World-first firing of air-breathing electric thruster
In a world-first, an ESA-led team has built and fired an electric thruster to ingest scarce air molecules from the top of the atmosphere for propellant, opening the way to satellites flying in very low orbits for years on end.
[...] Replacing onboard propellant with atmospheric molecules would create a new class of satellites able to operate in very low orbits for long periods. Air-breathing electric thrusters could also be used at the outer fringes of atmospheres of other planets, drawing on the carbon dioxide of Mars, for instance.
"This project began with a novel design to scoop up air molecules as propellant from the top of Earth's atmosphere at around 200 km altitude with a typical speed of 7.8 km/s," explains ESA's Louis Walpot.
A complete thruster was developed for testing the concept by Sitael in Italy, which was performed in a vacuum chamber in their test facilities, simulating the environment at 200 km altitude.
(Score: 0) by Anonymous Coward on Wednesday March 07 2018, @11:21AM (6 children)
Will this allow ISS to stay in orbit, without frequent fuel resupplies?
(Score: 2) by beckett on Wednesday March 07 2018, @12:05PM
the mean height of ISS is just above 400km [heavens-above.com]; the project only tested at height of 200km, which was about as high as Sputnik-1 got.
(Score: 3, Informative) by c0lo on Wednesday March 07 2018, @12:39PM (4 children)
No, the air acts as a propelant, the spent energy is electric. You'll need to supply the electricity somehow.
If you think PV panels, there's a trade-off: the panels will create drag.
https://www.youtube.com/@ProfSteveKeen https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by fyngyrz on Wednesday March 07 2018, @01:30PM (1 child)
Even scooping up gas molecules adds drag.
However, integrated conformal PV panels can be designed on such that they don't add drag.
All of this is a balancing act. If the sum total of the thrust generated by gas molecules + impetus added by the electrical system is greater than the drag, and can be directed where it needs to go, the system can work.
(Score: 2) by c0lo on Wednesday March 07 2018, @02:18PM
This is why I said 'trade off' rather than 'outright impossible'.
https://www.youtube.com/@ProfSteveKeen https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by JoeMerchant on Wednesday March 07 2018, @01:45PM (1 child)
I was thinking of a new generation of satellites with hypersonic aero-design like a Blackbird... lay the PV panels along the body, might not be enough to keep it up (7-8km/s aerodrag has got to be a bitch to overcome...) but maybe with a nice hot plutonium pile onboard...
🌻🌻 [google.com]
(Score: 3, Informative) by richtopia on Wednesday March 07 2018, @06:52PM
The image from the article is similar to what you describe:
http://www.esa.int/spaceinimages/Images/2018/03/Air-breathing_space_mission [esa.int]