A Kerbal's Guide to our solar system

[Cepheus]

Sorry to be a bother, Nova, but do you still have those Large, poster-sized images? I\'d really love to see \'em again. Found em.

Also, I\'m working on filling in some of the finer details of these guys. I\'d like to add them to the wiki. If you\'ve abandoned this, I would also like to finish it up.

[Spearka]

not much is happening here is there?

[NovaSilisko]

not much is happening here is there?

I got back into part making mode, rather than 'pretend to be a game developer' mode. I determined the former was much more useful to everyone.

[jake118533]

I cant wait to go to Eve! i rlly want to land on one of its moons and set up a base. And it seems that it will be hard to get 3 new plantes in between kerbin and the sun or wutwever its called 8)

[Spearka]

come to think of it, Nova originally said about of another planet beyond Kerbin from Kerbol named 'Meander' with has Egar as its moon, we have yet to see it on the map

[TheDeparted]

Kerbin

Kerbin is our home, and the birthplace of Kerbalkind. The only planet known to support life, it has produced a diverse civilization of accident-prone green men, who have now reached the point where they can take their ways to the rest of the universe!

It has one moon, simply named The Mun.

Physical Characteristics:

• 
  [li]Radius: 600 km[/li]
  [li]Rotation Period: 6 hours[/li]
  [li]Atmospheric Composition: 30% Oxygen, 65% Nitrogen, 5% Other elements[/li]
  [li]Surface Composition: Silicates, liquid water oceans present[/li]
  [li]Surface Gravity: 1g[/li]
  

Orbital characteristics:

• 
  [li]Period: 109 days [/li]
  [li]Semi-Major Axis: 0.09 AU[/li]
  [li]Eccentricity: 0[/li]
  [li]Inclination: 0[/li]
  

I have one slight problem with the Surface Gravity of Kerbin seeing as the Kerbals are shorter than a natural human I believe that the G scale should also be adjusted accordingly. That is unless, of course, this is using the gravity of Kerbin as a reference (In contrast to the Gravity of Earth which we use with the term Gees) if this is the case i would like to be informed in the OP Thank you for taking time to read this and i really love your Creations.

[TheDeparted]

i doubt Kerbin is that small, if anything, kerbin is BIGGER than earth

also, earth is bigger than whats shown, luna is 1/6th size of Earth

Im sorry to say but your thinking of the gravity of the Moon there Buddy >.>

[NovaSilisko]

I have one slight problem with the Surface Gravity of Kerbin seeing as the Kerbals are shorter than a natural human I believe that the G scale should also be adjusted accordingly. That is unless, of course, this is using the gravity of Kerbin as a reference (In contrast to the Gravity of Earth which we use with the term Gees) if this is the case i would like to be informed in the OP Thank you for taking time to read this and i really love your Creations.

I\'m not quite sure, actually. I like to think that Kerbals just evolved shorter.

[stefan1114ever]

Hey nova

I was asking myself when the new planet concepts are done

Are the planets behind kerbin coming soon?

[NovaSilisko]

Hey nova

I was asking myself when the new planet concepts are done

Are the planets behind kerbin coming soon?

The whole effort kinda was stopped due to the difficulty of properly making all of the things in a readable format on a forum... I think I\'m just going to release the Celestia addon file so people can look around it themselves.

[Cepheus]

Splee.

[stefan1114ever]

The whole effort kinda was stopped due to the difficulty of properly making all of the things in a readable format on a forum... I think I\'m just going to release the Celestia addon file so people can look around it themselves.

Thanks

It\'s a great idea for a add-on in celestia

Can you post the name of the add-on

When it is done?

[closette]

Just saw this thread for the first time. You can\'t make up the composition of Kerbin\'s atmosphere to be similar to Earth\'s - there are constraints from what we already know from experiment. Bear in mind that the scale height of Kerbin\'s exponential atmosphere is 5 km (verified in this thread: http://kerbalspaceprogram.com/forum/index.php?topic=5623.msg86679)

And since scale height is related to the atmosphere\'s composition, temperature and surface gravity by H=RT/Mg : http://en.wikipedia.org/wiki/Atmospheric_models#Isothermal-barotropic_approximation_and_scale_height

...that implies that the average molecular weight of Kerbin\'s atmosphere M must be around 46, compared to Earth\'s 29, so there has to be a component of some heavy molecule present (SF₆, Xenon...) to bump up this average.

As a result, the Kerbals probably have deeper voices that one would expect from their small size!

[thorfinn]

...that implies that the average molecular weight of Kerbin\'s atmosphere M must be around 46, compared to Earth\'s 29, so there has to be a component of some heavy molecule present (SF₆, Xenon...) to bump up this average.

As a result, the Kerbals probably have deeper voices that one would expect from their small size!

Closette, I just wanted to say that I really envy your enthusiasm

Back when physics was mostly a game for me, I would probably have been working out data on Kerbin just like you and perfecting Kerbin-Mun trajectories on so many sheets of paper... Now that it\'s my job, I get enough of it in the lab that I\'m not really in the mood of doing much calculations when I come back home and play KSP. But sometimes you manage to find very interesting things; the first-order atmospheric model you just linked was new to me, for example (and it\'s the kind of thing where you go 'oh, but that\'s obvious!' AFTER you\'ve seen it...)

And by the way, following your numbers, Mach 1 at sea level on Kerbin is 270 m/s, assuming normal Earth temperatures. Nice. Maybe still a tad high from a gameplay aspect... but it\'s such a nice derivation

[Cepheus]

...there has to be a component of some heavy molecule present...

[Satellife]

I remain amused that all of you are treating KSP like a hard-science fiction game, when it is clearly soft sci-fi, possibly even fantasy.

[thorfinn]

I remain amused that all of you are treating KSP like a hard-science fiction game, when it is clearly soft sci-fi, possibly even fantasy.

The game we play is, what are the implications of the numbers that Harv chose? What neat physical ideas can we learn from them?

We know that the density of Kerbin is fantastically high, that scaling down the Solar system by 91% doesn\'t work... but learning how and why Kerbin is impossible is very instructive and entertaining. For us at least

[Satellife]

The game we play is, what are the implications of the numbers that Harv chose? What neat physical ideas can we learn from them?

We know that the density of Kerbin is fantastically high, that scaling down the Solar system by 91% doesn\'t work... but learning how and why Kerbin is impossible is very instructive and entertaining. For us at least

Oh, I wasn\'t talking about the physics of the game\'s framework, or even the technology itself.

A political regime with this large an interest in space is impossible.

[closette]

Well some of us like physics And the more I learn about the KSP world, the deeper my admiration for the developers who did an amazing job putting it together. Some of the planetary properties may be unrealistic, but none of them I have found to be 'ridiculous', which makes KSP an excellent training ground for future rocket scientists, in my opinion.

@thorfinn you are too kind, I am standing on the shoulders of giants here. A quick update on Kerbin\'s atmospheric properties (some of the numbers in the old thread were off by arbitrary factors of 2 or sqrt(2)):

Scale height = 5000 m as measured, and below I assume that 1 command pod mass = 1000 kg, and therefore 1 Kerbal unit of thrust = 1000 N. Also assume that T ~ 300 K (liquid water oceans, green grass, snow on the mountains, clouds):

Sea-level pressure = 490 000 N/m² (just under 1/2 our atmosphere)

Sea-level density = 10 kg/m³ (about 10 times Earth\'s)

Average molecular weight ~ 50.8 g/mol

Sound speed ~ 221-262 m/s (for gamma values in the range 1.0-1.4)

SF₆ doesn\'t just deepen our Kerbals\' voices - they need it for the strong greenhouse effect given their puny sun - which is one reason I prefer it as constituent of the atmosphere over Xenon. The rest could be mainly CO₂ and O₂ (which is evident from fiery explosions!).

If I\'ve done my sums right, one possible mixture consistent with all we know so far would be: 10% SF₆, 27% O₂, and 63% CO₂. We humans could pay them a visit!

[thorfinn]

If I\'ve done my sums right, one possible mixture consistent with all we know so far would be: 10% SF₆, 27% O₂, and 63% CO₂. We humans could pay them a visit!

With exopacks, like on Pandora

Oh, and that much CO₂ also makes atmospheric entry harder (pages 3-4) than in air, which is good 'story-wise' (since we reenter so slow...)

[fairtonybeta]

makes atmospheric entry harder (pages 3-4)

this is amazing, thankyou so much.

[Cepheus]

If I\'ve done my sums right, one possible mixture consistent with all we know so far would be: 10% SF₆, 27% O₂, and 63% CO₂. We humans could pay them a visit!

So what you\'re saying is, we should pack our bags, and go to Kerbin?

[closette]

So what you\'re saying is, we should pack our bags, and go to Kerbin?

Ah, perhaps somebody already went there, which would explain the '11' painted on the side of the VAB, the use of English in telemetry, and the whole launch complex construction.

[Kryten]

If I\'ve done my sums right, one possible mixture consistent with all we know so far would be: 10% SF₆, 27% O₂, and 63% CO₂. We humans could pay them a visit!

Concentrations of CO₂ higher than around 10% are lethal...

[thorfinn]

Ah, perhaps somebody already went there, which would explain the '11' painted on the side of the VAB, the use of English in telemetry, and the whole launch complex construction.

There are some rumours that somebody reached them before their discovery of space travel:

The details of the voyage are unknown, as are those of the breathing filters that he undoubtedly needed.