A year's worth of gamma-ray sky observations has been transformed into a mesmerizing animation by NASA's Fermi Gamma-ray Space Telescope. The Large Area Telescope (LAT), which records the sky in gamma rays - the highest-energy form of light - aboard the spacecraft, captures the cosmic fireworks invisible to the naked eye.
You can watch the animation here.
Frenzied Activity
The animation showcases the frenzied activity in the gamma-ray sky between February 2022 and February 2023, represented by pulsing circles, which are a subset of more than 1,500 light curves collected by LAT over nearly 15 years in space.
The LAT data is now available in a continually updated interactive library, which was made possible by the work of an international team of astronomers. Astronomers studying galaxies have inspired the team to assemble the database, as they wanted to compare visible and gamma-ray light curves over long time scales.
"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," Daniel Kocevski, a repository co-author and an astrophysicist at NASA's Marshall Space Flight Center, said in a press release statement.
Blazars, central regions of galaxies hosting active supermassive black holes, produce powerful particle jets pointed almost directly at Earth.
According to NASA, more than 90% of the sources in the dataset are blazars, which are important sources for multimessenger astronomy, where scientists use combinations of light, particles, and space-time ripples to study the cosmos.
Ground-based observatories such as the National Science Foundation's IceCube Neutrino Observatory in Antarctica can sometimes identify high-energy particles generated from these jets.
Each frame of the animation represents three days' worth of observations. The magenta circle around each object expands with brightness and shrinks as it dims.
The Milky Way galaxy's central plane, a rich source of gamma rays, is visible as a band of reddish-orange in the center of the sky. Lighter colors there indicate a brighter glow. The yellow circle shows the Sun's apparent annual trajectory across the sky.
400 Computer Years
A computer cluster at the SLAC National Accelerator Laboratory in Menlo Park, California, needed almost 400 computer years of processing time to process the entire inventory.
The LAT, the primary instrument of Fermi, searches the whole sky every three hours for gamma rays with energies ranging from 20 million to more than 300 billion electron volts.
The Fermi Gamma-ray Space Telescope is a combination between astrophysics and particle physics, and it is under the direction of Goddard.
The spacecraft was developed by the US Department of Energy in collaboration with partners from academic institutions in France, Germany, Italy, Japan, Sweden, and the United States. These governments also provided significant financing for the project.
With the historical light curve database now available, the scientific community anticipates new multimessenger insights into past events.