The star Betelgeuse has been in the sights of astronomers for centuries, as it is one of the brightest stars in the sky along with Sirius. The red supergiant is very easy to identify in the sky thanks to the fact that it is part of the constellation of Orion, a constellation of which it is the brightest star. Hubble recently returned new data about Betelgeuse that suggests the massive star literally exploded, flinging much of its mass into interstellar space.
The path to becoming a supernova
The evolution of . The star is in the most important stage of its life, because it has already exhausted much of the fuel in its core that provided it with the energy necessary to maintain constant nuclear fusion.
It went from being a star with a normal mass to a red supergiant and researchers are targeting it to understand how it will continue its descent until it becomes a supernova. Recently the Space Telescope shed more light on this and captured the exact moment when Betelgeuse exploded, losing a substantial part of its visible surface.
Behavior never before seen in a red supergiant
The data collected by the telescope is of great importance, as it allows us to observe the cyclical moments in the evolution of an organism. Records from the Hubble Space Telescope suggest that Betelgeuse produced a gigantic surface mass ejection (SME) in 2019, behavior that has never before been observed in a normal star.
Our own host star, the Sun, also routinely ejects parts of its exterior (corona), events known as Coronal Mass Ejections (CMEs). However, the solar explosions are not as intense compared to the SME launched by Betelgeuse that took off 400 billion times more mass than a typical CME, so it was labeled as extremely strange behavior.
According to the National Aeronautics and Space Administration, the monster star is still slowly recovering from this catastrophic upheaval. “Betelgeuse continues to do some very unusual things right now; the interior is like bouncing,” explains Andrea Dupree from the Center for Astrophysics | Harvard and Smithsonian in Cambridge, Massachusetts.
The observations shed clues about how red stars lose mass at the end of their lives as their nuclear fusion furnaces burn out, before eventually exploding as supernovae.
“We have never before seen a large mass ejection from the surface of a star. We are left with something we don’t fully understand. It’s a totally new phenomenon that we can directly observe and resolve surface details with Hubble. “We are watching stellar evolution in real time.”
What caused the explosion?
NASA researchers explain that the massive burst “probably occurred due to a convection column of almost two million kilometers, bubbling up from the interior of the star.” They added that this large plume “produced shocks and pulsations that blew away part of the photosphere, leaving the star with a large cold surface beneath the dust cloud produced by the cooling of the photosphere.”
In other words, Betelgeuse’s photosphere fractured and much of it shot out into space. With a mass of several Earth’s moons, the piece of the photosphere that was thrown outward cooled to form a cloud of dust that blocked the light of the star seen by astronomers from the Earth’s perspective.
Although this moment is definitely conjunctural to understand the evolution of stars, it still does not show us that of Betelgeuse. The star’s surprisingly violent behavior is not evidence that the star is about to explode anytime soon. NASA said the mass loss event is not necessarily the sign of an imminent explosion; the red giant is still many millions of years away from becoming a supernova.