whiskysinger
whiskysinger t1_j1tatp4 wrote
Reply to comment by EdwardOfGreene in Meet the amateur astronomer who found a lost NASA satellite by jarvedttudd
A UK pint is 568ml A US pint is 473ml
The UK conversion rate of casual language to real pints is not as well understood, despite years of research.
"A swift half" = at least 2 pints "A couple of pints" = at least 6 pints + 1 kebab
whiskysinger t1_j3fzhrd wrote
Reply to comment by lith1x in My 1st ever star trail from space. More details in comments. by astro_pettit
Yes - it is exactly the same mechanism as the star trails taken from Earth's surface. Except the ISS is orbiting much quicker than the Earth is rotating. This is why the trails in this photo are so long for such a short exposure*.
Interestingly, the celestial pole is different on the iss than what we are used to on earth (Polaris in the northern hemisphere) because the orbital axis is not the same as Earth's axis of rotation, as demonstrated in the gif below.
https://gfycat.com/meagerscientificbengaltiger
*The ISS takes 90 minutes to orbit the earth. This means it is completing one trip around its orbital axis 16 times per earth day. The photo took 65 seconds of exposure. To capture star trails of this length on earth would take 16 x 65 seconds = 1040 seconds = 17m20s of exposure. (I think! Please correct me if I'm wrong)