The Japan Aerospace Exploration Agency (JAXA) announced in a press release on November 26 that it successfully used a water propellent system to drive its "EQUULEUS" CubeSat. The craft was launched by NASA's Artemis I on November 16.

EQUULEUS has a water propellant engine named AQUARIUS (AQUA ResIstojet propUlsion System) that uses heat from communications equipment to turn water into steam, which can be jetted out to generate thrust.

Why Use Water as Fuel?

Water is a better choice than other fuels for use in small, cheap satellites because it is easier to store and handle.

EQUULEUS Flight Path

Artemis I injected the spacecraft into a lunar flyby trajectory. Then EQUULEUS fired its steam engines and started its journey to the second Moon Lagrange point (EML2), and it should take a year and a half to reach EML2.

"I am proud of the EQUULEUS operation team, who were able to immediately complete the orbital control necessary for the lunar fly-by, just one day after the checkout operation shortly after launch. This was a difficult operation that had to be successful. I feel we were able to succeed in this critical operation due to their careful preparation, including numerous back-up plans, and the ability to respond flexibly through training. We are now at the start line of the long voyage to the Lagrange point," said FUNASE Ryu, an associate professor at the Department of Aeronautics and Astronautics, the University of Tokyo, Japan.

If you want to know more about EQUULEUS and how it works, read Development of the Water Resistojet Propulsion System for Deep Space Exploration by the CubeSat: EQUULEUS.

A security flaw in networking technology used in spacecraft, airplanes, energy generation systems, and industrial control systems has been discovered by researchers from the University of Michigan, the University of Pennsylvania, and NASA.

If you want to know more about PCspooF, read PCspooF: Compromising the Safety of Time-Triggered Ethernet.