A year in the gamma ray sky! Small specks are mainly supermassive black holes in distant galaxies. Big short-lived blips are gamma-ray bursts... also from distant galaxies.
I think I recognize some of the persistent bright spots near the Galactic plane, like Cygnus and Vela. Others are mysterious to me. Let's compare a map of the X-ray sky, where these objects are named!
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Here's the X-ray sky for comparison. Now you can clearly see the black hole, neutron star and supernova remnant in Cygnus! Also the supernova remnant in Vela - a pulsar, to be precise.
It would be fun to see the two maps overlaid.
The new animation of the gamma-ray sky, made by Daniel Kocevski and his team, is based on data from NASA’s Fermi satellite from February 2022 to February 2023:
The data is available at this continually updated interactive library:
https://fermi.gsfc.nasa.gov/ssc/data/access/lat/LightCurveRepository/index.html
Here's an open-access paper about all this:
https://iopscience.iop.org/article/10.3847/1538-4365/acbb6a
“We were inspired to put this database together by astronomers who study galaxies and wanted to compare visible and gamma-ray light curves over long time scales,” said Daniel Kocevski, a repository co-author and an astrophysicist at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “We were getting requests to process one object at a time. Now the scientific community has access to all the analyzed data for the whole catalog.”
I bumped into the animation on Ethan Siegel's column explaining why the Moon is brighter than the Sun in gamma rays:
https://bigthink.com/starts-with-a-bang/surprise-moon-outshines-sun/
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Cosmic fireworks, invisible to our eyes, fill the night sky. We can get a glimpse of this elusive light show thanks to the Large Area Telescope (LAT) aboard NASA’s Fermi Gamma-ray Space Telescope, which observes the sky in gamma rays, the highest-energy form of light.
John Carlos Baez
decitect