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Star Betelgeuse - A red supergiant in the constellation Orion

One fascinating star is Betelgeuse, a red supergiant located in the constellation Orion. Here are some intriguing facts about it: 1. Size and Volume: Betelgeuse is immense—if placed at the center of our solar system, it would extend past the orbit of Mars. 2. Variability: It is a pulsating variable star, meaning its brightness changes over time; it has been observed to vary in brightness over several months. 3. Life Cycle: Betelgeuse is nearing the end of its life cycle and is expected to explode as a supernova within the next million years, a relatively short time in astrophysical terms. 4. Distance: It is located approximately 640 light-years away from Earth. 5. Cultural Significance: Betelgeuse has been significant in many cultures and is commonly referred to as the “Shoulder of the Hunter” in the constellation Orion. 6. Color Indicator: Its reddish hue signifies a cooler surface temperature compared to other stars, which gives it a distinctive appearance. Betelgeuse con...

Simultaneous X-ray and infrared observations of the galactic center

The supermassive black hole (SMBH) at the center of our Milky Way galaxy, Sagittarius A*, is by far the closest such object to us, only about 25 thousand light-years away. Although not nearly as active or luminous as other SMBHs, its relative proximity provides astronomers with a unique opportunity to probe what happens close to the "edge" of a black hole. Monitored in the radio since its discovery and more recently in the infrared and the X-ray, Sgr A* appears to be accreting material at a very low rate, only a few hundredths of an Earth-mass per year. Its X-ray emission is persistent, probably resulting from the rapid motions of electrons in the hot accretion flow associated with the black hole. Once a day there are also flares of emission that are highly variable; they appear more often in the infrared than in X-rays. Some submillimeter wavelength flares have also been tentatively linked to IR flares, although their timing seems to be delayed with respect to infrared events. Despite these intensive observational efforts, the physical mechanisms producing flaring around this SMBH are still unknown and are the topic of intense theoretical modeling.

from Astronomy News - Space News, Exploration News, Earth Science News, Earth Science https://ift.tt/2U6XSaF

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