🚨Betelgeuse explosion alert🚨
When Betelgeuse eventually goes supernova, its newly discovered companion, Betelgeuse B, will survive the catastrophic explosion but will be violently slingshotted out of the star system to become a "runaway star."💫
Because Betelgeuse B is significantly more massive than originally predicted, estimated at 2.6 to 3.1 times the mass of our Sun, it is incredibly dense and tightly bound by its own gravity. When the primary supergiant detonates, the companion will be subjected to two extreme physical events:
The Blast Impact (Ablation)💥
When the supernova shockwave and stellar ejecta slam into Betelgeuse B at a fraction of the speed of light, the sheer kinetic force and extreme radiation will intensely heat the companion's facing hemisphere. This impact will strip away its outer atmospheric layers, which is a process known as ablation. While the companion will be heavily bruised, it will not be destroyed. Instead, its remaining atmosphere will become heavily polluted with the newly forged heavy elements (like iron and calcium) from the dying supergiant.
The Gravitational Slingshot💫
The most permanent change to Betelgeuse B will be orbital. Currently, the immense mass of Betelgeuse (roughly 15 to 20 solar masses) acts as the gravitational anchor keeping Betelgeuse B trapped in its roughly 6-year orbit.
During the supernova, Betelgeuse will eject the vast majority of its mass into deep space in an instant, leaving behind only a lightweight core (likely a neutron star weighing less than 3 solar masses). Because the binary system suddenly loses more than half of its total mass, the gravitational "glue" holding it together vanishes.
Betelgeuse B will immediately become gravitationally unbound. Like letting go of a spinning tetherball, the companion will fly off in a straight line at its exact orbital velocity at the moment of the explosion. It will spend the rest of its life hurtling through the Orion constellation at tens of kilometers per second as a standalone "runaway star," leaving the glowing nebula of its former partner behind.
ALT This graphic illustrates the scenario for the processes that create a Type IIb stripped-envelope supernova, in which most, but not all, of the hydrogen envelope is lost prior to the primary star’s explosion. The four panels show the interaction between the SN 2001ig progenitor star, which ultimately exploded, and its surviving companion: 1) two stars orbit each other and draw closer and closer together; 2) the more massive star evolves faster, swelling up to become a red giant. In this late phase of life, it spills most of its hydrogen envelope into the gravitational field of its companion; as the companion siphons off almost all of the doomed star’s hydrogen, it creates an instability in the primary star; 3) the primary star explodes in an SN; 4) as the supernova’s glow fades, the surviving companion becomes visible to Hubble; the faint remnant of the supernova, at lower left, continues to evolve but in this case is too faint to be detected by Hubble. Credit: NASA/ESA/A.Field/STScI.