A neutron star? Or, does Betelgeuse have what it takes to collapse into a Black Hole? Scientists are still at a loss as to understanding why the exist, how they come to be, and what actually happens to the things pulled into them. To put it simply, a black hole is essentially a place where gravity pulls so strongly that not even light can escape, hence they appear like black disks.
They can come in different sizes and are born in a number of ways. Stellar black holes, like the one Betelgeuse might become, are born when massive stars collapses in on itself during a supernova. For a star like Betelgeuse, one of two outcomes after it dies are possible: its either it becomes a neutron star, or a black hole. Whether its one or the other depends on the amount of masses left over after the supernova event. If the remaining material in its central region is anything less than 3 solar masses, then in all likelihood Betelgeuse will rest in peace as a neutron star, and can be seen as a pulsar in our night sky.
A paper published in the Oct. But what was it up to, if it was not on the verge of exploding? As results from telescopes all over the world and in space flooded in, most astronomers have fallen into two camps.
If the dust theory proves true, it could have profound implications for the origins of complex chemistry, planets and even life in the universe. Red supergiants are surrounded by diffuse clouds of gas and dust that are full of elements that are forged only in stars — and those clouds form before the star explodes. Even before they die, supergiants seem to bequeath material to the next generation of stars.
Perhaps an asymmetrical dust cloud was to blame. That left dust as a reasonable explanation. A strong vote for dust came from Dupree, who was watching Betelgeuse with the Hubble Space Telescope. Like Guinan, she has a decades-long relationship with Betelgeuse. In , she and colleague Ronald Gilliland looked at Betelgeuse with Hubble to make the first real image of any star other than the sun.
Most stars are too far and too faint to show up as anything but a point. Betelgeuse is one of the few stars whose surface can be seen as a two-dimensional disk — a real place. By the end of , Dupree was observing Betelgeuse with Hubble several times a year.
She had assembled an international team of researchers she calls the MOB, for Months of Betelgeuse, to observe the star frequently in a variety of wavelengths of light. In late , Betelgeuse started dimming V curve, right more than its normal up and down V curve, left. The blue and green dots are brightness measurements from ground-based observatories. But from September through November, just before the dimming event, the star gave out more ultraviolet light — up to four or five times its usual UV brightness — over its southern hemisphere.
The temperature and electron density in that region went up, too. And material seemed to be moving outward, away from the star and toward Earth.
That could be one way that red supergiants shed material before exploding. Once it had fled the star, that hot stuff cooled, condensed into dust and floated in front of Betelgeuse for several months. As the dust cleared, Betelgeuse appeared brighter again. In the July 1 Astrophysical Journal Letters , Dharmawardena and colleagues published observations of Betelgeuse that ran counter to the dust explanation.
Dust should have made Betelgeuse look brighter in those wavelengths, as floating grains absorbed and reemitted starlight.
If anything, the star dimmed slightly. Infrared observations with the airborne SOFIA telescope should have found the glowing signature of dust too, if it existed. Multiple cycles syncing up could explain why the dimming was so extreme. It looks like all three cycles might have hit their brightness nadirs at the same time in late , Guinan says.
Betelgeuse is one of a handful of stars on which star spots have been directly seen. This one would need to cover at least half, maybe up to 70 percent. Analyses are still coming in.
A few observations came in right under the wire. The Complete Star Atlas. Astronomers simulated what humans will see on Earth when the star Betelgeuse explodes as a supernova sometime in the next , years. A plume of gas nearly the size of our solar system erupts from Betelgeuse's surface in this artist's illustration of real observations gathered by astronomers using the Very Large Telescope in Chile. Aboriginal Australians may have even worked it into their oral histories. They also included observations gathered during Supernova A, which exploded in the Large Magellanic Cloud.
Supernova seen from Earth With all the speculation about what a Betelgeuse supernova would look like from Earth, University of California, Santa Barbara, astronomer Andy Howell got tired of the back-of-the-envelope calculations. This comparison image shows the star Betelgeuse before and after its unprecedented dimming. This collage zooms in on the constellation Orion left to one of the sharpest images ever taken of Betelgeuse far right. A nearby supernova could have caused the Devonian mass extinction.
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Astronomy Puzzles. Jon Lomberg Milky Way Posters. Astronomy for Kids. Sign up. Table of Contents Subscribe Digital Editons. A chronicle of the first steps on the Moon , and what it took to get there.
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