active regions several hours before they become visible on the solar surface. Instead of looking at all activity on the solar surface at once, like earlier deep learning approaches have done, this new model moves a fixed-size “viewing window” across a long timeline of the Sun’s activity to focus on recent data while remembering overall patterns. This method allows forecasters the ability to predict approximate locations of emerging sunspots, rather than relying on counting already visible sunspots.
This promising AI architecture shows how deep machine learning can contribute to heliophysics — the field studying the nature of the Sun and how it influences the very nature of space and the planets that exist there. While the model is not ready for operational real-time forecasting, the team plans to validate the approach across many more known solar events to fine-tune the model.
NASA’s real-time space weather monitoring
As NASA focuses on sending humans to explore the Moon with the Artemis missions and sending the first crewed missions to Mars, monitoring and forecasting space weather is important for ensuring the safety of our astronauts and the equipment they rely on. This predictive leap from the COFFIES team could prove vital for safeguarding technology and deep-space explorers from the volatile environment of our solar system.
NASA’s Moon to Mars Space Weather Analysis Office monitors space weather 7 days a week. This important work helps decision makers not only protect people and equipment but maintain the services our modern society relies on every day. NASA’s space weather monitoring is also critical for safeguarding astronauts as they journey to the Moon and onward to Mars.
NASA/Lacey Young
Teams across NASA and NOAA collaborate to transition research capabilities into actual 360-degree space weather monitoring operational tools — including NASA’s Space Radiation Analysis Group, Moon to Mars Space Weather Analysis Office (M2M SWAO), and Community Coordinated Modeling Center as well as NOAA’s Space Weather Prediction Center. Sunspot region emergence prediction capabilities, especially of the Sun’s far side, could provide new information that supplements current models used by these teams.
“The COFFIES AI model is exciting to our team because it could provide us with new capabilities towards predicting potential flaring locations ahead of time,” said Michelangelo Romano, M2M SWAO deputy director. “With this heads up, we can provide additional support to NASA missions.”
NASA’s COFFIES is one of three DRIVE Science Centers created to encourage collaborative science by establishing centers that are made of multidisciplinary teams from several institutions across the U.S. These pioneering facilities employ modelers, theoreticians, computer scientists, and observers to study important mysteries of our star and its influence, a branch of science known as heliophysics.
The COFFIES team focuses on the interconnected processes behind the Sun’s activity. Understanding the Sun’s interior and magnetic variability is key to advancing our understanding of the Sun’s 11-year activity cycle and fine-tuning space weather forecasting tools.
The fully-integrated LEMS (Lunar Environment Monitoring Station) ready for environmental testing. A small suitcase-size instrument suite built at NASA Goddard, LEMS is designed to carry out continuous, long-term monitoring of the seismic environment at the Moon, including surface motion caused by moonquakes and meteorite impacts in the lunar south polar region.
NASA Goddard/Mike Guinto
NASA has declared “wrenches down” on the first completed payload designed for Artemis astronauts to deploy on the Moon’s surface. Engineers working on NASA’s Lunar Environment Monitoring Station, or LEMS, have completed hardware development and testing and the payload is ready for its permanent home near the lunar South Pole. With the hardware complete, LEMS is ready to support one of the Artemis program’s core goals: enabling sustained lunar science and exploration.
The LEMS instrument package contains two highly sensitive seismometers that will monitor ground vibrations from moonquakes and meteorite impacts, providing scientists with insights into the Moon’s interior and the seismic hazards astronauts might encounter at the surface. Its modular design allows the system to be adapted or expanded to host new instruments in the future, creating a reusable platform that can evolve as scientific priorities grow.
The payload will remain in a clean room at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, where it was built, until it is assigned to an Artemis mission for deployment to the lunar surface.
“The completion of the LEMS scientific instrument is a major step in a new era of lunar surface science. Innovative science experiments will uncover, measure, and reveal the Moon’s secrets while astronauts open new frontiers for discovery,” said Joel Kearns, deputy associate administrator for exploration, Science Mission Directorate, NASA Headquarters in Washington. “And, behind the scenes, countless teams across NASA and our partners are pushing the boundaries of what surface instruments can do, building the tools that will make future exploration possible and safer.”
A scientist wearing NASA’s xEMU prototype space suit is testing the handling of a mockup version of NASA’s Lunar Environment Monitoring Station, or LEMS. The testing took place at the Active Response Gravity Offload System, a simulated reduced gravity environment at NASA’s Johnson Space Center in Houston.
NASA Johnson
The LEMS payload builds on a legacy of lunar seismic tracking. Apollo astronauts deployed a network of seismometers on the Moon’s nearside equatorial region between 1969 and 1972. Those instruments operated until 1977, recording about 13,000 moonquakes and other ground vibrations that helped scientists begin to understand the composition of the Moon’s interior. For decades, researchers have hoped to spread more seismometers, updated with new technologies, across the lunar surface.
Now, LEMS will carry the first seismometers to be deployed by future astronauts to listen for faint ground vibrations, collecting new clues to the Moon’s internal structure and ongoing seismic activity. The sensors will be the most compact, sensitive, and energy-efficient seismometers ever built for planetary exploration.
LEMS itself is about the size of a small suitcase, weighing 11 pounds in the Moon’s low-gravity environment. It will carry not just these seismic sensors, but everything it needs to function independently of humans after deployment. LEMS is built to manage its own power production via a lightweight, flexible solar array that conforms to the shape of the LEMS unit. It also will manage its operational activities to ensure continuous data collection based on a preset plan, and monthly data transmission to Earth. The payload will do all this while maintaining a stable internal temperature throughout the massive day-to-night temperature swings of the South Pole region.
Mechanical Engineer Brie Ludwig inspects the Lunar Environment Monitoring Station (LEMS) in preparation for testing in a thermal vacuum chamber at Goddard Space Flight Center in Greenbelt, Maryland, on March 31, 2026. LEMS is a compact, autonomous, and self-sustaining seismometer suite designed to carry out continuous, long-term monitoring of the lunar seismic environment at the South Polar region.
NASA/Denny Henry
“When we conceived of LEMS, we weren’t just thinking about the next mission, we were thinking about the next generation of lunar exploration,” said Mehdi Benna, a University of Maryland Baltimore County scientist who leads LEMS from NASA Goddard. “Our vision was to create a scientific buoy for the Moon. Like an ocean buoy on Earth, LEMS is designed to be easy to build, adaptable to different scientific objectives, and capable of operating independently for years.”
Before any surface science could happen, Benna and his team had to ensure that LEMS could survive the trip to the Moon and the harsh environment of its surface. Over the past five months, LEMS and its components have been subjected to a demanding series of environmental and operational tests. Engineers verified LEMS can endure the violent shaking of launch, the journey to the lunar surface, and the Moon’s temperature and radiation environment. The team also showed that the instrument package’s mechanical and electrical design is safe for astronaut handling.
The LEMS payload was built to operate through the lunar night, which lasts two Earth weeks, without external power assistance or a heat source. Past lunar surface instruments relied on radioisotope heaters for warmth and power. But LEMS instead will withstand temperatures that dip to minus 400 degrees Fahrenheit in some areas by using advanced insulation materials, low-thermal-conductivity cables that minimize heat loss, and a thermal regulator that conducts heat away during the day to prevent overheating and helps retain heat at night.
These innovations reduce mass and power needs, setting the stage for lighter, energy-efficient instruments that can operate continuously at future Artemis landing sites and the NASA-led Moon Base.
The LEMS payload is led by University of Maryland Baltimore County and University of Maryland College Park. Technical implementation is led by NASA Goddard. The University of Arizona, in partnership with Silicon Audio, Inc., supplied LEMS’ two state-of-the-art seismometers. Morehead State University in Kentucky provided LEMS’ telecommunication system and will operate the instrument on the surface. Washington University in St. Louis will manage the instrument’s data processing and dissemination to the larger scientific community.