I have no answer but I want to help the post gain attention by putting a comment in here.
I would be super interested in the answer as well, though again I have no idea what it might be or even what factors go in to the equation. I may be off in my assumption (and you may have already accounted for it) but I imagine the calculations for a satellite orbiting the body whose horizon is the subject must be different by at least one term from the calculations of governing a body orbiting the same mass as the horizon-owning-body
This scenario is hard to stomach too, because such large, lumpy gas clouds should fracture into stars before forming a black hole.
Seems to make sense that in the denser early universe that pressure wasn't quite enough to overcome just how much mass these early clouds had hanging around so close.
Not an expert but I imagine it’s the ocean depth. If the atmosphere above determines the temperature, and the ice at the surface acts as an insulator, the deeper parts of the ocean don’t get cold enough to freeze.
Saving you a click: Sun like stars turn into a red giant which is hard to live near and destroys nearby planets. After that red giants turn into white dwarfs which are possible to survive near but normally there aren’t any planets left to live on.
The article is about them discovering a jupiter size planet around a white dwarf
Thanks. If anybody is interested, I saved this article about said planet. It does, imho, a good job of going a bit deeper into the paper without beeing to technical (speaking from a lay persons perspective)
“Eventually, it was reported that the sprouted plants had died, that the potatoes failed to sprout, and that the fruit flies failed to hatch. The total run time for the experiment was nine days instead of the planned 100.”
An important addition to that may explain why: The lunar night approached -150° C and the experiment failed to keep the steady 24° C that it was supposed to maintain, so the plants died. I don’t think it was because growing plants on the moon is intrinsically impossible.
I also wonder how they expected 18 mL of water to last more than a few days anyway. Perhaps someone smarter than me can answer that.
2 week long nights will kill any plant, at least down to the roots. 2 week long days will kill most. Can't garden on moon. Not without grow lights. Maintaining temperature isn't enough.
I also wonder how they expected 18 mL of water to last more than a few days anyway. Perhaps someone smarter than me can answer that.
In any enclosed system the water circulates through the plant, evaporates into the air, possibly condenses on surfaces, then is drawn back into the plants again. There is no need to add water as long as there is enough tongo through the cycle.
This was basically a heated terrarium that did not stay warm enough.
Plants grow mostly by sucking water into their cells, so the water should soon end up stuck in the plants if everything else went right. I suppose they did count with it, but 18 ml of water is still suprizingly little.
The entire farm was about the size of an ice cube tray, and had a growing volume of about 2 cups. Terrariums in general would use about 6 tsps for a 2-cup terrarium; the Chinese experiment used about 3.5 tsps. I'm not sure why they used that amount of water; I would speculate (and it's only speculation) that the plants they choose didn't need more, or possibly the lower gravity on the moon meant that the water was generally more accessible to the plants.
(The lander will contain a box of various mementos. Since the contents of that box were collected in the middle of the cryptocurrency craze, various groups of course included various tokens representing their favorite coin, especially as “to the moon” was and is a meme representing the desired massive rise in value.)
if a length measurement yields 114.8 mm, using a ruler with the smallest interval between marks at 1 mm, the first three digits (1, 1, and 4, representing 114 mm) are certain and constitute significant figures.
Let’s assume they measured these 40 quintillion with a “ruler” which has a resolution of 1 quintillion. In that case, they could just as well say the number is 40.1539577 quintillion, or dream up any other combination of digits after the leading ‘40’ (like, for example “000,000,000…”). Because they don’t know.
But if they noted a non-zero string of digits, readers would wrongly assume their ruler has sufficient precision to measure these smaller digits.
So this notation conveys two insights:
We know the first digit(s): It’s 4. (and maybe 40, 400, …)
We don’t know the smaller digits, but we do know the magnitude.
So a non-round number would be suspicious, because it pretends to have precision which it most certainly cannot have.
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