Originally published at: https://boingboing.net/2020/01/10/excellent-animation-comparing.html
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That was really cool. I found the rotational rate of the Gas Giants to be a real surprise. The Speed of Light one is mind boggling.
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And how fast would they have to “spin up” Ceres in order to get centrifugal artificial 1/3 gravity as in The Expanse?
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Short answer: so fast the asteroid would likely fly apart.
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Note how similar the rotation of Earth and Mars are. A Martian day is 24 hours 39 minutes and 40 seconds. This led to a great concept in Kim Stanley Robinson’s Red Mars trilogy where the Martian settlers used standard Earth time with a day consisting of 24 60-minute hours, but all clocks would stop for 39 minutes and 40 seconds between midnight and 12:01am. This period was known as the “timeslip” and was seen by young Martians as a period “outside time” during which they could do impulsive things without worrying about consequences.
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This period was known as the “timeslip” and was seen by young Martians as a period “outside time” during which they could do impulsive things without worrying about consequences.
So, Marsspringa?
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First: Someone needs to make looping versions of these videos that last for at least several minutes, these are way too short!
Second: It’s interesting how close Earth and Mars are to one another.
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I would like to save these to a playlist but apparently this is some new class of content I didn’t realize is directed at kids and you are not allowed to even save the video for some stupid reason.
I actually find this useful for designing a functional realistic orrery. Any astrophysicists in the house that can tell me where to find more exact values of theta angle for rotation obliqity and time of sideral day?
I’ve seriously wanted to make a highly accurate functional mechanical orrery for a long time
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Yeah, that was my immediate impression. Big celestial objects are spheres because they are not strong enough to maintain any other shape against the force of their own gravity. So if you spun them they would slowly become more and more oblate until pieces started flying off. So I was figuring that you could bore a tunnel through the equator (really anywhere) and then place your habitat inside the tunnel and spin it. Like an endless train. But then of course you can eliminate the tunnel and make a much smaller ring habitat spinning on the surface. With the floor at the tilt, you could have full gravity on the moon, by adding the centrifugal force to natural gravity.
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https://ssd.jpl.nasa.gov/horizons.cgi
Web interface is a little clunky but will get you what you need.
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Hey thanks!
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