Giant Tidal Waves are Crashing Onto the Surface of an Enormous Star

By Brian Koberlein - August 12, 2023 01:39 PM UTC | Stars
Although the surface of a star seems quite different from the ocean, the underlying effect of gravity can create similar conditions. One type of star is known as a "heartbeat star," where a binary system interacts with one another, generating enormous stellar tides from their mutual gravity. In one extreme system, the gravitational effect is 200 times larger than any heartbeat star seen before. An enormous wave is generated across the star as its binary companion approaches. Like ocean waves, these waves break, crashing down onto the star's surface.
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Evidence for Modified Gravity Found in the Motions of Binary Stars

By Brian Koberlein - August 11, 2023 02:09 PM UTC | Physics
There are two leading explanations for dark matter, massive particles that don't interact with regular matter apart from gravity and a subtle difference in how gravity behaves at large distances. Astronomers have studied the interactions of over 20,000 binary stars with wide orbits cataloged in Gaia data. They found that orbital accelerations of the stars match the predictions made by modified Newtonian gravity and provide compelling evidence for the MOND hypothesis over the dark matter being a particle.
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Astronomers Search for Dark Matter Annihilation at the Center of the Earth

By Brian Koberlein - August 10, 2023 12:52 PM UTC | Physics
If dark matter is made of heavy particles, they could become captured by the gravitational field of massive objects like stars or planets. Constrained in a small area, these particles could crash into one another and annihilate with radiation. Astronomers have searched through 10 years of data captured by the IceCube Neutrino Observatory at the South Pole for any evidence of this dark matter annihilation. Although they didn't detect any evidence, the next generation IceCube Update will significantly improve the search.
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Could This Supermassive Black Hole Only Have Formed by Direct Collapse?

By Brian Koberlein - August 09, 2023 01:15 PM UTC | Black Holes
One of the outstanding mysteries in astronomy is how supermassive black holes gained so much mass so early in the Universe. The traditional theory is that stellar mass black holes merge, building up to supermassive levels. Another theory suggests that supermassive black holes might have collapsed directly out of enormous clouds of gas and dust. Astronomers using JWST and Chandra think they've discovered a black hole that's too massive, too early, and could only have formed from direct collapse.
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