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Cake day: June 24th, 2023

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  • A few reasons for that to my lay-person brain: firstly time zones would be wonky on other planets, the moon especially. Mars would be simplest because it’s only 37 minutes faster. But every planet would have different time zones. But time zones on planets or the moon are only relevant to intra-planet communications. Mars to Earth, even without the time delay, is going to have completely different times. Half an hour drift will make syncing times between planets more important than whatever time zone you are in since you’ll effectively need to adjust time zones every other day. So we’ll have to sync times between planets or have a UTC for each body that gets adjusted.

    But that’s not actually what NASA is proposing. For something as close and earth-dependent as the Moon, they’ll just use Earth times until there’s a significant colony up there. What NASA is talking about deals with relativity: experiencing more or less gravity changes how much time you perceive compared to people in different gravities. I.e. people on earth, people on the moon, and people in deep space experience time at different rates. 1 Second for space might be 0.8 seconds of time on a planet. So NASA wants clocks that physically tick faster than Earth to an amount of 0.000058 seconds per day. Which…isn’t a lot for a humans. Hundreds of thousands years just to equal a second. But it is a lot of very precise computers and instruments we use to measure long distances and speed.









  • No, I’m not.

    A Super-Earth is a type of exoplanet with a mass higher than Earth’s, but substantially below those of the Solar System’s ice giants, Uranus and Neptune, which are 14.5 and 17 times Earth’s, respectively.[1] The term “super-Earth” refers only to the mass of the planet, and so does not imply anything about the surface conditions or habitability.

    But regardless, a planet larger than earth but of a low enough density to be feasible would be unfeasible for other reasons. Namely we require a magnetosphere to survive on the surface and for atmospheres we can breath to exist. For that the planet likely needs an iron core, or another ferrous metal core. I guess there could be ways of generating a magnetosphere without a metal core, but I don’t think scientists have figured out how that could work yet. Seeing as Iron is the end state of fission/fusion and is quite common in the universe, the majority of planets that have a viable magnetosphere probably uses this method.

    That being said, the majority of the earth’s mass is the mantle, molten rock. It’s very unlikely suitable planets are made up of significantly less dense material than rock. And even without the core we’d replace the iron with rock and lower the overall mass by maaaaybe 20%. Still too massive to likely facilitate current rocket tech.