Talk:Kerbol

I know the sun has been called kerbol for a long time, but ingame, it is simply 'the sun'. Kerbol only exists in the memories of old timers. This should be mentioned here.

M class? More like K...

Based upon the distance to Kerbin, to have earth-like temperatures the star would need to be a low K class minimum. K class stars are still red, so just because 'Red Dwarf' is commonly associated with M class doesn't mean that all red dwarfs are M class.

Just saying, I think it's more likely that kerbol is a K class Main sequence star (KnV, where n is either 6,7, or 8.) --Mocha2007 (talk) 16:05, 18 September 2012 (UTC)

I have been doing some crude maths of my own on this, and based on the Mass of Kerbol and thus the Luminosity, I see this as being something more like high G, around 8 or 9. Though it does look like it is a very small star for such mass and luminosity. Though This is based of of the mass and radius given from this wiki, which I do not know how accurate they are. Thecoshman (talk) 12:22, 9 October 2012 (UTC)

Use of Planet Box

As the very name suggest, the planet box is for planets, much of the information it would contain is 'N/A' when dealing with stars. Could someone with a better mastery of templates make a more applicable 'star box'. It may seem a bit redundant for the now, but I dare say eventually inter-stellar travel will be possible. Thecoshman (talk) 08:21, 9 October 2012 (UTC)

Expression Error: Unexpected < Operator

Ok... I wanted to change the class of Kerbol form star to K-Class Star. It worked, but in bright red letters popped the message: "Expression Error: Unexpected < Operator". So like the good person i am, i reverted my changes, but it stayed. I think it has something to do with the Orbital Period Hours. Anybody know what the heck is going on???--Azivegu (talk) 19:24, 22 October 2012 (UTC)

Dutch link

Could somebody link up the Dutch language Kerbol Page to this one like the Russian one is done???--Azivegu (talk) 19:25, 22 October 2012 (UTC) http://wiki.kerbalspaceprogram.com/wiki/Kerbol/nl - but im translating it: WIP --ExtremeTrader (talk) 5:54, 19-12-2013 (BST)

Kerbol

Though it probably is indeed a K-class, it may also be a white dwarf. If Kerbol actually existed, it would be a T or Y class brown dwarf, because no star that small can undergo nuclear fusion.--Mocha2007 (talk) 22:25, 28 October 2012 (UTC)

Trivia Terminology

most of the terms used in the trivia and the best ways of getting to Kerbol are terms that I myself don't understand. I'm going to look them up, but as a suggestion, I'd reccomend a link to a wikipedia article for what they mean

Answer: http://wiki.kerbalspaceprogram.com/wiki/Terminology --ExtremeTrader (talk) 00:02, 19 December 2013 (CST)

Name

The name of the Star in-game is "Sun", so I'm unsure as to why the name of this page is "Kerbol", surely it should be the same as in-game? — Preceding unsigned comment added by Ted (talk • contribs)

It's partly historical reasons (the name "Kerbol" predates the star being an object by some time), and as a way to distinguish the star from our Sun (It's frustrating getting newbies to realize that Kerbin != Earth, Mün != Luna, etc). The name is fairly entrenched in the game population at this point, though I wouldn't mind if Squad picked a wholly new one... UmbralRaptor (talk) 22:25, 12 February 2013 (CST)

I support this. Calling the page "Kerbol" does nothing except help spread misinformation Holomanga (talk) 09:38, 27 May 2013 (CDT)

Now but this isn't the real Sun. Luckily you can differ between Kerbal celestial bodies and real ones by the name, except for the Sun. As there is a redirect from Sun although those who searching for it get redirected here. And it is stated that it is also called the Sun in the first sentence. But I made it clearer that “the Sun” is the official name. — xZise [talk] 11:38, 27 May 2013 (CDT)

I'd expect that one a website called "Kerbal Space Program Wiki", people would be aware that the page that they were looking at referred to the Sun from KSP, though the extra clarity is good. Holomanga (talk) 11:33, 28 May 2013 (CDT)

Rotation speed

If you go into interplanetary space, and check the 'surface' speed indicator, you will see the surface is spinning at well over 700 km/s.. should this be updated? — Preceding unsigned comment added by Kahlzun (talk • contribs)

The orbital velocity at the surface is okay 67 km/s which would result in the sun ripping apart. — xZise [talk]

The "surface" indicator on the navball actually indicates how fast you move in relation to the surface. --dgelessus ^{(talk, contribs)} 11:35, 27 May 2013 (CDT)

Oh and also this. To measure you place the craft at a synchronous orbit (surface velocity = 0) and then your orbital velocity tells the rotational velocity of Kerbol. — xZise [talk] 11:40, 27 May 2013 (CDT)

Outdated Surface height

Unless I somehow read the page wrong, the invisible surface height of ~4500 km is outdated as of 0.21.1, proved by my small sundiving probe currently at ~4000 km. - JonSpace_CEO (i'm also unsure of how to timestamp as i'm new to the wiki)

Just went back and checked, the new lowest altitude is ~1300 meters , not ~4500 km (with screenshots to prove it)

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  You will probably have to click on the picture if you want to see for yourself, but the altimeter reads 3999 km

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  The last picture of the probe, at ~1000 km, before it crashes into Kerbol.

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  The crash itself, the altimeter is not to be trusted as it is changing rapidly both up and down.

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  The mission report after the crash, with the altimiter reading 1284 meters.

Note: You can sign your posts with --~~~~.

What does the altimeter read, when you crash somewhere else into Kerbol? If it is almost always about 1.3 km this should be fixed. — xZise [talk] 03:51, 8 September 2013 (CDT)

Can we possibly get someone else to do it as i don't really feel like repeatedly crashing probes into the sun (it gets kinda monotonous) also, i'm fairly busy with some stuff right now so i can't do it anytime soon. --JonSpace CEO (talk) 04:59, 12 September 2013 (CDT) (thanks for the tip on signing btw)

Confirmed, I blew up around 1300m as well. --Dentarthurdent (talk) 18:05, 23 October 2013 (CDT)

All engines have a TWR below 1 at the surface?

I haven't tested it yet, but why is the TWR of all engines below 1? In the parts article are all engines listed with their TWR on Kerbin's surface. But the surface gravity is only listed as 17.1 m·s⁻² or ≃ 1.76 g. So the TWR on Kerbol is the TWR of Kerbin divided by 1.76, which means that each engine with a TWR at Kerbin greater than 1.76 will have a TWR at Kerbol's surface greater than 1. And most engines have a listed TWR of 1.76. So is there another “force“ at work, or is this simply outdated? It appears that prior to 0.14 you could drop below the surface and thus increasing the TWR drastically, although I'm not sure what the gravitational acceleration is at the center. — xZise [talk] 18:33, 6 October 2013 (CDT)

Yes, this seems incorrect. Assuming a spacecraft consisting of just the engine with a massless fuel source, the Mainsail should have a TWR of 14.1 at the surface. Skipper would have a TWR of 9.2, and even the nuclear engine would have a TWR of 1.6. I haven't checked all of the engines but it looks like most would easily work for a lander. Mocha2007 (talk) 11:06, 14 October 2013 (CDT)

spectral classes

“

It has the temperature of a K Class main sequence star, the radius of a M class star, the luminosity of a G class star, and the mass of a sub-brown dwarf. In reality, such a star cannot exist as the minimum mass of a star is approximately 75 times the mass of Jupiter, a full power of ten higher than that of Kerbol. — The article as of revision 28199

”

No offense, but I don't think the writer of this sentence really knows how to read an HR diagram. the type or class of a star denotes the temperature and color of a star, not the luminosity or the size. For example, the "radius of an M-class star" as mentioned above, can vary anywhere from the size of a red dwarf like Barnard's Star, to a red supergiant like Betelgeuse. Similarly, as the type denotes temperature and not luminosity, G type stars can be nearly anywhere on the luminosity range, from dim yellow dwarfs to bright yellow supergiants. I'm not sure about exactly what type of star Kerbol is, but this sentence needs to be changed.-Cpthunt (talk) 19:56, 4 November 2013 (CST)

As you already created an account you are able to fix it yourself. Of course you can still add a note in the discussion to explain it more detailed. I've edited your original comment to avoid that the MediaWiki treats your quote as code (leading whitespaces). — xZise [talk] 10:59, 5 November 2013 (CST)

I really have to disagree with everyone calling Kerbol a K-class star. I agree that, based on Kerbin's temperature, Kerbol's luminosity must be about 3E+24 watts. However, given its surface area, that works out to a luminosity of 3.5E+6 watts/m^2. Using Stefan-Boltzmann law, this computes to a surface temperature of 2800 K, which clearly makes it an M-class star. Can someone show me how you're coming up with K-class?--OhioBob (talk) 1:20, 17 January 2015 (UTC)

And I really disagree with you. The sentence was correct, the temperature always determined by the color see this, and the luminosity determines the emitted power. NWM (talk) 18:33, 17 January 2015 (CST)

If the 2,8 kK mentioned by OhioBob are the w:effective temperature mentioned in w:Stellar classification#Harvard spectral classification it'd classify as a M class star. As I understand it, the color and temperature are linked (higher temperature means white and then blue) and either the temperature at Kerbin is wrong, Kerbin's distance, Kerbol's size or Kerbol's color ;) I guess Squad just didn't thought that there would be people who would try to determine the star's class. — xZise [talk] 18:51, 17 January 2015 (CST)

Although it is true there is a temperature-color relationship, spectral class is determined by temperature. Color can be used as an indicator of temperature, but temperature can be determined in other ways. In this case the temperature can be determine mathematically based on other known factors (Kerbin's temperature & distance, and Kerbol's size). This results in a computed surface temperature of 2800 K, making Kerbol a M class star. The math should be the determining factor, not what it looks like. Kerbol's yellow-orange color is simply a mistake given what we can mathematically determine about it. — OhioBob (talk) 9:06, 19 January 2015 (UTC)

Let me also add that if Kerbol were a K class star, it would have a surface temperature of at least 3700 K. At this temperature its luminosity would be about 9 Yotta-watts. This would place Kerbin well inside of the star's habitable zone. Kerbal life as we know it would not be possible if Kerbol were K class. — OhioBob (talk) 16:58, 19 January 2015 (UTC)

At first - in the Kerbal World we cannot estimate the power emission of the Kerbol, because this world is not physically consistent - the solar panels power generation doesn't follow the inverse square law, neither the celestials surface temperature. You will get different result by each of the celestials. By the parameters of Laythe it would even more then ~5000K derived from the color!— Preceding unsigned comment added by NWM (talk • contribs) 07:09, 20 January 2015‎ (UTC)

Yeah the thermometer isn't really useful to get accurate temperature readings, but there is liquid water at Kerbin's surface (at normal pressure) which limits the output range of the Sun. But then there is obviously the problem on how to explain the liquid water at Laythe's surface. — xZise [talk] 05:41, 20 January 2015 (CST)

You're definitely right about the physical inconsistency of the solar system. However, since the article gave Kerbol's luminosity, and I didn't see anybody questioning that, I thought we should make the star's temperature (and spectral class) consistent with the luminosity. Even though the system is inconsistent, we should at least strive for some internal consistency in the reported characteristics of Kerbol. —OhioBob (talk) 22:00, 20 January 2015 (CST)

Hay! I'm here and I am questioning your luminosity results, because there is no valid and consequent thermal laws in the Kerbal world what you have used. There ara only definite the color (T) and the size (A) can be used for. NWM (talk) 01:45, 21 January 2015 (CST)

The article clearly states that Kerbol has the color of a K class star. It also states that the luminosity is "based on planet Kerbin's temperature", the temperature is "based on its size and luminosity", and the computed temperature is that of a M class star. All of that is true. It doesn't say that the luminosity and temperature are absolute facts. They are approximations and the basis for those approximations is clearly stated. Likewise, it can't be stated as absolute fact that Kerbol is K class, only that it has the color of a K-class star. I really don't see a problem with the article as currently written. (I moved that part about Kerbol's color up to the second sentence in the paragraph to make it more conspicuous.) — OhioBob (talk) 10:57, 21 January 2015 (CST)

Luminosity and Temperature

I think I’ve derived a better estimate of Kerbol's luminosity and temperature using the planets Eve, Kerbin and Duna. There’s clearly some guesswork in this but I’ve tried to make reasonable assumptions. In order to calculate luminosity in this manner, two things are required: the black body temperature and the albedo of the planets.

A planet with an atmosphere will have a surface temperature higher than its black body temperature due to the greenhouse effect. For example, Earth’s average surface temperature is 288 K while its black body temperature is 254 K. It seems that a reasonable estimate of black body temperature can be found by taking an average of the minimum and maximum temperatures listed in each planet’s Wiki article. By this method we get a temperature for Kerbin of 263 K, while its surface temperature is 293 K (values that are comparable to Earth). Doing the same for Eve and Duna we obtain temperatures of 328 K and 233 K respectively.

One way to estimate albedo is from the color of the planets, obtaining about 0.1 for Eve and Kerbin and about 0.25 for Duna. However, this is for the surface only. Even though the planets are depicted without cloud cover, I think we have to assume clouds will be present. Since Kerbin is an analog for Earth and appears very Earth-like, I’m assuming it has an Earth-like albedo of 0.3. Likewise, Duna is an analog for, and looks very much like, Mars, though with much larger ice caps. Starting with Mars’ albedo of 0.25 and making an adjustment for the greater ice cover, I estimate an albedo of 0.35. Although Eve is in many ways an analog for Venus, its surface appearance and composition is very different. Guessing its albedo is a crapshoot, so I just assumed the same as Kerbin at 0.3.

From these temperatures and albedos we can compute the luminosity of Kerbol. Using the values for Eve, Kerbin and Duna respectively, I compute luminosities of 4.56E+24, 3.60E+24 and 5.55E+24 watts. Dividing the luminosity by the surface area of Kerbol we obtain the irradiance, from which we can compute temperature. The respective temperatures work out to be 3109, 2932, and 3267 Kelvin. As you can see, these numbers are reasonably consistent (luminosity varying only ±21% from the average). Taking an average of these numbers and rounding off, I think we can call the luminosity approximately 4.5E+24 W and the temperature approximately 3100 K.

The other bodies with atmospheres are Jool and Laythe. Jool has the highest maximum temperature of all the planets, though this can be rationalized. Since Jool is an analog for a Jupiter-like gas giant, it would be generating internal heat from gravitational compression. The outlier is Lathye, which has much higher temperatures than it should base solely on its distance from Kerbol. One possible rationalization for this is that Laythe is heated by tidal flexing due to its close proximity to Jool. — OhioBob (talk) 14:55, 22 January 2015 (CST)

There is no longer a need to speculate about Kerbol's surface temperature. The temperature is given in CelestialBodies.config as 5840 K. However, Physics.config gives the solar luminosity at Kerbin as 1360 W/m². Working backward from that yields a luminosity of 3.16 yottawatts and a surface temperature of 2840 K. Therefore, we have an unavoidable internal conflict between the given temperature and the given luminosity. I've edited the article to include this new information. — OhioBob (talk) 19:38, 19 May 2015 (UTC)

Help with File Upload?

I created a graph showing the temperature of Kerbol's atmosphere vs. altitude, which I want to use for this article. However, when I attempted to upload it I got an error reading "Fatal exception of type MWException". Can anybody help me with this problem? — OhioBob (talk) 19:45, 19 May 2015 (UTC)

We are currently experiencing migration problems so you have to wait unfortunately. — xZise [talk] 16:36, 21 May 2015 (UTC)