What the heck is Betelgeuse doing?
The red supergiant star marking the constellation Orion's right shoulder is one of the most famous in the sky (at least one supernatural comedy movie has, I admit, helped); for one thing it's a ruddy color that stands out from most other stars, and for another it's one of the brightest stars in the sky.
Usually, it's the 11th brightest star. But it's been dimming substantially over the past couple of months, and given its current status it's now tied for 24th. That's quite a fall!
This has prompted a lot of discussion about it possibly exploding as a supernova, but that's extremely unlikely for now*. Our best estimate is that it won't explode for another 100,000 years, so don't hold your breath.
But then why is it dimming? We know it's a variable star, changing its brightness up and down by a small percentage over time, usually on a roughly 420-day cycle. This due to the way the upper atmosphere of the bloated star traps light and heat, changing its size and brightness, which is common for red supergiants. It's likely this is a more extreme version of that.
To try to find ...