Some astro-physicists have calculated that the bright red giant star Betelgeuse in the shoulder of Orion will probably reach its supernova event within a few decades.
And I quote:
“CONCLUSION
We have found carbon-burning models that excite the radial fundamental mode, as well as the first, second, and third overtones. The
periods excited pulsation modes agree with periods of 2190, 417,
230, and 185 d that had been detected in Betelgeuse. On the HR diagram, these models are located within the allowed range of effective
temperature and luminosity of Betelgeuse. Beginning with a mass
of 19 𝑀⊙ at ZAMS (with a rotation velocity of 0.2 or 0.4 𝑣crit), the
models lose significant mass mainly in the core-He burning stage to
MNRAS 000, 1–11 (2023)
Pulsations of Betelgeuse 7
have a mass of 11 ∼ 12 𝑀⊙ in the core carbon-burning stage. A large
radius of about 1300 𝑅⊙ (needed for the long-period fundamental
mode) is supported by interferometric measurements of the angular
diameter combined with the distance. We conclude that Betelgeuse
should currently be in a late phase (or near the end) of the core carbon burning. After carbon is exhausted in the core, a core-collapse
leading to a supernova explosion is expected in a few tens (of) years.”
Note that last line, IN A FEW TENS OF YEARS.
So even an old guy like me may live to see a close supernova in the sky. That’s pretty exciting. Apparently Betelgeuse has reached the stage where it is fusing carbon into magnesium and based on the pulsations in the size and brightness of the star, it’s about to run out of carbon. Since it’s not big enough to go through another higher round of fusion it’s going to collapse into a neutron star via an incredibly violent supernova. It will be as bright as the half moon and will be seen even during the day. Sounds pretty exciting.
