Staying in orbit can be challenging, at least for lower orbits that are more affected by Earth's atmosphere. But, such orbits also come with advantages, such as better vantage points for new commercial operations such as Earth Observation and telecommunications connections. So there is an incentive for anyone who can figure out how to functionally keep a satellite in orbit at those lower altitudes for long periods. One of the best paths toward that goal seems to be an ion engine that takes in atmospheric particles and uses them for thrust. Now, a recently released paper explores potential use cases for such an engine and suggests a path toward their commercialization.

One of the biggest problems with maintaining very low Earth orbit (VLEO) is fuel. At those altitudes, usually considered below 450 km from the surface or about as high as the space station, the atmosphere drags on anything orbiting, which requires a consistent push from an engine to counteract.

When you test launch the most powerful rocket ever successfully flown, there's bound to be some collateral damage. With 8.8 million pounds of thrust at liftoff, NASA's Space Launch System (SLS) packs a mighty punch (the Saturn V, which carried astronauts to the moon in 1969, produced 7.5 million pounds). After November 16's test flight of SLS, dubbed Artemis I, the pad was a little worse for wear, but not outside of expected parameters, NASA officials say.

"The damage that we did see pertain to really just a couple areas on the 'Zero Deck,'" said Mike Sarafin, Artemis I's mission manager, at a press conference on November 21, referring to the section of the Mobile Launcher Platform that bears the brunt of the rocket engines at liftoff.