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  28. New Satellite Engine Could Use Earth's Atmosphere to Stay in Orbit Indefinitely (scitechdaily.com)
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New Satellite Engine Could Use Earth's Atmosphere to Stay in Orbit Indefinitely

48 pointsby 3h agoscitechdaily.com
9 comments
2h agoHN ↗

Very much not a new idea: https://en.wikipedia.org/wiki/Very_low_Earth_orbit

Though fun to see. More interesting than the station keeping (indefinite part) is that it enables ~100km orbits, which are ~5x closer than what remote sensing satellites use today and thus could get 5x the resolution for the same instrument.

2h agoHN ↗

Yes, the article also points out that the idea is not new, but rather that this research was focused on addressing practical problems, such as corrosion of the engine's parts.

1h agoHN ↗

Ideas require a ton of research to transform into reality.

43m agoHN ↗

~5x closer than what remote sensing satellites use today and thus could get 5x the resolution for the same instrument.

I would think a bit less. You won’t get a factor of 5 decrease in atmosphere to watch through and I would guess you’d get more vibration.

19m agoHN ↗

An Alcubierre drive is not a new idea either, but if someone demonstrated one I would be mightily impressed.

That is an extreme example for multiple reasons, of course, but the point is that the gulf between idea and working thing is often monstrous. Ideas are cheap, implementation is hard.

16m agoHN ↗

100km is the height where meteoroids ablate. You must mean 100k miles and even there the largest meteors start to become visible.

Indeed at the bottom tfb quotes heights of 190-250km for model calculations.

1h agoHN ↗

'contactless, neutralizer-less radio-frequency (RF) helicon plasma thruster'

fairly sure that wins just on the absolute impossibility of creating an acronym , just all business

works in wind tunnel testing.

9m agoHN ↗

The Earth's upper atmosphere is delicate. It's already being disturbed with rocket fuel residue and particulate space junk. Vacuuming up air and ionizing it risks putting the upper atmosphere even more out of balance.