[minor] Why is Minmus Frozen?

[duckunlimited2]

I think the existence of a frozen minmus has a better chance in existing if we consider that the methane is not just pure methane, but a compound combined with other substances. I did a quick five minute research and found something promising.

WHAT IF THE METHANE EXISTED AS METHANE CLATHRATE!

Methane clathrate are methane molecules caged in a water molecule crystal latice. Or in other words methane frozen inside water ice.

Water, being a heatsink, would better keep a solid, crystal state than just pure methane meaning it can exist in warmer areas, like closer to a star. To better get a picture on what temperatures it can exist in, methane clathrate has been found in large quantities in permafrost conditions on earth and under the ocean seabed. Yeah its cold for earth standards but its hot if you compare it to space cold.

Now, its been said that methane clathrate forms in the outer reaches of earth\'s solar system so I would speculate that minmus is actually a captured 'asteroid' or the equivalent of a kuiper belt object in the kerbal universe that was slingshoted into the inner kerbol solar system and captured by kerbin.

I also like this theory because it brings water to an already very useful moon. Methane based rocket fuel is being developed by NASA, meaning that minmus has the potential of being a very useful refueling station. Bring water to the equation and it can also provide water and oxygen to space bound ships.

Here are my wiki links if you are interesting in learning about methane clathrate and clathrate hydrates:

http://en.wikipedia.org/wiki/Methane_clathrate

http://en.wikipedia.org/wiki/Clathrate_hydrate#Hydrates_in_the_Universe

[EDF]

Except in his .16 devblog HarvesteR has called them frozen methane lakes.

Edit:methane freezes at -296.5 degrees Fahrenheit. Someone want to fly out and .get surface day temperature readings?

Do you even kelvin?

[Misterspork]

-snip-

Your 'cold of space' comment, that actually is only true on the dark side of a planet.

An atmosphere-less planet/moon can be several hundred degrees on the day side, but much colder on the night side. A planet with atmosphere stays mostly the same temperature because of conduction/convection, whereas an atmosphere-less planet does not have those methods, and rapidly heats up and rapidly cools down.

[sss]

Maybe its made out of a special material, like minoeralus(get what i mean with minoeralus?)

[Vanamonde]

I notice that at night on Minmus you can see the stars and milky way, but they fade from view when the sun is out. Since in real life that would only happen if an atmosphere was scattering the sunlight to overwhelm the lesser lights, does that imply that Minmus has a considerable atmosphere? Or is it just an aspect of the game\'s lightning effects? I\'ve had a ship orbiting 4000-6000m for game-days, with no apparent slowing due to air resistence.

The same conditions apply on Mun, which I think is supposed to be a scaled-down version of our own Moon, and therefore would seem to be airless by intention. Then again, it\'s larger than Minmus, so if Minmus does have an atmo, why not Mun?

[Awaras]

some more cheating later, I got a Kerbal on Minmus. Here\'s me jetpacking around over a frozen methane lake:

HarvesteR @ http://kerbalspaceprogram.com/forum/index.php?topic=13530.msg219016#msg219016

Straight from the man himself.

Heh, flying over a frozen methane lake at a balmy 44 degrees C...

[samstarman5]

I notice that at night on Minmus you can see the stars and milky way, but they fade from view when the sun is out. Since in real life that would only happen if an atmosphere was scattering the sunlight to overwhelm the lesser lights, does that imply that Minmus has a considerable atmosphere? Or is it just an aspect of the game\'s lightning effects? I\'ve had a ship orbiting 4000-6000m for game-days, with no apparent slowing due to air resistence.

The same conditions apply on Mun, which I think is supposed to be a scaled-down version of our own Moon, and therefore would seem to be airless by intention. Then again, it\'s larger than Minmus, so if Minmus does have an atmo, why not Mun?

The light from the sun floods out any secondary light, like from stars or other forms of enlightened gas. Ask any astronaut how easy it is to see the stars and they will tell you that it is impractical, unless you have a stovepipe along. Block out the sun and the view of space is awesome to behold. It doesn\'t matter if you are looking through atmosphere or vacuum. You would need to get a few more AU away from the sun before uninterrupted view of the rest of the sky is possible with unaided sight. Get a long pipe, and you can see the stars during the day on Earth.

And it isn\'t the Milky Way in Kerbin\'s space. It could be a neighboring galaxy, though what type of one remains a hot topic of discussion. I think it is an enhanced barred spiral.

Cheers!

[Khrissetti]

That whole \'look through a pipe and see the stars\' is a myth. the atmosphere of Earth scatters the sunlight through the atmosphere, which makes it appear blue as well.

The inability to see stars during the day on Minmus is possibly similar to the reason you can\'t see the stars in the original Appollo landings, the light from the sun and reflected off the blinding surface of the Moon swamps the relatively small light from the stars.

[hebdomad]

Or maybe it\'s covered in GLASS. Not frozen liquid...

[Nibb31]

They get it from the temperature outside

There is no temperature outside if you\'re in a vacuum. If you stick a thermometer outside a spaceship, you are not measuring the temperature of space. You are measuring the temperature of the thermometer.

Space isn\'t hot or cold, because it isn\'t anything. It\'s void. If there is no matter, you can\'t measure the properties of that matter.

What you can measure is the temperature of the soil or the temperature of the space ship parts. In practice, stuff facing the sun is hot. Stuff in shadows is cold. In space, these temperatures can get extreme, because there is no convection to moderate the temperature.

Because of this, the possibility of liquid water on the surface of a moon with no atmosphere is zero. As soon as the sun hits, it would vaporize. Water can only be liquid within a very narrow temperature range. Similarly, there can be no frozen lakes, even on the dark side, because a flat surface implies that it was once liquid, which is not possible.

[Khrissetti]

Minmus could be similar to Europa, in having a frozen crust over a liquid mantle. perhaps the mountains could have arisen from the impact of rocky materials during the freezing of Minmus sometime in its past?

[4 IN 1]

There is no temperature outside if you\'re in a vacuum. If you stick a thermometer outside a spaceship, you are not measuring the temperature of space. You are measuring the temperature of the thermometer.

Space isn\'t hot or cold, because it isn\'t anything. It\'s void. If there is no matter, you can\'t measure the properties of that matter.

What you can measure is the temperature of the soil or the temperature of the space ship parts. In practice, stuff facing the sun is hot. Stuff in shadows is cold. In space, these temperatures can get extreme, because there is no convection to moderate the temperature.

Because of this, the possibility of liquid water on the surface of a moon with no atmosphere is zero. As soon as the sun hits, it would vaporize. Water can only be liquid within a very narrow temperature range. Similarly, there can be no frozen lakes, even on the dark side, because a flat surface implies that it was once liquid, which is not possible.

Well, to be more technical, even the 'space' we all think about is not a complete vacuum, there is still substance that may or may not be bound by gravity wandering around.

Another technical point is that temperature is the measurement of how much energy a said substance contain, the higher temperature the said substance have, the more energy it contain, and the faster it moves around.

With that said, when we said we measure the temperature of space, we are technically measuring the temperature of free moving substance in that area unless otherwise specified.

P.S. Speaking of which, you cannot get absolute zero reading even in the darkest place of the known universe, because you will always be measuring CMB(around 3 K),

P.S.2 That is, however, not as cold as some of the component working inside LHC, which is only 2K, and at 1K, Boomerang Nebula is the coldest naturally existing place in the known universe.

[CaptainArbitrary]

And precisely where the hell do they get this information, the creator\'s ass?

FlightIntegrator.getExternalTemperature(). Don\'t be a jerk.

There is no temperature outside if you\'re in a vacuum.

There are two common misconceptions there. First, that a vacuum can\'t have a meaningful temperature. And second, that space is a vacuum.

If you want to be rigorous about it, the temperature of any volume of space can be defined as the equilibrium temperature of a blackbody in that volume. Everything made of matter radiates heat away as electromagnetic radiation —light, essentially. You know how a piece of metal glows when it\'s hot? Same thing, only it happens no matter what the temperature of the thing is. It\'s just at 'normal' temperatures, things glow in the infrared, which we can\'t see. Even very cold things glow in the radio band. Only at absolute zero is the energy flux of blackbody radiation zero, and of course absolute zero is physically impossible.

So yes, a vacuum most certainly has a temperature. It\'s the temperature in which a perfectly non-reflective body would be at equilibrium, absorbing as much energy as it emits through blackbody radiation.

In our universe, the temperature of the vacuum is about three degrees absolute. That\'s because the universe is filled, wall to wall, with the drastically redshifted radiation from the epoch of recombination that happened at the end of the Big Bang. Basically, the universe has an ambient light level, only that light is way down in the microwave part of the spectrum so we can\'t see it with our eyeballs. When that ambient light, left over from creation, hits stuff, it heats that stuff up, meaning a perfect blackbody would, in a perfect vacuum, have an equilibrium temperature of about three degrees.

Course, the other misconception is that there\'s such a thing as a perfect vacuum. On any useful scale —any scale larger than the wavelength of an electron —there are no perfect vacuums for very long. There\'s always stuff there, even if they\'re just individual protons, bouncing around and heating things up. So the real equilibrium temperature of a blackbody in, say, the intergalactic void would be slightly higher than three degrees. Anywhere less rarefied than the intergalactic void, the equilibrium temperature would be higher, depending on just how much stuff is bouncing off our imaginary blackbody, and how hard. That\'s where the idea of an ambient temperature comes from. But that\'s not the only meaningful notion of temperature we have. In fact, while it\'s the most useful notion of temperature in everyday life, it\'s really the least scientifically rigorous one.

If you stick a thermometer outside a spaceship, you are not measuring the temperature of space. You are measuring the temperature of the thermometer.

That\'s always true, regardless of where you stick your thermometer. That\'s what a thermometer is: It\'s a thing that reaches an approximation of equilibrium temperature in a usefully short time and that can somehow be measured to quantify its temperature. That\'s true whether you\'re talking about a bulb of alcohol with a graduated cylinder on it or a very precisely made thermocouple.

In the case of KSP, you\'re more than welcome to assume that every vessel has a very precisely made thermocouple sticking out into the airflow (or lack thereof, whichever), such that we can measure the temperature outside many times a second. That\'s what FlightIntegrator.getExternalTemperature() returns. Yes, in reality it\'s just giving you a synthetic number from the game\'s physics engine, but it works like it\'s a thermocouple sticking out into the airflow.

Space isn\'t hot or cold, because it isn\'t anything. It\'s void. If there is no matter, you can\'t measure the properties of that matter.

Temperature isn\'t a property of matter. It\'s a property of space. More precisely, entropy is a property of space —any defined volume has a defined entropy —and temperature is a measurement of entropy.

Because of this, the possibility of liquid water on the surface of a moon with no atmosphere is zero.

That\'s not why you don\'t have liquid water in a place with no atmosphere. You don\'t have liquid water in a place with no atmosphere because when the ambient pressure drops below the vapor pressure of water, the water ceases to be a liquid. That\'s true regardless of the temperature.

Water can only be liquid within a very narrow temperature range.

Water can be liquid within a practically boundless temperature range, if the ambient pressure is right. Pressure, temperature and state all go hand-in-hand.

[RayneCloud]

It should be getting the same amount of light as kerbin and the mun, and unless the surface reflects 80+% of the light hitting it, it should be roughly the same temperature range as the mun.

Anyone have an explanation for this?

Not really an issue, even in the slightest. It\'s out in deep space, and tiny as all get out. It\'s frozen, so there ya go.

[thorfinn]

Because of this, the possibility of liquid water on the surface of a moon with no atmosphere is zero.

not why you don\'t have liquid water in a place with no atmosphere. You don\'t have liquid water in a place with no atmosphere because when the ambient pressure drops below the vapor pressure of water, the water ceases to be a liquid. That\'s true regardless of the temperature.

Water can be liquid within a practically boundless temperature range, if the ambient pressure is right. Pressure, temperature and state all go hand-in-hand.

Well, now that\'s exaggerating a bit on the other side Above 374 °C, it\'s supercritical, so it\'s not really a 'liquid' nor a 'vapour' anymore. And below about -30 °C, you are bound to have some kind of ice.

Not really an issue, even in the slightest. It\'s out in deep space, and tiny as all get out.

Well, it\'s not in 'deep' space at all, it\'s at the orbit of Kerbin

[Bekiekutmoar]

In my opinion, the \'frozen lakes\' on Minmus are vast plains of sand and dust. There is a sand/rock texture on it ... !

[Rocketscience101]

I think of minmus as a comet. A very large comet that had been grabbed by kerbin. Like Kerbin, comets orbit a star, if kerbin were in the right position at the right time, a comet, which could become minmus, could be caught by its gravity, just like when we do a de orbit burn to get to either the mun or the minmus. As kerbins gravity field captured the minmus. Many of you might wonder, but comets have gasses shooting out of them, making those great tail shape. This is made by depresserising gasses, within the comet, that shoots out of holes in the comet like a rocket, producing, little to no thrust, but the comet may have lost its gas, and became just a giant snow ball to land on.

[Kryten]

At the temperatures and pressure that would be present at Kerbin\'s orbit, \'snow\' is itself a gas.

[Khrissetti]

I think of minmus as a comet. A very large comet that had been grabbed by kerbin. Like Kerbin, comets orbit a star, if kerbin were in the right position at the right time, a comet, which could become minmus, could be caught by its gravity, just like when we do a de orbit burn to get to either the mun or the minmus. As kerbins gravity field captured the minmus. Many of you might wonder, but comets have gasses shooting out of them, making those great tail shape. This is made by depresserising gasses, within the comet, that shoots out of holes in the comet like a rocket, producing, little to no thrust, but the comet may have lost its gas, and became just a giant snow ball to land on.

I was under the impression that it was sublimating ice from the surface, which would continue so long as it was in sufficient sunlight.

[duckunlimited2]

I notice that at night on Minmus you can see the stars and milky way, but they fade from view when the sun is out. Since in real life that would only happen if an atmosphere was scattering the sunlight to overwhelm the lesser lights, does that imply that Minmus has a considerable atmosphere? Or is it just an aspect of the game\'s lightning effects? I\'ve had a ship orbiting 4000-6000m for game-days, with no apparent slowing due to air resistence.

The same conditions apply on Mun, which I think is supposed to be a scaled-down version of our own Moon, and therefore would seem to be airless by intention. Then again, it\'s larger than Minmus, so if Minmus does have an atmo, why not Mun

It could be releasing its gases when kerbol warms the lit side enough to sublimate its icy surface, creating a psuedo-atmosphere on the lit side. The Convection currents (or solar waves, or whatever that\'s called) could be moving the gases to the dark side of minmus, then it would turn into ice again. from then on, the cycle continues.

Ima going to conduct some temperature data gathering on minmus in about a week. We\'ll see whats happening when the data tells its story.

[Khrissetti]

It isn\'t to do with gas or pseudo-atmosphere but simply the overwhelming light of Kerbol and the reflection from the surface. The Apollo landings had the same effect whereby the starlight was drowned out by the sun.

Interestingly, you didn\'t get this effect in v13, the stars shone regardless.

[Vanamonde]

Interestingly, you didn\'t get this effect in v13, the stars shone regardless.

Ah! That clarifies the thought in my own head. The point I was trying to get at is that since the game is a created thing, the makers could have had the stars out during the day or not, so what does it imply that they decided to hide the sky during day? Atmo or aesthetics?

[Randox]

That whole \'look through a pipe and see the stars\' is a myth. the atmosphere of Earth scatters the sunlight through the atmosphere, which makes it appear blue as well.

The inability to see stars during the day on Minmus is possibly similar to the reason you can\'t see the stars in the original Appollo landings, the light from the sun and reflected off the blinding surface of the Moon swamps the relatively small light from the stars.

I believe this works if you have access to a say 40ft deep drilled well that you can stand in the bottom of. The idea being that its narrow and tall enough that the refracted light can\'t reach your eyes at the bottom of the hole, so you only see the light sources that are in direct line of sight. Obviously would work a lot better when the sun is closer to the horizon.

Not sure if you can actually see stars doing this, but it is supposed to turn the sky black.

[Alchemist]

I believe this works if you have access to a say 40ft deep drilled well that you can stand in the bottom of. The idea being that its narrow and tall enough that the refracted light can\'t reach your eyes at the bottom of the hole, so you only see the light sources that are in direct line of sight. Obviously would work a lot better when the sun is closer to the horizon.

Not sure if you can actually see stars doing this, but it is supposed to turn the sky black.

It shouldn\'t change how blue is the sky, but it can reduce light that gets into your eye from other sources (including the rest of the blue sky) - therefore it increases sensitivity of your eye and allows to see some bright stars.

[VincentMcConnell]

/spoiler]

That\'s not the real photo, by the way. That has been edited...