Question about periapsis in atmosphere

[ZachTM]

I just got this amazing game and got a tiny rocket into orbit. I didn't have enough fuel to get it out of this orbit to land back down, but I was able to get the periapsis of the orbit into the Kerbin atmosphere (48,000m right now). My question is since the rocket passes through the atmosphere will this take energy out of the orbit until eventually my rocket comes back down?

[Vanamonde]

Yes. At 48,000m, it might take more than one pass, but it will eventually de-orbit due to aerobraking. However, the affects of atmospheres are only applied if you are piloting that vessel yourself, or another vessel within 2.25km of it. In other words, it won't come down while you are operating other ships.

[ZachTM]

Thank you very much!

[Luis]

Which makes me wonder: could you build a refueling tanker and execute a rendezvous and docking to refuel it in the upper atmosphere before it deorbits? That would make an interesting video, if you could pull it off!

[larsmaehlum]

As you usually need at least one orbit to even get close to it, it's probably impossible. Might be possible to exploit the fact that it's on rails, but I'd say that is cheating.

[phuzz]

If your periapsis isn't quite low enough, but your AP is very high, then you can change your orbit using just a kerbal.

I found it was easiest to point my ship retrograde just before AP, so I had a nice target to push against (ie the engine nozzle), then Jeb did an EVA and pushed with his jet pack against the engine.

With an AP about half way out to the Mun, a 10s push from Jeb dropped my PE down by a few thousand meters.

A useful trick if you just need a few more m/s of dV to aerobrake.

[John FX]

If your periapsis isn't quite low enough, but your AP is very high, then you can change your orbit using just a kerbal.

I found it was easiest to point my ship retrograde just before AP, so I had a nice target to push against (ie the engine nozzle), then Jeb did an EVA and pushed with his jet pack against the engine.

With an AP about half way out to the Mun, a 10s push from Jeb dropped my PE down by a few thousand meters.

A useful trick if you just need a few more m/s of dV to aerobrake.

And in emergencies you can keep boarding and going back on EVA with a full jetpack.

[Jananton]

Yes. At 48,000m, it might take more than one pass, but it will eventually de-orbit due to aerobraking. However, the affects of atmospheres are only applied if you are piloting that vessel yourself, or another vessel within 2.25km of it. In other words, it won't come down while you are operating other ships.

Right, that explains why I have some pieces of debris circling where I thought of they would come down eventually, but somehow never do. ;-)

Thanks for clearing that mystery up.

Greets,

Jan