[Canadian_Mind]

Mr_Canada Mr_Canada:

So the article says it will shine light throughout day and night for two weeks.

I'm having trouble understanding just how bright these thing is going to be, is night going to be obviously ruined by a flaming explosion over 600 lightyears away? Cause those two weeks probably won't be a lot of fun.

Can't wait for the doomsayers though

bright enough to be seen during daytime. Likely somewhere between the brightness of the moon and the brightness of the sun.

[Public_Domain]

[DanSC]

The same thing happened back in 1054, when a supernova created what is now the Crab Nebula. The Chinese kept very good records of it, but oddly enough Europe didn't bother to write about it.

There actually is an array of 1-meter telescopes run by Georgia State at Mount Wilson Observatory above Los Angeles that has enough angular resolution to actually see the disk of a star and not just a point of light. I went on a tour there one (hence I unfortunately can't back this up with a link), but they've measured that the radius of Betelgeuse is shrinking. The supernova could easily happen in our lifetimes.

I just hope governments have contingency plans written up for when it does happen. No one will be in danger from the supernova, but people who don't know what's going on will go insane and it could lead to riots or cult activities.

[Canadian_Mind]

Mr_Canada Mr_Canada:

It'll be a fascinating experience if it happens sooner rather than later and it's not freaking crazy

What do you mean by freaking crazy? There is potential for the night sky to be lit up like twilight for up to 2 weeks. 2 weeks isn't a significant amount of time, so enjoy the experience.

[GreenTiger]

hurley_108 hurley_108:

This is all my semi-informed speculation. I may be wrong, but I hope not. It's also predicated on us not moving much farther away from Betelgeuse by the time it does blow.

Eta Carinae is a much more likely candidate for a within-our-lifetimes supernova as it's much more massive even than Betelgeuse, and has been displaying clear signs of major instability within recorded history.

Unfortunately, it's not visible from Canada, being well into the southern celestial hemisphere (Betelgeuse is at about 7° north, so it's visible even from much of the southern hemisphere, but Eta Carinae is almost 60° south). It is, though, ten times farther away than Betelgeuse so when it does explode, it'll have its impact much diminished.

However, being at 60° south, if one were in the southern hemisphere, it would be seen to shine day and night if one were at at least 30° south latitude (~Sydney or farther south). If Betelgeuse blows in Summer, it will have the sun to compete with whhereas if it blows in Winter, we'll be able to read by it at night as I've heard people were able to when the Crab supernova blew almost a thousand years ago.

What will be most interesting, though, will be watching the rapid evolution of the nebula that Betelgeuse will spawn. Being 10 times closer than the Crab nebula, everything will look 10 times bigger and 100 times brighter (light falls off as the square of distance). The nebula may even be visible to the naked eye. The Crab is about a fifth the angular diameter of the full moon after a millennium, but it might only take 100 years for Betelgeuse's nebula to reach that size being so much closer, and it will be brighter not only by being closer, but also by being younger and physically smaller. And in a telescope, it would be an incredibly awesome sight.

Sorry for geeking out, but space is amazing, and anybody who is alive when Betelgeuse goes will be in for a much bigger treat than a mere second sun for a couple of weeks.

Not geeking out at all, space IS amazing

[PostFactum]

And water will not boil away?

[Khar]

PostFactum PostFactum:

And water will not boil away?

Water will not boil away, or boil at all really. This would be more like the endless nights in the Yukon than anything else for two weeks, from what I've read on the topic. Our atmosphere is made of sterner stuff than that.

Er, feel free to skip this, the space dork inside me was screaming to get out.

In fact, just to put it all in perspective, the asteroid which struck the Earth and caused the extinction of the dinosaurs about 65 million years ago displaced or vapourized about 5,520 billion gallons of water, or 5.52 trillion gallons of water. This is mostly from memory on my part. This assumes an asteroid of similar size to that one struck water (potentially deeper, so the asteroid causing that mass extinction might have removed even less).

This sounds like a lot... until we remember that the Earth has 326,000,000,000,000,000,000 gallons of water. That's 326 million... trillion. 326 times a million trillions. While it's not all accessible, not even an extinction level event could "boil away our water." It directly displaced or vapourized 1.69325153E-12% of the world's water supply, or 0.00000000000169% of the world's water supply. Of course, it impacted much more than that in the resultant shockwaves and such, but even an asteroid striking our ocean does that little direct damage to the water supply. Remember that the extinctions were due to a dust cloud and firestorms, and the following climate changes from acid rain through severe temperature changes. The actual water supply was largely unaffected -- just everything within it died due to problems like, say, acidification, which we would not see in this type of event and which could be corrected for anyways. Other events, such as a potential mass extinction due to glaciation (Cambrian–Ordovician extinction event) and another due to anoxia (Ireviken event), did not remove water -- just made it less friendly to live in by changing oxygen levels or the form water was in.

The water outlived 75% of all species due to that mass extinction event when we lost the dinosaurs. The amount of water on Earth did not suffer a horrible blow. Hell, when Earth was being formed into a protoplanet and the solar system was still forming, water couldn't have been present, since it's too volatile a molecule to have been there during formation -- all that water had to be delivered afterwards. If water is boiled away, we would have beaten it to being boiled away long before -- water would outlive humanity in any situation which could destroy it, I would think.

Anyways, supernovae rarely have large impacts on Earth's biosphere. To impact us, they'd have to be (relatively) close to us, and most are not -- although an extinction event has been related to a supernova in the past (by a minority of experts) with the Ordovician–Silurian mass extinction, where 60% of all species were eradicated. It should be noted this is the only suggested event which has severely impacted Earth in such a way -- while ions on Earth can show when we have last been impacted by supernovae, the small impact demonstrated by these ions show how little they actually impacted Earth as near-Earth supernovae. There are some types which might effect us far more powerfully, but we simply don't have the information on that. It should also be noted that what occurred was suspected to have been a hypernova, not a supernova (it's bigger, more than 100 times more powerful cousin) hence why the potential for gamma radiation on that level is so rare -- only one of those happen in our galaxy every 200 million years, and having one in our neighbourhood is just plain horrid luck.

Good news -- none of those exist close enough to damage Earth anymore. The last one which caused that much death was 8000 lightyears from here -- and we've watched these things go off easily in other galaxies, hundreds of millions of lightyears away. We can watch which ease something occurring in an entirely different galaxy of stars and supernovas since it's that spectacular, and it only happened 0.0033333% of the distance away from us -- no wonder it hurt us. But it didn't boil away our oceans -- or even wipe out all life. Something which impacts entire galaxies significantly, something more than 100 times as powerful as a supernova, something which collapses directly into a blackhole, creating a relativistic shockwave approaching the speed of light, and it couldn't wipe out all life on a world which was next door (although it likely set it back a bit ). The only one left which really could impact us is the IK Pegasi, another supernova potential, 150 lightyears from us, but by the time it goes off, it could be many times that distance from us, although likely still able to impact us (although to what degree is still speculated, definitely not an extinction level event and definitely not for millions of more years).

[hurley_108]

Mr_Canada Mr_Canada:

So the article says it will shine light throughout day and night for two weeks.

I'm having trouble understanding just how bright these thing is going to be, is night going to be obviously ruined by a flaming explosion over 600 lightyears away? Cause those two weeks probably won't be a lot of fun.

Can't wait for the doomsayers though

Astronomical brighness is measured in magnitude, and higher magnitudes are dimmer. Five magnitudes difference represents a 100-fold difference in brightness, and it's a logarithmic scale so a 1-mag difference is about 2.5 times difference in brightness. That's the short of it.

The sun shines at mag -27, the full moon at about -12. Venus is about -4. Stars range from about -1.4 (Sirius, the brightest star) to the limit of naked eye visibility at about 6 and further on up.

Using the brightness of SN1987A, a supernova of the type that Betelgeuse will undergo (there are several types of supernova) as a reference, Betelgeuse's supernova will probably shine at somewhere around -9. So the moon will probably still be brighter, though Betelgeuse will look more brilliant because it'll still look like a star. If, though, it manages to reach the brightness of a type I supernova, it might reach the same -12 brightness as the Moon. So it won't light up the night like a second sun, no.

[hurley_108]

DanSC DanSC:

The same thing happened back in 1054, when a supernova created what is now the Crab Nebula. The Chinese kept very good records of it, but oddly enough Europe didn't bother to write about it.

Didn't bother to, or deliberately ignored because it went against their religious dogma that the heavens were immutable?

[djakeydd]

OH MAN, where is the tinfoil when you need it, and they say ppl who question the msm are nuts..

[Proculation]

$1:

Brad Carter, senior lecturer of physics at the University of southern Queensland in Australia, told the London Telegraph that the blast could happen in the next few months . . . or any time over the next million years. Talk about an open-ended timeframe.

When I read that, it reminds me of the network Distributed.net: there are (example) 850,000,000,000,000,000 possibilities to find the proper key to crack the password. If your computer tries 850,000 keys/seconds, that means that it will take you at the most 1,000,000,000,000 seconds to find the key OR, you have 1 change in 1,000,000,000,000 to find the key in the next second.

[PublicAnimalNo9]

djakeydd djakeydd:

OH MAN, where is the tinfoil when you need it, and they say ppl who question the msm are nuts..

Based on this comment and the one in the other thread, I'd hazard a guess that astronomy and astrophysics ain't yer strong suits.

[Proculation]

PublicAnimalNo9 PublicAnimalNo9:

djakeydd djakeydd:

OH MAN, where is the tinfoil when you need it, and they say ppl who question the msm are nuts..

Based on this comment and the one in the other thread, I'd hazard a guess that astronomy and astrophysics ain't yer strong suits.

djakeydd has a strong suit beside conspiracies ?

[SprCForr]

It's all too late. The tipping point is here and the industrialized countries need to address the AGLP* issue. The science is settled. Will our children ever see stars?

*Anthropogenic Global Light Pollution. Yeah, I went there! lol