A French company called ThrustMe announced recently tested a new type of iodine-based propellant for small satellites (Cubesats). The technology promises to extend the life of these satellites and even reduce the amount of space junk around the planet.
Cubesats are satellites composed of one or more cubic modules with 10 cm sides and a maximum of 1,3 kg each. They can be used for observation of the planet, for telecommunications (amateur radio, for example) and as a platform for testing ideas and projects that do not justify the cost or do not require a traditional satellite.
Due to their small size, they have no propulsion of their own. This means that it is impossible to correct an orbit error after a launch, or to change it so that they can accomplish a new mission.
In addition, the lack of thrusters means that at the end of their useful life Cubesats are condemned to wander through space for decades as space debris, something that could put other satellites at risk and even manned missions. Larger satellites, with propellers, can be directed to our planet and if disintegrate during re-entry into the atmosphere.
ThrustMe's system, called NPT30-I2, is simple, small and cheap enough to be used on a CubeSat. Iodine is non-toxic and solid at room temperature, but it sublimates (becomes a gas without going into a liquid state) when heated slowly.
In addition, it takes up less space than the fuel traditionally used in propellers, which is critical on a satellite where every millimeter of space is important. According to ThrustMe, an advantage of its product is that propulsion modules can be delivered “pre-filled” to its customers, simplifying their integration.
The technology was shipped on a commercial satellite called SpaceTy Beihangkongshi-1, launched in November 2020, and recently tested by ThrustMe on two 90-minute "burns" that resulted in a 700-meter altitude change.
The NPT30-I2 is already being offered commercially by ThrustMe, in the form of modules with 1U or 1.5U (1U being the size of a basic CubeSat with 10 cm on the side). Price was not informed.