Orbit is decaying? Minmus.

[whiterafter]

I launched my new high-tech space probe to Minmus with a lot of new cool stuff on it like the Lazor System. Its at an extremely low altitude (Designed to clear ground by, eh, 25 m, at highest point). And its orbit is decaying. It's only going at like 5/6 m at a time, but every 3 orbits it randomly drops 5/6 meters in the periapsis. Considering I don't have much clearance, this is alarming.

As far as I know there isn't any orbital decay implemented in KSP yet... so, I'm messed up. It has no boosters/thrusters, and its carrier rocket (in hope of transferring fuel) is in a highly elliptical orbit.

But because this is a fancy shmancy state of the art satellite, I have a lot of data from it.

http://i.imgur.com/cnmfPdh.png

Thanks. Please contact me ASAP on what's going on. I don't want my satellite to die!

[whiterafter]

It wouldn't be hard to fix, but I really don't want to relaunch it.

[ShachonianX]

This is...... Odd

EDIT: NvM. I thought you meant Minmus's orbit was decaying. THAT would be odd.

Edited May 12, 2013 by ShachonianX

[maltesh]

When you're orbiting off-rails, your orbit is recalculated every timestep. Small differences in the position of your spacecraft's root pod as you go around the planet result in the observed differences of your periapsis and apoapsis altitudes.

When you're orbiting at 1x, or under physwarp, the projected orbit is a decent approximation of the course you're going to take, but your ship isn't stapled to that course unless you're orbiting at 5x or faster.

[gompasta]

Its probably just the structural wobble of the craft decaying your orbit. Now this wouldnt happen in real life, but in KSP, there is probably some phantom forces being applied due to number roundings.

[Stealth2668]

^ how do you know these things maltesh?

[Daze]

Like on reality there's orbital decaying in KSP but it only work during physical warp because when you time warp the orbit automatically goes on rails

[Procyon]

I seem to remember reading somewhere that low orbits have a tendency to be.. unstable? any truth?

[gompasta]

Like on reality there's orbital decaying in KSP but it only work during physical warp because when you time warp the orbit automatically goes on rails

Orbital decay is not modeled, as there is no... "Solar Atmosphere" (Cannot remember actual term) causing drag.

[Daze]

Orbital decay is not modeled, as there is no... "Solar Atmosphere" (Cannot remember actual term) causing drag.

I think the drag on a orbital decaying is caused by difference between gravity torce by passing on top of mountains or crater (Look for the reason why CM of Apollo Program orbit at that height)

Edited May 12, 2013 by Daze

[gompasta]

I think the drag on a orbital decaying is caused by difference between gravity torce by passing on top of mountains or crater (Look for the reason why CM of Apollo Program orbit at that height)

Gravity does not depend on the amount of mass underneath the object in KSP. It is only a defined constant central point.

[Daze]

Im not talking about the mass

""Solar drag"" should also make drag on planets in real life no?

[gompasta]

Im not talking about the mass

What you mean about the craters/mountains, are increased/decreased mass relative to the center of the body. Truthfully, that shouldnt really matter anyway.

""Solar drag"" should also make drag on planets in real life no?

No, as the drag is the particles outside of the planets atmosphere, either solar winds or random stray particles. The earths atmosphere is immensely denser than this, so it will probably not even be measurable, even if it was the case.

[Daze]

What you mean about the craters/mountains, are increased/decreased mass relative to the center of the body. Truthfully, that shouldnt really matter anyway.

No, as the drag is the particles outside of the planets atmosphere, either solar winds or random stray particles. The earths atmosphere is immensely denser than this, so it will probably not even be measurable, even if it was the case.

I'm talking on a little difference in gravitational force under mountain which can "curve" your orbit

For LEO and LKO (ISS need to be boosted some time at year) but on Mun and Minmus there's no atmosphere

[gompasta]

I'm talking on a little difference in gravitational force under mountain which can "curve" your orbit

For LEO and LKO (ISS need to be boosted some time at year) but on Mun and Minmus there's no atmosphere

I understand what you mean about the different gravitational forces. What I am saying is, that is not modeled in KSPs physics.

And there is small amounts of particles outside of a bodies atmosphere that can slow you down. However, the effects are tremendously minute.

[Daze]

And there is small amounts of particles outside of a bodies atmosphere that can slow you down. However, the effects are tremendously minute.

I approve on this but this works only on body with atmosphere, on Mun the orbital decay must came from the first thing i said no?

[gompasta]

I approve on this but this works only on body with atmosphere, on Mun the orbital decay must came from the first thing i said no?

Seeing as both of these things are not modeled, the orbital decay must come from what I mentioned earlier; Phantom forces coming from rounded off numbers, or weird physics calculations.

[Daze]

Seeing as both of these things are not modeled, the orbital decay must come from what I mentioned earlier; Phantom forces coming from rounded off numbers, or weird physics calculations.

The orbital decay happened to me also on probe 100% stopped without ASAS

[whiterafter]

Wait. It seems a lot of you are talking about time warp stuff.

So I should use another ship (in stable orbit) for timewarping it?

Or is my ship doomed and I should just take a bunch of pretty photos or crash it.

I noticed a comment on ASAS. I have "SAS" on, but I don't have the module, so its not really running.

What should I do?