Fermi's 14-Year Time-Lapse of the Gamma-Ray Sky: Orthographic Projection

The entire gamma-ray sky is shown as two circular views centered on the north (left) and south poles of our Milky Way galaxy in this 14-year time-lapse of the gamma-ray sky. The central plane of our galaxy wraps around the edges of both circles, suppressing its glow and improving the view of black-hole-powered galaxies in the distant universe. Their gamma rays come from jets produced by supermassive black holes in distant galaxies that point almost directly toward Earth, which enhances their brightness and variability. Over a few days, these galaxies can erupt to become some of the brighest objects in the gamma-ray sky and then fade to obscurity. A moving source, our Sun, can be seen arcing up and down the circles as it appears to move through the sky, a reflection of Earth’s annual orbital motion. Watch for strong flares that occasionally brighten the Sun. In these maps, brighter colors indicate greater numbers of gamma rays detected by Fermi’s Large Area Telescope from Aug. 10, 2008, to Aug. 2, 2022.

Music credit: "Expanding Shell" written and produced by Lars Leonhard.

Credit: NASA’s Goddard Space Flight Center and NASA/DOE/LAT Collaboration
Producer: Scott Wiessinger (Rothe Ares Joint Venture)
Science writer: Francis Reddy (University of Maryland College Park)
Visualizer: Seth Digel (SLAC National Accelerator Laboratory)
Narrator: Judith Racusin (NASA/GSFC)
Scientist: Judith Racusin (NASA/GSFC)