Register for an account


Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.


Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.

The Sciences

Tomorrow’s Satellites Could Run on Air

D-briefBy Bill AndrewsMarch 8, 2018 2:16 AM


Sign up for our email newsletter for the latest science news

Air-breathing thrusters could power satellites of the future. (Credit: ESA) Breathe in. Breathe out. Take a second and just let the air flow naturally through you. When you’re having a tough time — you’re feeling an awful lot of resistance, maybe, or just running out of energy — remembering to breathe is important. It’s a mantra for a reason. And now it’s not just good advice for people. The European Space Agency announced this week they’d developed a satellite thruster that breathes too, solving a host of problems and establishing a possible new era for upper-atmosphere aircraft.


While it’s easy to think that space starts where our atmosphere stops, it’s actually not a very firm boundary. There is an “official” edge, but the atmosphere itself just tapers off, getting thinner and thinner. Satellites that orbit in that gray area have to compensate for air resistance, requiring extra fuel and entailing shorter lifetimes than missions farther away.


The air-breathing ion thruster. (Credit: ESA) The new thruster would bypass all that, “inhaling” the sparse particles of air up there and using them as propellant. Spacecraft equipped with the thruster could then fly very low orbits, around 124 miles up, for years on end.

Not Just Hot Air

The relatively simple machine — “no valves or complex parts” according to the ESA — basically sucks in the infrequent air particles and gases them up with heat and electricity. This lets the thruster shoot them out the back, providing a modest, but measurable, thrust (around 5 mph when all goes well). An Italian lab built and tested an actual prototype, running within a vacuum chamber to simulate the thin atmosphere, and saw that it really did work. New air-breathing propulsion systems may thus be the next big thing in spacecraft, opening a door into a new type of missions simply impossible with previous technology. And that isn’t limited to Earth, since Mars and other worlds have their own atmospheres that could power such machines. Whoa. Let me catch my breath.

    3 Free Articles Left

    Want it all? Get unlimited access when you subscribe.


    Already a subscriber? Register or Log In

    Want unlimited access?

    Subscribe today and save 70%


    Already a subscriber? Register or Log In