NASA’s Fermi captures a dynamic gamma-ray sky in a new animation

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 monitors the sky in gamma rays, the highest-energy form of light.

This animation shows the frantic activity of the gamma-ray sky during a year of observations from February 2022 to February 2023. The pulsars are just a subset of more than 1,500 light curves — records of how sources change in brightness over time — collected by LAT over 15 years in the space.

Thanks to the work of an international team of astronomers, this data is now publicly available on file An interactive library that is constantly updated. A paper about the repository was published March 15, 2023, in Astrophysical Journal supplement series.

“We were inspired to put this database together by astronomers who study galaxies and wanted to compare visible-light and gamma-ray curves over long time scales,” said Daniel Koszewski, repository co-author and astrophysicist at NASA’s Marshall Space Flight Center. Huntsville, Alabama. “We were getting requests to process one object at a time. Now scientific community Has access to all analyzed data for the entire catalog. ”

More than 90% of the sources in the dataset are Blazars, which are central regions of galaxies that host active supermassive black holes that produce powerful jets of particles directed almost directly at Earth. Earth-based observatories, such as the National Science Foundation’s IceCube neutrino observatory in Antarctica, can sometimes detect high energy particles produced on these aircraft. Blazars are important sources for multimedia astronomy, where scientists use ensembles of light, particles, and space-time ripples to study the universe.

“In 2018, astronomers announced the joint detection of a gamma ray and a high-energy particle called a Blazar neutrino for the first time, thanks to Fermi LAT and IceCube,” said Michela Nigro, an astrophysicist at the university. in Maryland, Baltimore County and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Having a database of historical light curves can lead to new, multi-message insights about past events.”

In the animation, each frame represents three days of observations. A purple circle for each sprite grows as it brightens and shrinks as it dims. Some things fluctuate throughout the year. The reddish-orange band that runs across the middle of the sky is the central plane of our Milky Way, and it is stationary Gamma rays project. Light colors indicate a brighter glow. The yellow circle shows the apparent annual path of the Sun across the sky.

Processing the full catalog required about three months, or more than 400 years of computer processing time spread across 1,000 nodes on a computer cluster housed at the SLAC National Accelerator Laboratory in Menlo Park, California.

LAT, Fermi’s primary instrument, scans the entire sky every three hours. explore gamma rays With energies ranging from 20 million to more than 300 billion electron volts. For comparison, the energy of visible light is mostly in the range of 2 to 3 electronvolts.

The Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership managed by Goddard. Fermi was developed in collaboration with the US Department of Energy, with significant contributions from Academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States.