NASA and Aerojet Rocketdyne have successfully tested early systems integration for their fuel efficient “Hall Thruster”. This new propulsion system could help humanity get back to the Moon and journey forth to the red planet
The main distinguishing characteristic of a Hall Thruster is the Ion propulsion engine, whereby free flowing, solar powered electrons are shot in to a tank of xenon gas, displacing local electrons from the gas atom and transforming them in to a soup of “ions”
Ions are basically just ordinary elements that have lost or gained an electron. They begin to “leak” electromagnetic energy as a result, and that energy can be used to propel a craft forward.
Once the Xenon atoms are sufficiently ionized millions of them are shot out of the exhaust to produce thrust. The best part of a Hall Thruster is that their are no violent eruptions to control for. Thermodynamic pressure is negligible compared to contemporary chemical combustion engines.
Testing conducted at NASAs Glenn Research Center proved the engine converts power efficiently, while at the same time producing minimal waste heat. In other words, the Hall Thruster has “decreased entropy” compared to other engines.
Energy efficiency is the main benefit here. Being roughly 10 times more efficient then combustion engines, one can easily see why NASA is so interested. However, the trade off is relatively low thrust compared to combustion.
With that being said, the Hall Thruster is still one step above older electric propulsion engines currently employed by NASA – possessing roughly twice as much thrust. So even know the technology doesn’t replace combustion engines entirely – they will still find use in longer journeys such as to the Moon or even Mars.
Aerojet Rocketdyne is currently working on a 13-killoweat Hall Thruster string for NASA. However, a prototype is already deployed in orbit for maneuvering satellites.
‘By staying on the cutting edge of propulsion technology, we have positioned ourselves for a major role not only in getting back to the Moon, but also in any future initiative to send people to Mars,’ said Eileen Drake, Aerojet Rocketdyne CEO and president.
Other ground breaking engines include those that work with similar principles such as plasma thrusters. One could argue that plasma and ion are actually being used interchangeably in both cases.
Ad Astras VASIMIR engine is characterized by dynamic variable impulse which make it a good all around “swiss army knife”. Whereas Momentus symbolizes a step toward a more pragmatic fuel source. In this case – water that can be ionized in to water plasma, and shot out of the engine much in the same way as the Hall Thruster.
Except that water can be mined from asteroids, a big distinction that will make it stand out from the rest as our new outer space economy begins to open up to commercial asteroid mining