Darkside wrote:
Something really crazy might be about to happen in our galactic neighborhood, something massive, something life changing, something that will change our view of the stars forever.
Betelgeuse, the bright orange shoulder of Orion has long been known to be a red supergiant star. It's so big, and so close (galactically speaking) that it is the only star other than our sun that we have been able to resolve as more than a singular point of light in the sky. We can actually resolve the disc of the star. Were it to be in place of the sun, its surface would extend beyond the asteroid belt between mars and jupiter, and may actually extend to the orbit of jupiter.
So whats changing? Betelgeuse is a red supergiant as noted before, and thus when it dies, it will go supernova. A supernova a a dramatic death of a star. It happens once the core of the star can no longer fuse heavier and heavier elements and give off nuclear fusion energy. For a star like our sun that will likely be when its helium reserves exhaust. Our sun will expand, shed its outer layers and eventually cool into a dwarf star. But Betelgeuse can fuse heavier elements and still extract energy from them. However, eventually it will be left with an iron core and when that happens... boom.
A supernova will emit nearly as much light in a few weeks as an entire galaxy does in that timespan. And this one is in our backyard.
Why do we think it might be happening now? Betelgeuse is rapidly dimming, something we believe will happen just before a detonation. Back in october, betgeuse was the 9th brightest star in the sky. Today, it ranks 20th. And it's getting dimmer.
If betelgeuse were to go supernova, it would be about as bright in the sky as a full moon. Maybe brighter. The event could last for months. Then, one of the most familiar constellations in the sky (and the personal favorite of your pal Darko) will be forever changed.
What's the catch? Well, betelgeuse is a variable star. It does dim and brighten again on two different cycles, one roughly 6 years and one of 425 days. It may be the synchronous point of those two cycles that's causing this historic dimming. Interestingly enough our own sun is going through a synchronous dual cycle right now of it's own, resulting in the deepest solar minimum in hundreds of years. But back to Betelgeuse. It's possible that the star is just going thru a cycle, and if so we should notice it brightening up in less than 2 months. Many astronomers are fairly confident it will be another 10,000 to 100,000 years before it goes. It's also possible its gonna blow very, very soon.
If Betelgeuse were to go supernova, it's weird to think that it actually exploded sometime in the 1400s. It just took that long for the light to reach Earth. Imagine that, maybe a hundred years before Columbus sailed to the Americas the star blew up and we're just now observing it.
I spent some time outside last night looking at my favorite constellation. Betelgeuse is certainly dimmer. It's not something you need special instruments to see. You can just tell by looking at it. Imagining the Hunter without the same familiar shape is... well it's hard to describe how it feels. That formation has been there, stable in the sky for 10 million years. Every pair of human eyes that has looked to the sky and seen it has seen it just the way was see it today. Could it be different forever in just a few short months?
The last supernova in our galaxy was in 1604. This is indeed a rare event.
So when you go outside, maybe take a moment to gaze upon Orion the Hunter, and appreciate it. It may change forever. And you may witness it.
So here's a plot of the brightness of Betelgeuse over the last 2 and a half years or so to illustrate just how much dimming we've seen.

Pretty steep decline. And it's still declining.
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"Play until it hurts, then play until it hurts to not play."http://soundcloud.com/darkside124 HOF 2013, MM Champion 2014
bigfan wrote:
Many that is true, but an incomplete statement.