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What of the lack of atmosphere and lack of active mantle/core? Solar energy has little chance of staying within the system.
Isn't surface temperature a good proxy value of the amount of energy inside the system?
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The book(s) acknowledges it's made of ice. You can't drink your entire habitat.
All the water on Earth was drunk at some stage wasn't it?
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I always wondered why we are overly focused on the conditions that created life on earth. Arguably it makes sense to see similar conditions lead to life. But do we really know enough to assume that's only way?
water and carbon a both uniquely suited to self assembling complex stuff, so its bot crazy to assume those are likely involved
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Isn't surface temperature a good proxy value of the amount of energy inside the system?
Well not necessarily. The Martian equator can get as hot as 18C. It doesn't retain the heat (due to no atmosphere) and it gets cold like even a few centimeters off of the surface.
Is this actually H2O water? I read the article but I am still unclear. I am often excited to hear that water was discovered on some planet or moon but its always a disappointment to learn that its liquid methane or some other liquid that is not actually H2O water.
There goes the water rationing narrative in The Expanse...
In addition the spinning up of Ceres is often mentioned as one the of many engineering feats attributed to Tycho.
EDIT: For scientific context to my statement H2O can be turned into really good propellant. Two of Blue Origin's engines run on Liquid Hydrogen and Liquid Oxygen for example.
There goes the water rationing narrative in The Expanse...
The title says "water" but the article says "brine". Don't count on it.
Ceres is one of the more interesting candidates for life in our solar system. Ceres is in the habitable zone for our solar system (although just barely), it's surface temperature is -30 F (eq. to winter in Greenland), and it's detected that the water on the surface is 20% carbon by mass (though that can mean a lot of things).
I always wondered why we are overly focused on the conditions that created life on earth. Arguably it makes sense to see similar conditions lead to life. But do we really know enough to assume that's only way?
Imagine a universe of only helium. No valence electrons would be readily available, so chances are you are not going to see helium molecules. Lithium, sure, as a metal. Continue examining various smaller (and more plentiful elements). Fluorine? Well, only one slot available, so you can make molecules with two atoms, but no chains. If you have two slots open, you can make a chain, but little else. Although try making a chain of oxygen -- even the three-link ozone is not particularly stable. Carbon can have four different bonds going at once, which is pretty crazy, and so you want something with three or four slots available.
But then you say, well, silicon could have four. And it could ... but for the fact that it is so huge by comparison to carbon (that whole other "electron shell") that it rarely has analogues to organic (carbon-based) compounds. Also, it doesn't like to do much until you get it fairly hot. So you climb back up a row and it looks like carbon, nitrogen, boron ... those are going to do your heavy lifting when you need multiple bonds, with hydrogen, oxygen, and the halogens or alkali metals somewhere on the outside. Hence carbon chauvinism. Carbon is something like the fourth most common element in the universe after all.
Then you start talking about solvents -- all of this stuff has to slosh around in something after all, your chemistry experiments take place in liquids -- and the field is a bit wider but dang, water has some crazy properties that make it quite a catch when it comes to solvents.
You've got temperature ranges: down in the single digits of Kelvin you're not going to have much chemistry happening, and up in the thousands of Kelvins even iron boils and then again, no more structure.
Once you start looking for these various "sweet spots" it all comes down to finding a place where you can have liquids (your solvent), solids (for structure), and gases (even if they are dissolved in liquids). Combine that with the more common elements (especially those that are friendly to complex chemistry) and you have something not entirely un-Earthlike.
There's tons of Wikipedia articles on it, but ... the restrictions of chemistry are the bulk of the culprit, I'm afraid.
spaceX when? 2048?
Somewhat related I saw it’s going to take NASA’s new Perseverance rover about 7 months to get to Mars and it’s traveling at something like 25,000 MPH. Since NASA had to take the planetary orbits and launch timing, etc. into account I’m assuming that’s the fastest ideal velocity for the rover but not necessarily the fastest possible. So I guess my question is, given that Ceres is so much further away than Mars, what’s…
Ceres is one of the more interesting candidates for life in our solar system. Ceres is in the habitable zone for our solar system (although just barely), it's surface temperature is -30 F (eq. to winter in Greenland), and it's detected that the water on the surface is 20% carbon by mass (though that can mean a lot of things).
I had to stand around waiting for a bus in 0 F for a few years of my life. Did not detect any life around that bus stop.