Betelgeuse To Blow Up Soon — Or Not

rubycodez writes "A wave of 2012-related hoopla has hit the internet about the star that makes the 'right shoulder' of Orion the hunter: Betelgeuse. Astronomer Phil Plait once again puts rumors to rest. The star will indeed explode as a type II supernova, and when it does it will be brighter than Venus when viewed from Earth, though not as bright as the full moon. It will be visible in the night sky for weeks, and could be visible in the day sky for a short time. But that event could happen today or 100,000 years from now, or as much as a million years from now. Since Betelgeuse is over 600 light-years away, its violent death will not harm Earth in any way, but will definitely provide a huge bonanza of scientific information about supernovae. As geeks, we can only hope the core of Betelgeuse undergoes catastrophic failure in our lifetime."

Comments

Soon?

[RabbitWho]

What they're saying is it might have blown up around 600 years ago... or not

Re:Soon?

[Kjella]

Long story short, our full motion is measured relative to the background radiation. The earth rotates around itself, around the sun, the sun rotates around the milky way and the milky way is moving itself. In total we move about 0.2% of lightspeed, and time dilation is relative to the fraction of c squared so time goes about 0.0004% faster than at rest. Imagine you stuck your finger in still water, the circle it'd make would continue to grow and the wave would go on forever but get thinner and thinner. Same thing with the universe, the distance to the edge keeps increasing but the earth and moon isn't being pulled apart by space "stretching". All this is really on a much grander scale though, in terms of a planet 600 light years ago it's like asking if you can find your way down to the corner store without taking into account that earth is round.

The difficulty is in trying to get an accurate angle measurement, even taking pictures from both sides of the earth we only get a ~13000 km wide angle which is small when you're trying to see an object ~5000000000000000 km away. For Betelgeuse wikipedia lists the distance as 643 ± 146 ly so the uncertainty is almost 300 ly. If we could travel even a tiny bit in any direction that'd matter on a stellar scale and photograph the sky we'd have much, much, much better estimates on the distances. That said, we can still do a lot more from earth or near earth than we have so far and there's plans for far better telescopes than today, first up probably the James Webb Space Telescope in 2014 or 2015. Also ground based telescopes keep getting larger and better, even though the atmosphere limits them somewhat.

Re:Soon?

[Ruie]

Stellar parallax is usually measured using positions of the earth at different points of the orbit around the sun, which provides a much longer measurement base.

Re:What about Ford Perfect?

[GreatDrok]

I don't know about Ford Perfect, but Ford Prefect may well have an issue with this.

Re:Already happened?

[dsanfte]

Calm down, he's obviously talking about his own inertial reference frame. And within his frame, he's correct.

Re:Let's hope that..

[mrsquid0]

It is extremely unlikely that Betelgeuse will produce a gamma-ray burst. The current thinking is that supernovae only produce gamma-ray bursts in stars that have been stripped of their hydrogen envelopes. Betelgeuse still has most of its hydrogen, and there is not enough time to lose it before the supernova is likely to happen. Even if Betelgeuse does produce a gamma-ray burst the bursts occur along the rotation axis of the star, and Betelgeuse's rotation axis is not pointed towards us. Fortunately, we do not have to worry about a gamma-ray burst from Betelgeuse, because it is close enough that such a burst would be rather nasty for us.