Betelgeuse, the red giant in the Orion constellation, has been fascinating astronomers for years with its unstable nature. But with the James Webb Space Telescope (JWST), scientists are studying sinister new information that might rewrite what we thought we understood about the star's sinister dimming episode in late 2019. The data indicates that something more sensational might be happening—and it's sending the world of astronomy shivers.
A Star on the Edge
Betelgeuse, some 650 light-years away from Earth, is a red supergiant that is coming to the end of its life. It's huge—about 1,000 times larger than our Sun—and when it ultimately dies, it will explode in a spectacular supernova even visible in the daytime from Earth.
Late in 2019 and early in 2020, Betelgeuse surprised astronomers by fading radically, falling to nearly 40% of its typical brightness. The phenomenon incited frenzied speculation: Was it finally on the verge of going supernova?
Scientists later attributed the fading as a product of a gigantic surface cooling event accompanied by an ejection of a dust cloud. But this was not the end.
James Webb's Eerie New Clues
The James Webb Space Telescope, whose advanced infrared capabilities have been focused on Betelgeuse of late. What it discovered is in some ways very interesting—and a bit disturbing.
In a new study out this week, JWST saw complex molecular behavior and unanticipated chemical signatures in the dusty shell surrounding Betelgeuse. These patterns indicate that the event was not an isolated phenomenon but part of a chain of violent events, maybe triggered by the internal convulsions of the star as it moves closer to its demise.
Perhaps the most disturbing sight was an abnormally shaped cloud of material unfolding swiftly away from the star. This "ghostly" cloud is asymmetrical and much denser than usual stellar emissions, casting doubts about the forces operating within Betelgeuse.
There's something happening below the surface—literally," said Dr. Eleanor Hughes, an astrophysicist at the European Southern Observatory. "These types of expulsions could be Betelgeuse losing its outer layers before it collapses."
Could the End Be Near?
Astronomers are careful to cool the speculation despite ominous data. Supernovae are notoriously difficult to predict. Betelgeuse might blow tomorrow—or not for another 100,000 years.
Nevertheless, the observations made by JWST are the strongest indication to date that the star is experiencing unusual transformations. Infrared imaging detected shockwaves passing through the outer layers of Betelgeuse, and researchers think that these are the consequence of deep stellar tremors. These tremors are analogous to solar quakes on our Sun and could be indications of an unstable core.
The Webb data provides us with front-row seats to the last moments in a star's life," said Dr. Lucia Moreno, a theoretical astrophysicist at NASA's Goddard Space Flight Center. "It's like witnessing a slow-motion explosion in action."
Watching the Skies
All we can do for the time being is wait—and observe. Betelgeuse is still among the most observed stars in the night sky, and telescopes across the globe are trained on it. The Webb telescope will continue to observe it closely in the coming few years.
If Betelgeuse blows its top during our lifetimes, it will be an event of cosmic historical significance—visible to the naked eye, and an unusual opportunity to see a star die close up (from a comfortable distance).
Meanwhile, the eerie statistics from JWST are both a portent and an awe. The universe is reminding us exactly how alive—and volatile—its stars remain.
0 Comments