Misaligned Binary Star Systems are Rogue Planet Factories

By Brian Koberlein - October 28, 2023 12:19 PM UTC | Stars
Astronomers are discovering that free-floating, rogue planets are common in the Milky Way. Hundreds were recently found in the Orion Nebula. Discovering the mechanism for these rogue planets is still a challenge. A new paper suggests that misaligned binary star systems are unstable shortly after formation, with more massive planets kicking out the smaller worlds. They predict that there should be many more low-mass planets out there to find as instruments improve.
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The Milky Way's Black Hole is Spinning as Fast as it Can

By Brian Koberlein - October 27, 2023 11:14 AM UTC | Black Holes
Is the supermassive black hole at the heart of the Milky Way (SagA*) spinning? And how fast? It's tricky to know how fast a black hole is spinning without an accretion disk, but astronomers can estimate using polar outflows of material streaming from the black hole. Researchers observed the region around SagA* with the Chandra X-Ray Observatory and estimated that it is spinning. In fact, it's spinning as quickly as the laws of physics will permit.
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A Fast Radio Burst Took 8 Billion Years to Reach Us

By Brian Koberlein - October 24, 2023 02:45 PM UTC | Cosmology
A newly discovered fast radio burst (FRB) absolutely smashed the record for the most distant ever discovered. The burst was found in June 2022 at Australia's ASKAP radio telescope after it had spent 8 billion years crossing the Universe. The FRB released the equivalent of 30 years of solar radiation in milliseconds. The burst could also help astronomers weigh the Universe, measuring how much gas it had to pass through on its long journey to reach Earth.
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JWST Looks at the Debris Disc Around a White Dwarf

By Brian Koberlein - October 22, 2023 04:00 PM UTC | Stars
White dwarfs are the ultimate fate of stars like our Sun, and one of the most exciting examples is located 95 light-years from Earth. In 2018, astronomers saw it suddenly flare up, suggesting that an exoasteroid was disrupted, leading to observations of dust and debris around the star. Astronomers think the star is surrounded by the remnants of its planetary system, crushed into a debris disk. Now, JWST has made its first observations of this intriguing star.
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In 1952, A Group of Three "Stars" Vanished. Astronomers Still Can't Find Them

By Brian Koberlein - October 21, 2023 11:59 AM UTC | Stars
In 1952, the Palomar Observatory imaged a close grouping of three point-like light sources, measuring 15th magnitude in brightness. It took another image an hour later, and the three objects had vanished. Follow-up observations scanned the area down to 21st magnitude and they were still missing. Now astronomers have used the 10.4-m Gran Terescopio Canarias, which should have seen anything brighter than 25.5 mag. Still nothing. What were they, and where did they go?
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