Recent comments in /f/space

sight19 t1_jdx0z40 wrote

For structure to form, you need to compress gas in a small volume. As gas is compressed, it's temperature increases and so do the random motions of the theoreticized WIMPs. That means that at a certain point, the gas cloud stops collapsing (this is also called 'virialization'). The only way to collapse further is if the gas cloud would leak out temperature somehow, and that can only happen via radiation. And dark matter can't radiate, so it can't cool further

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HeebieMcJeeberson t1_jdx0byy wrote

For one thing, perfect smoothness doesn't eliminate friction - there's also electrostatic attraction between molecules. Eventually the planet rotating under the water would coax it to move.

But moreover, the atmosphere would be screaming by overhead since it does rotate with the Earth. The atmosphere is chaotic, with zones of different pressures which press down on bodies of water unevenly, creating irregularities that the sideways wind can act on to create waves. This is how wind stirs up waves on calm, smooth lakes and such.

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StrangeTangerine1525 t1_jdwzw75 wrote

Yes but planets can lose gas to space via thermal escape, at very high rates depending on the temperature. There is also photochemical reactions caused by UV rays that can also drive atmospheric escape, so this planet could have a strong magnetic field and still have no atmosphere, especially if it is this close to its host star, a relatively active red dwarf at that.

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lezboyd t1_jdwwja8 wrote

Honestly, didn't read the article, it was a bit too long, but to further your argument, a Dyson sphere doesn't have to be a solid sphere encapsulating the star. One can theoretically put a swarm/lattice of 'dyson satellites' in orbit around the sun to achieve the same effect. What holds back the concept of a Dyson sphere as a valid energy source is not our satellite building tech or mining abilities, but that we don't yet know how to transmit this energy that's generated in Space onto Earth without frying it.

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Half-Borg t1_jdwwgp3 wrote

  1. Expansion is not constant. It has changed a lot between the big bang and now.
  2. Expansion depends on the amount of space there is, more space equals more expansion
  3. This is called the big rip. I'm not certain what the current state of research is regarding that. But it won't happen for many billions of years.
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EarthSolar t1_jdwuwab wrote

The idea of high altitude haze is for the haze to be in a zone where the atmospheric pressure is too low to effectively transport heat from dayside to nightside, and thus causing it to look like airless planet. That said the haze itself might move and jeopardize this, but I figured it's better to ask.

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PhoenixReborn t1_jdwsr9l wrote

Would that be consistent with the thermal measurements? Sounds like there isn't as much heat exchange between the day and night sides of the planet as there would be with an atmosphere.

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