KSP-ified Accurate ISS

[stickman939]

Hey guys, I'm trying to make a stock version of the ISS and I'm trying to get it as accurate as possible.

But I can't figure out how to get the orbital period (in-game) to equal the real ISS.

I know that the ISS is a in LEO (Low Earth Orbit) and that it circumnavigates(?) the earth 16 times in 24 hours (90min/24h)

I feel like this should be simple, lol xD

[Yellowburn10]

Well, if you want the in-game orbital period to equal the real one, a Kerbin day is about 6 hours long. I don't know the specifications, but an orbit that circumnavigates Kerbin 16 times every 6 hours should be feasible enough.

[stickman939]

That helps. Thanks

[MalfunctionM1Ke]

your orbital period differes with your altitude. Sadly to say that i am lacking the math to figure out what your period would be in a 100km Orbit around kerbin :/

But my Point is that i would rather keep my station in a similar Orbit height than period.

BTW. let me share this link for figuring out where the ISS is right now.

http://www.esa.int/Our_Activities/Human_Spaceflight/International_Space_Station/Where_is_the_International_Space_Station

Edited May 28, 2015 by MalfunctionM1Ke

[Grumman]

I don't believe it is possible to orbit Kerbin 16 times per day without being inside the atmosphere - by my calculations, the minimum orbital period is 30 minutes, 34 seconds.

At 100 kilometers, it should be 32 minutes, 38 seconds.

The formula for any orbit around Kerbin should be: T = sqrt(0.0111786*(600+height)^3) where the height is in kilometers above sea level.

Edited May 28, 2015 by Grumman

[Rhomphaia]

To orbit 16 times in a Kerbin day would not only be inside the atmosphere, it would need a tunnel.

Even trying to keep the same ratio of altitude to planetary radius would mean orbiting inside the atmosphere.

[Streetwind]

Which isn't entirely unrealistic because the real ISS also orbits "within the atmosphere" by some definitions It needs constant reboosts to keep it from falling out of the sky due to atmospheric drag.

The basic issue here is that a Kerbin day is so short. You could perhaps halve your desired number of orbits per day from 16 to 8, that might help.

[Grumman]

The basic issue here is that a Kerbin day is so short. You could perhaps halve your desired number of orbits per day from 16 to 8, that might help.

That would give an altitude of 252 kilometers, by the way.

[Motokid600]

See Bob Fitch's project gateway for design inspiration. Dude made a beautiful ISS replica in his series.

[Dman979]

What I would do is to recreate the orbit to scale. Since the ISS has a ~250 Km orbit, multiply that by .64 to get your altitude. There's nothing you can do about the surface passes, you can't slow kerbin down.

[SkyRender]

What I would do is to recreate the orbit to scale. Since the ISS has a ~250 Km orbit, multiply that by .64 to get your altitude. There's nothing you can do about the surface passes, you can't slow kerbin down.

Uhhh, the ISS has an orbit of 409km/416km, roughly... Scaling that down for Kerbin would have you "orbiting" inside the atmosphere by quite a margin.

[Dman979]

Oh, I didn't know that. But the method still works.

[Slam_Jones]

If you're not opposed to mods, the Realism Overhaul suite scales up the whole Kerbol system to real-world scale, including planet size and distance between them.

If you want a truly accurate replica, you might consider trying it out

[Temeter]

Uhhh, the ISS has an orbit of 409km/416km, roughly... Scaling that down for Kerbin would have you "orbiting" inside the atmosphere by quite a margin.

That would be a 260km orbit, not sure how you'd expect to touch the atmosphere from up there.

[Mr Shifty]

That would be a 260km orbit, not sure how you'd expect to touch the atmosphere from up there.

.64 is the scale factor for Kerbal/Human. For Kerbin/Earth, the scale factor is about 0.09

[stickman939]

You learn new things ever day! lol. New numbers for scaling!

That'll be very helpful. I've settled with about a 250km orbit in the end. I figure that's a good stop between Kerbin and the Mun (and beyond).

HOWEVER:

It's very interesting to see how others would accomplish this!

Such a great community.

[TrooperCooper]

I think someone needs to install the Real Solar System mod.

[KerikBalm]

.64 is the scale factor for Kerbal/Human. For Kerbin/Earth, the scale factor is about 0.09

That depends if you are talking about the planet diameter, or atmosphere thickness/scale height.

Kerbin's atmosphere is much thicker relative to its diameter than Earth's.