Why the Milky Way’s Dark Heart Might Be Shaped Like a Box

Simulated Milky Way with excess energy at the center. Credit - AIP / A. Khalatyan

Back in 2009, astronomers using the Fermi Gamma-ray Space Telescope noticed that there was a lot more gamma-ray light coming from the center of the Milky Way than might otherwise be expected given the objects there. Since then, two theories have appeared to explain this Galactic Center Excess (GCE) as it’s become known. One theory posits that the extra gamma rays are created by thousands of unseen milli-second pulsars (MSPs) in the Galactic center, while the other suggests that dark matter annihilating itself could also be the source. A new paper from Moortis Muru and hisco-authors at the Leibniz Institute for Astrophysics Potsdam (AIP) hasn’t necessarily solved the conundrum, but does level the playing field between the two theories again.

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Researchers Match Up 12 Meteorites with the Near-Earth Asteroids They Came From

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In our neighborhood of the Milky Way, we see a region surrounding the solar system that is far less dense than average. But that space, that cavity, is a very irregular, elongated shape. What little material is left inside of this cavity is insanely hot, as it has a temperature of around a million Kelvin. from Universe Today https://ift.tt/KvVDeiC via IFTTT

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