Startup thinks it can make rocket fuel from water. Stop laughing

General Galactic, co-founded by a former SpaceX engineer, will test its water-based thruster this fall. If successful, it could help usher in a new era of space travel. But it’s a big “if”: sometimes it takes more than a “space burp.”

The idea of ​​transforming water in fuel for rockets has existed since the Apollo program era, and has been promoted in recent years by the likes of former NASA administrator Bill Nelson and the CEO of SpaceX, Elon Musk.

But here’s the thing: no one has ever done it successfully, at least not for a spacecraft of significant size.

led by a pair of engineers in their twenties, aims to be the first to do so. This fall, the startup plans to launch a 500-kilogram satellite, using water as the only propellant in orbit.

“Everyone wants to build a moon base or a base on Mars or whatever. Who is going to pay for this? How does this really work?” he asks Halen MattisonCEO da General Galactic.

“Our vision is build a gas station on Mars“, he adds, “but also, along the way, develop the refueling network“.

That’s the plan for the very, very long term, at least. To begin with, Mattison, a former SpaceX engineerand its CTO, Luke Neisea Varda Space veteran, has purchased a seat on a Falcon 9 rocket launch. Liftoff is scheduled for October or later in the fall.

There are, to simplify things a lot, two main types of engines that can be used on a spacecraft, explains the magazine.

You can take a fuel like liquid methaneperhaps combine it with an oxidizer, and burn it. It’s called chemical propulsionand every big rocket you’ve ever seen take off uses some variation of this method, because it provides a lot of thrust, even if it’s not terribly efficient.

Or you can take a gas like xenonapply electricity to it and expel it from the spacecraft, either as ionized gas or plasma. It’s called electric propulsion — again, oversimplifying.

Electric propulsionhas very, very low thrust. People like to jokingly call him a burp in spaceo,” says Mattison. “But it lasts forever. The efficiency is incredible.”

Sufficient “burps” over time can be quite effective. Electric propulsion is used to keep satellites in the proper orbit and to power space probes like Dawn, which NASA sent to explore the asteroid belt.

Water is not ideal for either electrical or chemical propulsion. But it can be good enough for both. Unlike liquid methane, for example, we don’t need to worry about the water accidentally make it explode the spacecraft, either keeping it cooled to -160 degrees Celsius, or having it evaporate when the satellite faces the Sun.

General Galactic now plans demonstrate both methods during your mission.

For chemical propulsion, it will use electrolysis to split water into hydrogen and oxygen, then it will burn the hydrogen, with oxygen as the oxidant.

For the electric propulsion system, the so-called “” will split the water and then apply enough electrical energy so that the oxygen becomes plasma. From there, use a magnetic field to shape the plasma and expel it.

“The idea is to show that we can provide both long-term maneuver efficiency and sometimes people need to get somewhere quickly or respond very quickly to a dramatic event in the orbital environment,” says Luke Niese. “Sometimes it takes more than a burp in space“.

For example, Chinese and Russian satellites have been flying increasingly in close proximity to American satellites. Find a method to maneuver and move away quickly from rivals is something the US Space Force and others are extremely interested in.

The hope, says Mattison, is that “we can give five or ten times the Delta-V of the mission”, using the jargon for the total change of speed and direction what a spacecraft can do over time.

There are reasons why this has never been done. THE ionized oxygen interacts with everythingpotentially corroding the electric propulsion system. “It’s not an easy element to work with,” he says Ryan Conversanoa former Jet Propulsion Laboratory technologist who is serving as a consultant for General Galactic. “It makes the selection of materials and the design of the device or devices very, very challenging“.

As for the chemical propulsion system, it is not clear whether General Galactic’s will be sufficiently competitive with more traditionalonce the extra mass of the electrolysis system has been added.

“It could be a very, very clever way of providing thrust to a small satellite,” he says. Mark LewisCEO of the Purdue Institute for Applied Research and former chief scientist of the U.S. Air Force. “But there are many ses“.

Lewis believes that It’s definitely worth a try, though.. If General Galactic can meet or exceed its expectations for this introductory effort, it could begin to be an answer to many of the problems at the heart of tomorrow’s missions to the Moon and beyond.