Oleg Zabluda's blog
Monday, July 30, 2012
 
ISS Summer Solstice timelapse, showing that the Sun doesn't set (Polar Day).
ISS Summer Solstice timelapse, showing that the Sun doesn't set (Polar Day).

ISS orbital inclination is 51.6 deg, which is short of Arctic Circle (66.6 deg) by 66.6-51.6=15 degrees, which must be due to ISS 330-400 km altitude (H), allowing astronauts to peek below the horizon by 

arccos(6371 / (6371 + H)) = 18-20 deg.

The video was shot not during Summer Solstice (June 20), but on June 6, when the Sun was 1 degree lower.

In the video, the Sun is making the circle with radius of 15 degrees.

Note also that (unlike the "bad astronomy" sketch), this video was shot from the Southern hemisphere (due to the direction of Sun's movement). ISS orbit precesses by ~5 degrees per day.

http://blogs.discovermagazine.com/badastronomy/2012/07/25/space-station-solstice/

Sunrise and Sunset around Summer Solstice
http://www.youtube.com/watch?v=Kb84FkTuHuQ

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