McGordan, Mars is cold, it only gets to 32 d F at the equator in the daytime.
Mars is cold, but Mars is also mostly rocky and has sufficient gravity to maintain some semblance of an atmosphere. Any ice that sublimates can eventually freeze and return the surface as ice again. With smaller asteroids, not so.
Astorids are below freezing.
Kinda sorta. Fill a cooler with ice. The ice in that cooler is now at exactly the freezing point of water, but nothing is cooling it further - it's just the cooler keeping out the energy that is keeping it frozen. Go back 12 hours later. You'll have an ice/water slush. Now, if you stick a therometer in that, it's STILL at the freezing point, but it can't maintain that because cold really isn't a "thing". It's more just the absence of heat. As more heat is added to the system, more and more of the ice will melt, until you have none. Until all of it is melted though, a thermometer will always read it as freezing.
A similar thing happens with colder bodies in the inner system. Under direct sunlight, the ice will slowly melt, even though the object itself is freezing. Things too close, melt completely away. In this case the ice tends to sublimate - go from a solid directly into a gas. When it does that, pressure from solar wind will push the gas outwards. Unless the gravity of the object is high enough to hold onto that gas, it gets blown off. That's why comets leave tails
.
I saw on Nasaspaceflight.com that they have been talking about mining astorids.
Indeed, it's something that will likely happen. For minerals and metals though, not water.
One astorid, I think Ceres is nothing but ice. It is larger than the moon. So, yes there are probably ice balls or rocks in the astroid belt.
Sorry, but nope. Ceres is easily the largest asteroid in the belt, but the moon is 3.5x the diameter and 77 times as massive. Now, by virtue of it's relatively high mass for an asteroid (Ceres has almost one third of the mass of the entire belt), it's managed to hang onto more water ice than most, but like most of the planets we're talking mostly slushy rock and mud, not solid water like the outer Kuiper Belt objects. Tell tale sign is the density. Water as an ice has a density of roughly 0.9 g/cm^3. The mean density of Ceres is 2.1 g/cm^3. Well over twice that of water. Compare that with most comets coming in from the outer system, which tend to be between 0.5 and 1 g/cm^3 (being mostly water and gases).
Here is a good set of photographs in scale to show the size differences between the Earth, Moon, and Ceres.
We don't yet know all the minerals mars may have, but I think they have found aluminum as well as of course iron. I think, if the world survives, and we survive beyond the current socialism, we will be mining the moon and Mars, and since Mars does have water, it could provide crops grown in greenhouses.
Mining the asteroids for minerals and ore is pretty likely. For water, the economics just isn't there. You're still going to have to seperate it from slush, and if you're going to do that, virtually all the inner bodies where you'd want to use it have it already anyways, and without the need for transport (and Earth certainly won't need it - desalinization will always come out ahead in cost vs transporting through space). Crops run into a similar problem, with crops grown on Mars likely only being useful for people living on Mars. You just have to think of it from a point of economics: the cost to transport something between planets is ENORMOUS. Huge. Unimaginably high. For a renewable item like produce, you will never reach a break even point. Put it this way, one of the cheapest methods of getting into orbit currently is the Russian Proton rockets. The current cost just to get TO ORBIT - not from one planet to another, but just from the surface into space - is $4300 per kg. So 1 pound of corn would cost $9,460 to get into space - using one of the cheapest methods we know (some other rockets cost 10x as much). Combine that with the fact that Mars is twice as far away from the Sun as Earth, and hence receives half the solar energy, you just don't have a good recipe for an export market in agriculture. The only reason to grow crops on Mars would be for colonists there, to avoid the reverse high cost of bringing food over from Earth.
Unless there is water near the moons poles, it will require water being transported there for human consumption. That is why the moon will probably only be used for mining.
NASA has already shown via the LCROSS mission that the moon does indeed have water. Given it's relative proximity, it's also much easier to supply it vs a Martian colony (ie, in a pinch if something went wrong or food ran low, we can have cargo to the moon in 3-4 days - getting something to Mars takes a few months minimum). Combine that with the much higher amount of solar energy reaching the moon vs Mars, and I think the moon is much more likely for colonization (at least earlier - I think in time both with be colonized).
The LaGrange points at L1 or L2 will be where they will want to build a large space station as a jump off to Mars or anywhere else. The L points are the area where the Earth and Moons gravity cancel each other out. Easier to break away and go to Mars or the astroids from there. With solar or nuclear power, Mars will be inhabited.
That one I agree with, but I think we'll be on the Moon much earlier, as I said just due to proximity. It will be a LONG time before any of these colonies would be completely self-sufficient, and the moon is just an easier maintenance proposition. Its quicker to get to, the gravity is lower (so return trips take less energy), it gets more solar energy, etc. Sure it has no atmosphere, but Mars' atmosphere is relatively thin and not at all breathable, so you're going to have to have air-tight structures with an artificial atmosphere in either location anyways.
