Noob question: When does a craft become debris?

[m4nti]

Hey all, I'm a new guy to Kerbal and I've spent a couple hours messing around with the game and trying to get a small satellite into orbit.

So yesterday, I put up a small Stayputnik satellite into orbit. It had a few sensors on it for fun, an antenna and a few solar panels. I decoupled the final fuel tank and I was done.

But when I tried to return to the space station (through the menu) the button was disabled. I had to "End Flight" instead.

Why? My satellite was now marked as debris and I couldn't go to it to see the readings/check out the kerbin view.

Am I missing something? I'd like to fix this before I move on to bigger challenges.

Thank you all for your time.

[Xiphos]

Hi and welcome! A ship will become debris when it is not connected to a command pod. Etiher manned or unmanned. If manned, put a kerbal inside(ie: hitchhicker storage) and the part will remain active. So just make sure your satellite has power and has an unmanned pod built in. Good luck!