The view is different for each of us, but this perspective unites us all.
From anywhere on Earth, the entire sky rotates a full 360° every 24 hours.
A skyward-pointed camera with the shutter left open will capture curved streaks: star trails.
From the International Space Station’s perspective, a far more spectacular view awaits.
https://www.youtube.com/watch?v=dG_0loA99uc
The ISS orbits so rapidly that it completes a revolution around Earth every 90 minutes.
Since 2010, ISS astronauts have had access to a “cupola,” granting direct, wide-field views of Earth.
It also gives the astronauts an opportunity to experiment with novel photography techniques.
Arguably, the best images come from Don Pettit, the first astronaut to attempt it.
By stacking a few dozen 30-second exposures together, he produced spectacular star-trails.
Down below, the Earth appears to move relative to the ISS, creating ground streaks.
Meanwhile, the stars streak not around the Earth’s axis, but around the ISS’s (arbitrary) axis of rotation.
The green and red layers above Earth’s atmosphere are airglow, visible everywhere.
The yellow streaks are caused by artificial lighting, while blue “dots” arise from lightning strikes.
Occasionally, a brilliant auroral display joins the show as well.
We’re all part of this one Earth, as captured from this unique vantage point.
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.
Ethan Siegel is the author of Beyond the Galaxy and Treknology. You can pre-order his third book, currently in development: the Encyclopaedia Cosmologica.