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1. Wonder of Science (wonderofscience@mastodon.social)'s status on Friday, 31-Jan-2025 07:31:54 JST Wonder of Science

   Time-lapse of astronaut Chris Cassidy working outside the International Space Station as it orbits the Earth.

   Video credit: NASA Johnson

   • David Chisnall (*Now with 50% more sarcasm!*) (david_chisnall@infosec.exchange)'s status on Friday, 31-Jan-2025 19:16:49 JST David Chisnall (*Now with 50% more sarcasm!*)

     in reply to

     @wonderofscience What’s caring the shadows with soft edges? Most shadows in space have hard edges (which most SciFi CGI gets wrong) because there’s no air to diffuse the light. You can see that with the shadows the astronaut casts on the side of the station. But the ones from the station have soft edges, which I would expect to happen only if they are cast by something translucent. Maybe the edges of a solar panel?

   • Wonder of Science (wonderofscience@mastodon.social)'s status on Friday, 31-Jan-2025 19:52:20 JST Wonder of Science

     in reply to

     The edges of shadows cast by the Sun appear soft because it is not a point source. This softness, called the penumbra, occurs where only part of a light source is obscured. As the shadow extends farther, the penumbra widens, making the transition between light and dark more gradual, which is why the astronauts' shadows appear sharper (near), but the solar array shadows appear soft (far).
     https://kids.britannica.com/students/assembly/view/229835

   • Wonder of Science (wonderofscience@mastodon.social)'s status on Friday, 31-Jan-2025 20:51:41 JST Wonder of Science

     in reply to

     I went looking for another good example of soft shadows in space and found this photo of the likely culprit from the video, Canadarm, photobombing with a fuzzy shadow.
     https://www.flickr.com/photos/nasa2explore/52580489065/