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Red supergiant star
Red supergiants are supergiant stars of spectral type K-M and a luminosity class of I. They are the largest stars in the universe in terms of physical size, although they are not the most massive. Stars with more than about 10 solar masses, after burning their hydrogen become red supergiants during their helium-burning phase. These stars have very cool surface temperatures (3500-4500 K), and enormous radii. The four largest known red supergiants in the Galaxy are Mu Cephei, KW Sagitarii, V354 Cephei, and KY Cygni, which all have radii about 1500 times that of the sun (about 7 astronomical units, or 7 times as far as the Earth is from the sun). The radius of most red giants is between 200 and 800 times that of the sun, which is still enough to reach from the sun to Earth and beyond.
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Space & Time News
August 1, 2025
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June 11, 2025 — By using a clever quantum approach that involves two "hands" on a clock one moving quickly and invisibly in the quantum world, the other more traditionally scientists have found a way to boost timekeeping precision dramatically. Even better, this ...
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June 2, 2025 — Researchers have engineered a laser device smaller than a penny that they say could power everything from the LiDAR systems used in self-driving vehicles to gravitational wave detection, one of the most delicate experiments in existence to observe ...
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Aug. 1, 2025 — Using a powerful mathematical tool, scientists have unveiled the intricate "ringing" of black holes, unlocking patterns missed for decades and laying ...
July 31, 2025 — A team of scientists has proposed a groundbreaking new theory on the Universe's origins, offering a fresh, radical take on the Big Bang's early ...
July 29, 2025 — Scientists at UC Merced have engineered artificial cells that can keep perfect time—mimicking the 24-hour biological clocks found in living organisms. By reconstructing circadian machinery inside ...
July 28, 2025 — Neutrinos, ghostly particles barely interacting with matter, may secretly be reshaping the fates of massive stars. New research suggests that as stars collapse, they form natural "neutrino ...
July 25, 2025 — In the sprawling Hydra constellation, 137 million light-years away, lies NGC 3285B—a dazzling spiral galaxy recently spotlighted by NASA’s Hubble Space Telescope. This cosmic beauty orbits the ...
July 23, 2025 — Astronomers have likely witnessed a planet forming in real time, seen inside a spiral arm of the HD 135344B protoplanetary disc—exactly where theory predicted. The direct light detection is what ...
July 22, 2025 — NASA’s Roman Space Telescope is set to embark on a deep-sky survey that could capture nearly 100,000 cosmic explosions, shedding light on ...
July 20, 2025 — A tiny object far beyond Pluto, newly discovered by the Subaru Telescope, could reshape our understanding of the early Solar System. Named 2023 KQ14, ...
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