Smallest orbit

[AeroPelican]

The challenge is to have the lowest apoapsis possible and do a full orbit around Kerbin, without mechjeb or instant orbit. You must have a pic of takeoff you at apoapsis, you at periapsis and you back at apoapsis. The last three pics must have your apoapsis shown. Good luck! ;D

[G Addict]

Does it have to be a non-decaying orbit? Because if so, the smallest possible orbit is 70kmx70km. Making people work out how far into the atmosphere they can get away with could be interesting, though.

[maltesh]

The challenge is to have the lowest apoapsis possible and do a full orbit, without mechjeb or instant orbit. You must have a pic of takeoff youat apoapsis, you at periapsis and you back at apoapsis. The last three pics must have your apoapsis shown. Good luck! ;D

Hmm. Challenge accepted.

Apoapsis altitude: 6,074m.

Apoapsis radius: 66,074m.

Periapsis altitude: 5,967m.

Semimajor Axis: 66,021m.

[Cthulufaic]

I think he means In orbit around Kerbin

Theres already a thread somewhere for the lowest possible Mun orbit without hitting anything.

[Bluejayek]

Does it have to be a non-decaying orbit? Because if so, the smallest possible orbit is 70kmx70km. Making people work out how far into the atmosphere they can get away with could be interesting, though.

AFAIk its acually 69201/69201. But if you try to cut it that tight the kraken will probably reel you in.

[SunJumper]

In terms of decaying orbits and .cfg edits, I\'ve managed a 2km by 2km orbit.

[AeroPelican]

Just to make it clear, the thing about the mun was a joke, and you must do a full orbit so it must be non decaying.

[SunJumper]

You know, I edited a part with a drag of 20. It begins to slow at 65km....

[Bluejayek]

Just to make it clear, the thing about the mun was a joke, and you must do a full orbit so it must be non decaying.

The point is, this is a nonsense challenge. The minimum stable orbit is hardcoded in at 69200m where the atmosphere begins. Its not a \'challenge\' to try to get an orbit here when you know the altitude, other then trying to fight the kraken for those last few meters.

[closette]

Well I suppose there might be a smallest orbit where you make it once around Kerbin before the orbit decays, by having a large apoapsis outside the atmosphere to start with. Sort of a minimal aerobraking challenge.

Unfortunately I'm seeing a lot of newer challenges that could do with following some informal guidelines that many of us have been using for a while, namely:

- Define 'success' in terms of measurable criteria[/li]

- Define the evidence ('proof') required unambiguously [/li]

- Maintain an updated 'leader board' in the first post [/li]

= Probably most important of all, at least try the challenge yourself first and post your own results and evidence. That usually shakes out any problems, including whether or not the challenge makes sense, or is even possible. [/li]

I wish I could add these guidelines (not rules!) to the sticky post at the head of the Challenges forum but replies to it are disabled.

Edited August 4, 2012 by closette

[AeroPelican]

Well, I cannot try it myself because I am on holiday...

[A Fat Pokemon]

I had debris that was orbiting Kerbin at 40,000m. It apears it was not affected by atmosphere, but this was back in .15

Edited August 5, 2012 by A Fat Pokemon

[Maizah]

you know, you could 'orbit' in the atmosphere if you build a sufficient spaceplane....

enough lift, and you could sustain an orbit within the hardcoded limit.

[maltesh]

I had debris that was orbiting Kerbin at 40,000m. It apears it was not affacted by atmosphere, but this was back in .15

I think stuff on rails will happily orbit at any altitude higher than ~21km over Kerbin. Perhaps I\'ll try editing an atmospheric Impossisat into a 25-30 km Kerbin orbit.

[Bluejayek]

you know, you could 'orbit' in the atmosphere if you build a sufficient spaceplane....

enough lift, and you could sustain an orbit within the hardcoded limit.

Only through the infiglide glitch. In reality, drag would slow you down just as it does anything.

[PLB]

From experimentation, 75 km is where there is the least drag is there, but you are still in the atmosphere, so I suggest for an AP of 80.

[Thobewill10]

The atmosphere cuts off sharply at ~69201 km.

[closette]

@PLB: Not sure where you get that from. 70 km is outside Kerbin\'s atmosphere so the drag is non-existent there, not 'least'.

Try this experiment: establish a 72x72km orbit (or close thereto), then gradually retrofire at apoapsis to bring periapsis down to, say, 68km. Time-warp and note the altitude that you are thrown back into 1x speed. That\'s where Kerbin\'s atmosphere 'ends'.

[UmbralRaptor]

It works, but you\'ll want to drop the orbit fairly slowly (and keep eccentricity down) to get high precision.

[closette]

I just did this and verified a pre-0.16 result reported here: http://kerbalspaceprogram.com/forum/index.php?topic=5623.msg92331#msg92331

that the atmosphere ends at 69077.5 m above sea level. Screenshot attached to show x5 warp is possible below 69200 m. (I didn\'t hit F1 fast enough to catch it right after 69077.5 m, but you can try for yourself).

[AeroPelican]

Good but you need more pics to qualify.

[closette]

I wasn\'t trying the (rather pointless as described) challenge - I was just verifying that the edge of the atmosphere is where it has been since before version 0.16. Time to move on...

[AeroPelican]

Well if you are not bothered doing the challenge then don\'t post anything here, and I don\'t understand why you don\'t understand the challenge.

[A Fat Pokemon]

Well if you are not bothered doing the challenge then don\'t post anything here, and I don\'t understand why you don\'t understand the challenge.

Im pretty sure he is allowed to post in any topic, save its not locked. It is actually benificial to the challenge, as he was stating the point at which the atmosphere cuts off, so it will help people in your challenge =/

One thing though, im wondering, is if the cockpit has to be under that cutoff point for it to experience drag from the atmosphere, or if any part can be in the atmosphere thats apart of a craft and experience drag. As I noticed, it does not affect debris within the atmosphere, this could be an interesting thing to find out while attempting this challenge surely.

[cardgame]

I was hoping some people would actually try for a rocket (not spaceplane) orbit in-atmo. During a horrifyingly miscalculated rocket test, I dipped down to approximately 30km before burning up and away. Sucked up almost all of my fuel but flying along at 3400m/s at 30km is pretty beastly.