Orbit decaying while out of atmosphere?

[bloxgate]

I recently launched a SCANsat radar satellite into a inclined and fairly eccentric orbit. While watching it make progress on the scan I noticed the periapsis marker on SCANsat's map going down at around 0.1 m/s. Thinking this was just a glitch I exited the map I was looking at and checked MechJeb's orbit info, and much to my surprise my periapsis was actually going down. As I was at an altitude of at least 74 km at the time, and do not have any mods that add this sort of thing I am very confused. What's going on?

Solution:

Just timewarped. I don't recall any further issues once that flyby was done.

Edited October 11, 2014 by bloxgate
Added solution to origianl post.

[Heretic391]

Very unusual. Obviously this should not be happening as Kerbin has an atmosphere that extends to roughly 69,078 meters. You are clearly well above that. Make sure your engines are all completely off. Otherwise I have no idea what could be the problem. Maybe don't rely on MechJeb's orbit info as it could be incorrect. Idk I never use MechJeb. The game is easy enough. Good luck!

[LordFerret]

Touching the outer fringes of the atmosphere? I don't know how they calculate it, but I would think the boundary at 70km to be 'fuzzy'.

[CavemanNinja]

What planet are you scanning? this makes a difference.

[bloxgate]

Heretic391: My engines are completely off and disabled. The orbit map also shows this change so its not an error in MechJeb.

CavemanNinja: I am currently scanning Kerbin with the first scanner you unlock for SCANsat. I believe it is called the Radar Altimetry Scanner or something along those lines.

[cantab]

I saw similar behaviour once before. That time it was my Mun periapsis on a flyby that was steadily creeping down, regardless of the orientation of my ship, when I wasn't at timewarp.

[bloxgate]

What did you do to stop it, or did you just end up crashing into the Mun?

[cantab]

Just timewarped. I don't recall any further issues once that flyby was done.

[bloxgate]

Right, I'll try time warping up to apoapse and then increase my periapse a little. I'll let you guys know what happens.

[bloxgate]

Ok, so looks like the situation reversed itself after I changed my orbit at apoapsis. However the apoapsis then went up slightly and the change appears to have stopped! Thanks for you help everyone