# Kerbin is really dense

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Jeb's Bane - a specific named threat to Jeb such as ore that is too heavy.

Jeb's bane - a cause of great distress to Jeb, such as sitting in a perfectly good rocket doing  nothing and being told to do nothing, aka the bane of Jeb's life.

#WhatDidWeInventCapitalsForAnyway

Edited by KSK

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On ‎08‎/‎02‎/‎2018 at 8:27 AM, JP_Magoo said:

... Kerbin is 10 times smaller than earth, and to simulate the same gravity it must be 10 times as dense...

hello

I don't think this assumtion is correct... what formula do you used to extract such result ?

10 times smaller (distance) means 1000 times less volume (10^3), on top of that the actual radius (distance to the center of mass at sea level) also influence the evaluation...

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No, he's @JP_Magoo is correct.

Surface gravity is proportional to M/R^2. Mass is proportional is d*R^3. So, surface gravity is proportional to  d*R. If you divide R by 10, you have to multiply d by 10 to keep the same surface gravity.

My favorite armchair astronomy fact is related to this. Tidal forces are proportional to M/D^3 (D is distance to body.) M is proportional to d*R^3, so  tidal forces are proportional to d * (R/D)^3.  Now R/D is (to good approximation) the angle the object makes in the sky. So since the moon and the sun have the same size in the sky, (to good approximation) , the ratio of the tidal forces from each is the same as the ratio of their densities. You can measure the tides to determine that the sun's impact is about half the moon's. So the sun is half as dense as the moon.

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You scientists! Let me explain.

*Clears throat*

The planet was made when the ancestors of Kerbals, Kerbs, made a new metal to launch rockets.

This metal was an alloy of lead and osmium injected with tungsten.

The waste was pumped out into space, where it combined with other chunks of the metal, which is now in Kerbin's core, which is why Kerbin is called Kerb-In.

The metal was so common, that it made it into the Kerbs' body.

And made it into the Kerbals' body.

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17 hours ago, samstarman5 said:

I have, as a matter of fact. Doesn't change what I stated. Maybe you should read up the definition of bane before making assumptions.

If you do not want people to make assumptions maybe your posts should make more sense, or even just be funny.

I bet you are fun at parties.

"Actually, we should not use the words `Happy Birthday` when congratulating someone on the anniversary of it. We should congratulate them on the anniversary of the event, not the event itself."

Oh how we laughed.

Wait, no we didn't.

Just to be clear a `bane` is a cause of great distress or annoyance. For example a Balrog would be a bane to dwarves. A heavy rocket would be a bane to Jeb.

As such, if the core of Kerbin were to be made of an old core from a neutron star, if you delved too deeply and too greedily for your ore, from which you would make a rocket, then it would be heavier than normal ore as it contains small amounts of degenerate neutronium. If you made your rocket from this ore, it would have a poor TWR, and this is what we find in KSP. This would frustrate an astronaut who wanted to reach orbit due to the rocket equation.

It would be Jeb's Bane.

YOU might want to read up on the definitions of words before you incorrectly correct others when they use words correctly again...

I assumed you had not read the book due to your comment bearing no relation to the bane of the dwarves, Tolkien, or even the correct usage of the word.

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18 hours ago, John FX said:

As such, if the core of Kerbin were to be made of an old core from a neutron star, if you delved too deeply and too greedily for your ore, from which you would make a rocket, then it would be heavier than normal ore as it contains small amounts of degenerate neutronium. If you made your rocket from this ore, it would have a poor TWR, and this is what we find in KSP. This would frustrate an astronaut who wanted to reach orbit due to the rocket equation.

Trouble is, small amounts of neutronium don't happen.  The neutron degeneracy pressure is so high that you need at least 1.4 solar masses of material to hold it together in that form.  Otherwise it explodes with literally the force of a supernova.  Also the stuff is so dense you'd find a very small core of it at the centre of the planet, well below the region where thermal problems would stop drilling operations.  Not to mention the giant permanent forcecage effect from the insane wizard responsible, holding such a tiny amount of the stuff together under such obscene pressure.

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1 minute ago, Archgeek said:

Trouble is, small amounts of neutronium don't happen.  The neutron degeneracy pressure is so high that you need at least 1.4 solar masses of material to hold it together in that form.  Otherwise it explodes with literally the force of a supernova.  Also the stuff is so dense you'd find a very small core of it at the centre of the planet, well below the region where thermal problems would stop drilling operations.  Not to mention the giant permanent forcecage effect from the insane wizard responsible, holding such a tiny amount of the stuff together under such obscene pressure.

See?

There you go trying to explain things with sense and logic in a game about little green men on a planet 10 times too small who have no buildings except those for making and flying spacecraft and planes.

Obviously it cannot happen here in the real world with all our `physics`, but in the world made from pixels, anything can happen.

To see which world you are in, try to take apart anything in the VAB menu, if you are in the world made from pixels you will find it is just a solid part, with no internal components. It makes thrust purely by `magic`. If you can take it apart and see a mechanism that makes it work, you are in the real world. In the pixel world, it is completely possible to have just a smattering of degenerate neutronium evenly spread all through the planet...

Maybe the same wizard is responsible for both effects?

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3 minutes ago, John FX said:

See?

There you go trying to explain things with sense and logic in a game about little green men on a planet 10 times too small who have no buildings except those for making and flying spacecraft and planes.

HEH, did you not see my other post in this thread?  So much math.

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On 2/14/2018 at 11:07 AM, Archgeek said:

Trouble is, small amounts of neutronium don't happen.  The neutron degeneracy pressure is so high that you need at least 1.4 solar masses of material to hold it together in that form.  Otherwise it explodes with literally the force of a supernova.  Also the stuff is so dense you'd find a very small core of it at the centre of the planet, well below the region where thermal problems would stop drilling operations.  Not to mention the giant permanent forcecage effect from the insane wizard responsible, holding such a tiny amount of the stuff together under such obscene pressure.

Meh, I can perceive The Sun™ despite the distance penalty, so I'm obviously so overpowered that I could probably cast such a force cage as a damned cantrip.  A quickened silent still maximized cantrip.  As a fighter.

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Meh, I can perceive The Sun™ despite the distance penalty, so I'm obviously so overpowered that I could probably cast such a force cage as a damned cantrip.  A quickened silent still maximized cantrip.  As a fighter.

Maybe, but permanent spells cost XP.  And no one wants to give up precious experience points.  Especially for something so frivolous as a quickened, silent, stilled, repeatedly-extended-until-about-city-size force cage.  You could train an army to at least level 10 with all that exp.

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On 2/8/2018 at 5:19 AM, Brikoleur said:

is Kerbol.

Actually, no, it's not. According to the wiki page about the sun, 'There is no such thing as Kerbol outside of the community forums and wiki.' (Use ctrl+f to verify this.)

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On 2/8/2018 at 2:51 AM, swjr-swis said:

The entire upper crust of Kerbin consists of highly compacted kerbal and craft remains dropped from the skies, after aeons of constantly trying to get to orbit.

Iow: Kerbin is quite literally made out of compacted Kerbal droppings...

(just one theory)

Very dense poop

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On 2/15/2018 at 11:27 PM, Archgeek said:

Maybe, but permanent spells cost XP.  And no one wants to give up precious experience points.  Especially for something so frivolous as a quickened, silent, stilled, repeatedly-extended-until-about-city-size force cage.  You could train an army to at least level 10 with all that exp.

Actually I play Pathfinder, so it's just gold to me

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