Is 1d = 24h or 1d = 23h+56m then?
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A Solar day, 24hr, is the time between two sunsets. A Sidereal day, 23h 56m, is the time Earth spins around 360 deg relative to the relatively fixed stars surrounding us.
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Yeah, but what is MArs's rotation time in hours? 24h 32m I guess.
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Nah, all the times on that are sidereal, meaning they literally need to revolve 360 degrees. The problem with a Solar day is that when the planets move around the sun, the sun is slightly in a different place. This is exaggerated but shows it:pic.twitter.com/Mpry0TTZqg
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If 1d = 23h+56m (sideral earth day), then you should have answered "yes," because 1d+36m = 24h+32m. Otherwise, I just don't understand.
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Ohh, this is very subtle, I see what you mean now. I was using our own definition of day when I say "d" anywhere. So for Mars, it's 24h + 36m. The alternative for this would have been for me to quote everything as hours, but it wouldn't be helpful to show Mercury/Venus in hours
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Opinion. Consistent units should be chosen to allow meaningful comparisons: it would be more helpful to show everything in hours and minutes than to introduce possible misunderstandings such as this.
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All units are converted to those which regular people deal with. Mercury and Venus would mean people gettint out calculators. Having these periods be *instantly graspable* was important to this. Saying that though...I was 50/50 on saying hr+min for Mars!
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Would it be okay with you if I posted a downsampled animated gif version in our image library, credited to you of course, with a link to the mp4 version hosted on our Amazon S3 site?
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Hi Emily, absolutely! Let me know if you need different aspect ratios etc.

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Here's my gif attempt, got it to loop after to earth rotations.pic.twitter.com/TlCcSmDX7E
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*two earth rotations
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Ah nice. This is really crisp!
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Cheers! not bad for 256 colours! I scaled it to 960x536 and weighs in at 13mb.https://www.dropbox.com/s/db93jjttucq0xid/8planets_ODonoghue_Educators_960x536.gif?dl=0 …
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Sweet, thanks! Nabbing that!

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You're very welcome! And thank you, excellent holiday project!
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Very cool! Just as a bug report, at around 0:27-0:28, there's a few glitches in the video. It pixelates badly and the colours go wonky.pic.twitter.com/JKraL4XzXF
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I actually don't see this in the pre-uploaded (checked each frame) and uploaded versions, on my laptop or phone, hmm
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That's strange. I played it in VLC, going frame by frame. Here's frames 24, 25 and 26, of the 27th second of the video. Along with the colour change, note how the rotation arrow skips backward. Frame 25 seems to be the same as frame 18 of that second.pic.twitter.com/AYQn0Af4WO
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For the subsequent glitches (there's maybe 8 of them, total), it always skips back a number of frames. It never seems to be by the same amount, though. Looks like Frame 27 skips to Frame 21, and Frames 29 and 33 both skip back to Frame 23.
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I wonder if that's compression from downloading it? Do you see this glitch on Twitter itself? Here's a higher resolution version fyi:https://tinyurl.com/y85u2ev7
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Ah. There we go. The one in your tweet plays just fine. No glitches.
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As soon as I go to the dropbox page, and either play it there, or play the one I download from there, that's when the glitches show up.
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Hmm, that's odd! I downloaded it and looked at each frame from 36-40sec and it looks normal. It sounds like something complex to do with video codecs, I'm no expert though
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