But many astrophysicists warned that the supernova speculation was wishful thinking. Betelgeuse is more than 16 times the mass of the Sun, and times its width — so big that if it were located at the centre of the Solar System, it would engulf the orbits of all the planets up to Mars. How to blow up a star. The images clearly showed that the bottom left-hand part of the star — as seen from Earth's Northern Hemisphere — had dimmed dramatically, and that the position of the darker region did not change substantially over the imaging period.
This indicated that the dim spot was caused by a cloud of dust that had been spewed by the star itself, and was moving roughly in the direction of the line of sight, rather than passing by. This enabled gas that the star had spewed out in the previous year to condense quickly into dust, blocking out light from the star. This scenario was the one that fit the data best, as the researchers confirmed by running more than 10, computer simulations.
Nature , — Article Google Scholar. Joyce, M. But images from December reveal a more oval-shaped star, with a large, shadowy area covering the southern hemisphere.
The mystery is far from solved, but Guinan and his colleagues are grateful that Betelgeuse is brightening again while they can still see it. Soon, the red giant will slide across the sky close to the sun, hiding in the daytime light until fall. All rights reserved.
Science News. This image of Betelgeuse, one of the brightest stars in the sky, is a color composite made from exposures taken as part of the Digitized Sky Survey 2. Share Tweet Email. Why it's so hard to treat pain in infants. This wild African cat has adapted to life in a big city. Animals Wild Cities This wild African cat has adapted to life in a big city Caracals have learned to hunt around the urban edges of Cape Town, though the predator faces many threats, such as getting hit by cars.
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Go Further. Only about ten supernova have been seen with the naked eye in all recorded history. Now we can revisit ancient astronomical records with telescopes to discover supernova remnants like the brilliant SN witnessed in AD whose explosion created one of the brightest objects ever seen in the sky.
Unfortunately, latest research suggests we all might be waiting another , years for Betelgeuse to pop. However, studying this recent dimming event gleaned new information about Betelgeuse which may help us better understand stars in a pre-supernova state. For their entire lives, stars are in a struggle to balance against the inward crushing force of their own gravity using the outward force of their own energy — a state known as hydrostatic equilibrium.
Any disruption of this balance causes changes in the star — some dramatic others cataclysmic. Gravity is both the beginning and end of a star. Gravity draws the raw material to create a star, hydrogen gas from the interstellar void, and crushes it together. As long as a star has a supply of hydrogen, it can support its own weight and achieves a balanced sphere. This is where a star gets a second life — albeit in a new form.
The increased temperature radiates outward to supplies of hydrogen that remained in layers outside the core that were previously too cold to achieve fusion. This shell of hydrogen outside the core now ignites, but burning this outer shallower layer causes the star to swell.
If the star is massive enough, rising temperatures in the core will also ignite helium which accumulated as a byproduct of burning hydrogen. It is now brighter higher on the Y axis and redder farther right on the X axis. A red dwarf and red giant may occupy the same position on the X axis colour-wise, but the giant will be much brighter and therefore higher on the Y axis in the one of the giant branches. Red Supergaints like Betelgeuse are in the final stages of their lives. The new study says both could happen together.
In fact, previous observations show that the star had started to undergo some loss of mass, releasing large quantities of gas a year before the dimming event. But while the findings do not support a supernova event, they do not contradict the fact that Betelgeuse is still expected to undergo a supernova explosion at some point in the future.
The event would occur suddenly and is impossible to predict. It is thought that this will happen within the next , years.
The anticlimactic findings, however, are extremely valuable to the field of stellar physics research. They raise questions, such as whether other red supergiants undergo dimming events. They also offer insights into the lifecycle of such large stars, and the future of our own. India needs free, fair, non-hyphenated and questioning journalism even more as it faces multiple crises. But the news media is in a crisis of its own.
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