[1.2] Real Solar System v12.0 Dec 8

[MattBox]

Does this work with the new asteroids? Can they be modelled in the space between Jupiter and Earth?

[SpacedInvader]

Does this work with the new asteroids? Can they be modelled in the space between Jupiter and Earth?

I think this has already been discussed before and the answer is maybe. My understanding is that the game generates these as ships and so its not possible to make them into a persistent belt, though it may be possible to force them to spawn in the belt. That being said, the other aspect of this is that, despite the number of asteroids in the belt, they are extremely spaced out, with several million kilometers between the largest, and even the smallest only presenting a minor chance of encounter. As such, if really modeled, you'd at most see 1-3 during a crossing of the belt and the fact that they can only really be randomly generated means you'd never be able to actually target one for interception as they won't be visible from Earth to set up an encounter properly.

This all being said, I think the real plan is to model some of the largest asteroids / dwarf planets (Vesta and Ceres) once we have a way to add planets through RSS.

[Spooks]

I have a probleem orbiting in the same orbital inclination any tips ?

[AndreyATGB]

I have a probleem orbiting in the same orbital inclination any tips ?

Line up your camera such that the orbit you want to get to is a single line. When your launch site crosses this line, launch. Assuming you're talking about a 28 degree inclination you can just burn east for both launches.

[dewinslow]

I haven't been able to find a definitive way to get kerbal engineer working... I understand that the delta v is partially correct, but my problem is TWR. Ships I build show a TWR of 1.5+ but sink to the launch pad. What am I doing wrong?

[NathanKell]

Use Padishar's latest dev build. In real life (and in RF) thrust is proportional to Isp. So at sea level, with a lower Isp, you get lower thrust.

[AndreyATGB]

I don't know about KER but MechJeb has SLT (Sea-Level Thrust) in addition to TWR.

[camlost]

Which one?

Also, they'll be included in the next release, if the repo is any indication.

There are four, Xichang, Jiuquan, Taiyuan and Wenchang

[SpacedInvader]

I haven't been able to find a definitive way to get kerbal engineer working... I understand that the delta v is partially correct, but my problem is TWR. Ships I build show a TWR of 1.5+ but sink to the launch pad. What am I doing wrong?

Max sure you're not looking at max TWR. Both MJ and KER show both starting and max TWR and if you're building a ship with max TWR at 1.5 I'm betting your starting is something like .5.

[SpacedInvader]

Here's a navigation question:

I'm getting ready to set up a comsat constellation for RT2 and would like to use an insertion method similar to this one, approximately how much delta-v would this require in my launch vehicle? My guess is it would be less than if I circularize at LEO and then extend outward, but the calculators I've been able to find always seem to want you to circularize first.

EDIT: Also has anyone ever tried using GMAT to work in RSS?

Edited May 22, 2014 by SpacedInvader

[Phredward]

Hi! I just noticed that RSS 6.1 has the whole solar system tilted 23 degrees to get the earth axis tilt. I'm excited / nervous to launch vehicles to other planets with this new change!

I also notice that other planets (Mars specifically) seems to also be tilted heavily, although real-life mars seems to only be tilted ~1.5 degrees. I assume that all planets & moons in KSP have to be at 0 degrees right now, but was just curious.

[NathanKell]

SpacedInvader: I haven't tried GMAT, but I don't see why it wouldn't work.

Regarding GTO, a transfer from 185x185 to GEO is 4.33km/sec (of which about 1.86km/s is the apogee kick and plane change combined, IIRC--it's 1.43km/sec just to circularize). So add that to whatever it takes to get to 185x185, which is somewhere between 9 and 10km/sec, depending on your launcher.

There is, in fact, absolutely no difference in dV cost between (1) circularizing at 185x185 and then raising apogee to geostationary height at AN/DN, and (2) combining the circularization and perigee kick (doing one big burn at DN): after all, in what's described in the article, at one instant during the burn the orbit will be 185x185, and then it will end up 35,786x185.

This is because you have to wait until the DN (or the AN, if you are launching from the southern hemisphere).

All this assumes, of course, that your LV's ascent is timed perfectly to hit (original) apogee at the DN/AN; if not, then circularize-first will be cheaper since you won't suffer higher steering or gravity losses.

If you were launching from an equatorial site, you might see some small savings from burning all the way to a 35,786km apogee when low and fast (taking maximum advantage of Oberth). But if not, you're constrained to beginning your Hohmann transfer at AN/DN.

Phredward: KSP does not actually support axial tilt. To fake it, we did as you see. That means, however, that only Earth's tilt is correct (i.e. the universe was reconfigured to give Earth its appropriate tilt). This is because in KSP all planets are aligned with the worldspace XYZ axes no matter their inclination; this is great for Earth (make its inclination equal to its real life tilt, yielding correct axial tilt) but bad for the other planets.

[scoops]

Hey I've been having issues with RSS. I'm running just RSS and I can't see the KSC switcher button. I'm using the older build (0.23.5 still doe) I don't think that would make a difference though.

[SpacedInvader]

SpacedInvader: I haven't tried GMAT, but I don't see why it wouldn't work.

Regarding GTO, a transfer from 185x185 to GEO is 4.33km/sec (of which about 1.86km/s is the apogee kick and plane change combined, IIRC--it's 1.43km/sec just to circularize). So add that to whatever it takes to get to 185x185, which is somewhere between 9 and 10km/sec, depending on your launcher.

There is, in fact, absolutely no difference in dV cost between (1) circularizing at 185x185 and then raising apogee to geostationary height at AN/DN, and (2) combining the circularization and perigee kick (doing one big burn at DN): after all, in what's described in the article, at one instant during the burn the orbit will be 185x185, and then it will end up 35,786x185.

This is because you have to wait until the DN (or the AN, if you are launching from the southern hemisphere).

All this assumes, of course, that your LV's ascent is timed perfectly to hit (original) apogee at the DN/AN; if not, then circularize-first will be cheaper since you won't suffer higher steering or gravity losses.

If you were launching from an equatorial site, you might see some small savings from burning all the way to a 35,786km apogee when low and fast (taking maximum advantage of Oberth). But if not, you're constrained to beginning your Hohmann transfer at AN/DN.

Phredward: KSP does not actually support axial tilt. To fake it, we did as you see. That means, however, that only Earth's tilt is correct (i.e. the universe was reconfigured to give Earth its appropriate tilt). This is because in KSP all planets are aligned with the worldspace XYZ axes no matter their inclination; this is great for Earth (make its inclination equal to its real life tilt, yielding correct axial tilt) but bad for the other planets.

Ok, so it seems that perhaps the reason they've chosen this method is because they're much closer to the Equator, and also because it might allow for a somewhat simpler launch profile since you just keep burning until your transfer apogee is at geostationary height. I get from your explanation that it's unlikely that this method would offer much benefit over launching to a circular orbit and then kicking out, though, with that being said, the reason I originally landed on this method is because this will be the first satellite in my RT2 constellation, so there would be a benefit in my specific case as it will save me from having to wait in orbit for my AN/DN to occur over a ground station. With that in mind, the next question I have is how much less efficient would it be for me to launch with a much steeper ascent angle, essentially staying sub-orbital and skipping the circularization burn until I reach apogee at GEO height, or would it even be possible to do this and have the apogee be near the equator?

Edited May 23, 2014 by SpacedInvader

[Phredward]

Phredward: KSP does not actually support axial tilt. To fake it, we did as you see. That means, however, that only Earth's tilt is correct (i.e. the universe was reconfigured to give Earth its appropriate tilt). This is because in KSP all planets are aligned with the worldspace XYZ axes no matter their inclination; this is great for Earth (make its inclination equal to its real life tilt, yielding correct axial tilt) but bad for the other planets.

Yeah, that's what I suspected. Here's hoping they add that as a feature in the future!

[NathanKell]

SpacedInvader: No, unless you time your ascent such that you reach apogee (and begin your perigee kick to place your apogee at geostationary height) exactly as you pass the equator, and are under thrust all the time, you can't do it in one burn. (Well, you can, you'll just have to make a separate plane change after you circularize in GSO, which is wasteful.)

Due to orbital mechanics, unless you inject into GTO at the AN or DN, you will not have your apogee at the same location as the DN/AN (respectively), and therefore will not be able to combine apogee kick (to circularize at 35,786km) and plane change (to lower inclination to 0).

The reason to circularize first is because it's much easier to launch into a parking orbit and then raise apogee than it is to time your ascent such that ascent apogee is placed over the equator.

Besides it being more expensive, the method you propose (burning straight up) is actually more dangerous: odds are KSC will no longer be "under" you when you reach apogee, and since you won't have raised your perigee enough to establish an orbit, you'll just fall back to Earth and burn up.

By contrast, if you launch into a parking orbit, you can time your GTO injection burn such that KSC will be under you (you'll be in communication). Then, you stay in that orbit (since it's 35,786x185, it's a stable orbit) until KSC is under you at apogee (it will take quite a few passes, probably), at which point you perform apogee kick.

[SpacedInvader]

SpacedInvader: No, unless you time your ascent such that you reach apogee (and begin your perigee kick to place your apogee at geostationary height) exactly as you pass the equator, and are under thrust all the time, you can't do it in one burn. (Well, you can, you'll just have to make a separate plane change after you circularize in GSO, which is wasteful.)

Due to orbital mechanics, unless you inject into GTO at the AN or DN, you will not have your apogee at the same location as the DN/AN (respectively), and therefore will not be able to combine apogee kick (to circularize at 35,786km) and plane change (to lower inclination to 0).

The reason to circularize first is because it's much easier to launch into a parking orbit and then raise apogee than it is to time your ascent such that ascent apogee is placed over the equator.

Besides it being more expensive, the method you propose (burning straight up) is actually more dangerous: odds are KSC will no longer be "under" you when you reach apogee, and since you won't have raised your perigee enough to establish an orbit, you'll just fall back to Earth and burn up.

By contrast, if you launch into a parking orbit, you can time your GTO injection burn such that KSC will be under you (you'll be in communication). Then, you stay in that orbit (since it's 35,786x185, it's a stable orbit) until KSC is under you at apogee (it will take quite a few passes, probably), at which point you perform apogee kick.

I'm actually working with the RT2 config that has all of the new launch sites as ground stations, so surface coverage is a little easier to work with, though there are quite a few large gaps that make launching from the cape somewhat tricky without additional coverage (hence the planned constellation). That being said, I see how it would be way more difficult to get the apogee in the right place with a single burn, so parking orbit it will be.

[jsimmons]

Updated the RealSolarSystem.cfg for 10x kerbol system. Thanks goes to starstrider42 for pointing out the sqrt(10) factor for the rotational periods of planets and moons to preserve the synchronous rotation

and escape velocity behaviors. In the stock game Ike is always in the same position in the sky from the surface of Duna. My original configuration file broke that. With the sqrt(10) scale factor it now behaves correctly.

With the new numbers a kerbal day is now about 19 earth hours which is much more reasonable. Also the new geostationary orbit is now 28,687,579m.

Edited May 24, 2014 by jsimmons
link cleanup

[ThePinda]

I have installed RSS with the Planet Factory config, and Venus/Eve is still purple. The atmosphere hue is purple, and the surface is purple. The heights are all correct, the surface is just the wrong color. Anyone know what I'm doing wrong?

[AndreyATGB]

Nothing, nobody has edited the PQS for Eve to change its color. You can get a fake Venus with EVE clouds, but from the surface it'll still be purple.

[NathanKell]

jsimmons: cool!

[Nicholander]

Has anyone made a thing for this where you can change KSC toBaikonur Cosmodrome, and if it has been done can someone give me a link to it?

[SpacedInvader]

Ok, so here's the question of the day. I had originally thought the maps I had for the moons of Jupiter were going to be pretty decent already, only to find out that what I thought were fairly minor areas of blurring are pretty obvious in game. I'm currently (and slowly) working on manually touching up the images to get rid of the blurry areas, but I'd expect that process to take somewhere between 2 and 4 weeks based on my current schedule. The question I have for all of you is this, based on the following gallery, would you rather have them now with all their blurriness, or are the current KSP moons a good enough stand in for the next few weeks and you'd rather have them when they are done?

Javascript is disabled. View full album

Thoughts?

EDIT: Note, only Io and Europa have normal maps in this, and they are both pretty quick and dirty, which would not be true of the release.

Edited May 25, 2014 by SpacedInvader

[SpacedInvader]

Has anyone made a thing for this where you can change KSC toBaikonur Cosmodrome, and if it has been done can someone give me a link to it?

Watch for this in the next update.

[regex]

Watch for this in the next update.

Actually it's already in there and working, and for quite some time you could have always defined KSC as being at Baikonur's location, but the launch site switching feature is missing launch sites for RSS proper until the next version. So it's really up to whether you want to do the work to make it happen now or just wait for the update.