Silicon Valley startup Momentus will present their Water Plasma Engine at Y-Combinators “Demonstration Day” from August 20-22nd after which they will announce plans to attract investment, including the launch of a kickstarter. They’ve also signed a contract with ECM Space, a European launch company that will provide their first trip to space for testing propulsion systems on a micro-satellite. That primary launch is set for 2019.
Like Ad Astras Vasimir Engine the company plans to encapsulate a market available to anyone that can build engines that are more efficient and less expensive then todays chemical rockets or Xenon based plasma thrusters.
Mikhail Kokorich, founder of Momentus made his fortune in years following the soviet union. He’s got a lot of experience in the space industry, previously founding a Russian small satellite company called “Dauria Aerospace”.
His new company wants to make Lunar travel and beyond more realistic by decreasing the cost of propellant. Their final goal is to help create an economy that incentivizes space colonization by erecting an infrastructure for transportation based on cheaper propulsion technology.
“When transportation costs decrease, many business models emerge” Kokorich says.
Through using water to power spacecraft beyond Low Earth Orbit you can reduce the cost of launching kilograms of chemical propellant from ground level. For one – water is lighter then chemical propellant, so it can be launched from Earth more easily and two – it is more abundant in space.
This is the reason behind recent experiments involving solar powered hydrolysis of water under zero gravity conditions – that is the splitting of water in to hydrogen and oxygen for fueling combustion based chemical engines. However as we are learning, under certain circumstances, it is best that chemical propulsion is simply done away with entirely.
“If you move something with a chemical booster stage to the moon. Chemical propulsion is good when you need to have a very high thrust,” according to Kokorich. Once a ship gets beyond gravity’s pull, water simply works better, he says.
It is also why several asteroid mining corporations (1)(2) plan to mine water ice before they even take a shot at precious metals. The bottom line is that using water whether it be for chemical or plasma based propulsion simply makes much more sense in the long run. In fact mining water ice was a vital topic at the most recent assembly of nations, companies and scientific organizations who have began discussing the practical implications of mining our moon.
The difference between Momentus water plasma engine and conventional hydrolysis however is that the Momentus engine ionizes water creating a super hot energized water plasma that can power the craft instead of chemicals like Hydrogen and Oxygen. That is a good idea for a couple reasons.
Number one is that it reduces unnecessary steps like splitting water up, separating the hydrogen from oxygen and redirecting them to separate compartments for storage. With Momentus propulsion tech, all you have to do is put water in the engine.
Number two: because of this, any water that is mined from either the Moon or Near-Earth Asteroids could be more quickly utilized for the propulsion of necessary craft. That would especially be the case if Transastras in citu ice water melting strategy were deployed in combination with the Momentus’ engine.
Not only is water plasma based propulsion better then hydrolysis and chemical propulsion, it is also better then current Xenon based plasma thrusters.
“When ionized propulsion is used for geostationary satellites to orbit, it takes months,” says Kokorich, using water can half the time.
“We can carry ten tons to geostationary orbit and it’s much faster,” says Kokorich.
The company wants to eventually power water prospecting and delivery throughout the solar system, solar powered stations, in-space manufacturing and space tourism.
Momentus has explained their engines in the following way
“We use solar energy to heat water with microwaves up to the sun’s surface temperature and eject the superheated gas through the nozzle to create thrust. One of the main problems we solved is how to make sure that plasma will not vaporize the chamber walls and nozzle.”
However, Ad Astra accomplished this task before them utilizing a spinning vorticular magnetic field to keep hot plasma from touching the inner walls.
Where they claim their singular VASIMIR engine can cut transportation costs by an entire order of magnitude Momentus has designed several engines for different tasks
They plan to demonstrate “Vigor” their first water plasma thruster by February 2019.
It will fly aboard a 16-unit cubesat launched from a Russian Soyuz rocket.
In 2020, Momentus will demonstrate their Ardoride propulsion system meant to power spacecraft weighing between 500 and 1,000-kilograms.
Perhaps Momentus will play a key role in the development and maintenance of the Lunar Orbital Platform-Gateway, the International Moon Village, Asgardias Space Stations, or Space-X’ Mars colony through the provision of inexpensive propulsion technology. However, they are going to begin by servicing orbital satellites in a competitive futuristic environment spotted with asteroid mining corporations, moon bases and new international space stations.
Other water based engines:
Deep Space Industries sells Comet, a water-based small satellite propulsion system.
Tethers Unlimited offers Hydros, a water electrolysis thruster.
Aerospace Corp built water-fueled thrusters for the NASA Ames Research Center’s Optical Communications and Sensor Demonstration mission launched in November 2017.