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Incredible New Gif Shows Cosmic 'Snow' On the Surface of a Comet (gizmodo.com)
Press2ToContinue shares a report from Gizmodo: What you're looking at is the surface of the comet 67p/Churyumov-Gerasimenko, which is orbited by the European Space Agency's Rosetta probe. The photo comes from Rosetta's OSIRIS, or Optical, Spectroscopic, and Infrared Remote Imaging System. The raw data was collected on June 1, 2016, and posted publicly on March 22 of this year. Twitter user landru79 processed the gif from this data release and shared it yesterday. In the foreground is the comet's surface (still several kilometers away from the probe), and three kinds of specks. The stars in the background belong to the constellation Canis Major, according to ESA senior advisor Mark McCaughrean. Some of the foreground stuff could be streaks from high-energy particles striking the cameraâ"it's a charge-coupled device (CCD), so even invisible particles can leave streaks in the results. And some could be dust from the comet itself.
Seems to be a little different. It's a 25 minute video that has been compressed in that GIF, so the effect is 'dramatized'. https://www.livescience.com/62... According to that report, the GIF, impressive as it is, is somewhat misleading.
Because the ESA is using 1960's film cameras?
You do see stars in Apollo photos. Just not when the camera is set to properly expose the sunlit lunar surface, which causes the stars to be vastly underexposed. Looking at the data for one of the images, it's a 12.5 second exposure. The scene is indirectly illuminated, you can see what appears to be an overexposed, sunlit highlight in the last frame of the animation.
The "falling" stuff is the starfield, they're all moving in unison. Read the comments at the original source - the images capture NGC2362 (Mag 4.1) and MGC2354 (Mag 6.1).
The stuff moving in semi-random directions (but mostly toward the upper left, it appears) is the "snow." That includes the streaks. In order for a cosmic ray to produce a streak, it would have to be traveling along the plane of the image sensor (or strong enough to effect an entire sensor row/column).
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