Fermi Gamma-ray Space Telescope tagged posts

Nearby Pulsar’s Gamma-Ray ‘Halo’ linked to Antimatter Puzzle

a photon "squiggle" collides with an electron "dot"; there's a flash and the photon (now a higher-energy gamma ray) shoots away
Particles traveling near light speed can interact with starlight and boost it to gamma-ray energies. This animation shows the process, known as inverse Compton scattering. When light ranging from microwave to ultraviolet wavelengths collides with a fast-moving particle, the interaction boosts it to gamma rays, the most energetic form of light.
Credits: NASA’s Goddard Space Flight Center

NASA’s Fermi Gamma-ray Space Telescope has discovered a faint but sprawling glow of high-energy light around a nearby pulsar. If visible to the human eye, this gamma-ray “halo” would appear about 40 times bigger in the sky than a full Moon. This structure may provide the solution to a long-standing mystery about the amount of antimatter in our neighborhood.

“Our analysis suggests that this same puls...

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All of the Starlight ever produced by the Observable Universe Measured

This map of the entire sky shows the location of 739 blazars used in the Fermi Gamma-ray Space Telescope’s measurement of the extragalactic background light (EBL). The background shows the sky as it appears in gamma rays with energies above 10 billion electron volts, constructed from nine years of observations by Fermi’s Large Area Telescope. The plane of our Milky Way galaxy runs along the middle of the plot.
Credit: NASA/DOE/Fermi LAT Collaboration

The team’s measurement, collected from Fermi data, has never been done before. From their laboratories on a rocky planet dwarfed by the vastness of space, Clemson University scientists have managed to measure all of the starlight ever produced throughout the history of the observable universe.

Astrophysicists believe that our universe, whic...

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NASA’s Fermi discovers the most Extreme Blazars yet

Black-hole-powered galaxies called blazars are the most common sources detected by NASA's Fermi. As matter falls toward the supermassive black hole at the galaxy's center, some of it is accelerated outward at nearly the speed of light along jets pointed in opposite directions. When one of the jets happens to be aimed in the direction of Earth, as illustrated here, the galaxy appears especially bright and is classified as a blazar. Credit: M. Weiss/CfA

Black-hole-powered galaxies called blazars are the most common sources detected by NASA’s Fermi. As matter falls toward the supermassive black hole at the galaxy’s center, some of it is accelerated outward at nearly the speed of light along jets pointed in opposite directions. When one of the jets happens to be aimed in the direction of Earth, as illustrated here, the galaxy appears especially bright and is classified as a blazar. Credit: M. Weiss/CfA

NASA’s Fermi Gamma-ray Space Telescope has identified the farthest gamma-ray blazars, a type of galaxy whose intense emissions are powered by supersized black holes. Light from the most distant object began its journey to us when the universe was 1.4 billion years old, or nearly 10% of its present age...

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NASA’s Fermi Gamma-ray Space Telescope Sharpens high-energy Vision

This image, constructed from more than six years of observations by NASA's Fermi Gamma-ray Space Telescope, is the first to show how the entire sky appears at energies between 50 billion (GeV) and 2 trillion electron volts (TeV). For comparison, the energy of visible light falls between about 2 and 3 electron volts. A diffuse glow fills the sky and is brightest in the middle of the map, along the central plane of our galaxy. The famous Fermi Bubbles, first detected in 2010, appear as red extensions north and south of the galactic center and are much more pronounced at these energies. Discrete gamma-ray sources include pulsar wind nebulae and supernova remnants within our galaxy, as well as distant galaxies called blazars powered by supermassive black holes. Labels show the highest-energy sources, all located within our galaxy and emitting gamma rays exceeding 1 TeV. Credit: NASA/DOE/Fermi LAT Collaboration

This image, constructed from more than six years of observations by NASA’s Fermi Gamma-ray Space Telescope, is the first to show how the entire sky appears at energies between 50 billion (GeV) and 2 trillion electron volts (TeV). For comparison, the energy of visible light falls between about 2 and 3 electron volts. A diffuse glow fills the sky and is brightest in the middle of the map, along the central plane of our galaxy. The famous Fermi Bubbles, first detected in 2010, appear as red extensions north and south of the galactic center and are much more pronounced at these energies. Discrete gamma-ray sources include pulsar wind nebulae and supernova remnants within our galaxy, as well as distant galaxies called blazars powered by supermassive black holes...

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