"Exploding star a mere 12 light-years away"
And article says 11.5 millions light years away?
Exploding stars aren't an uncommon event in a universe with billions upon billions of stars in billions upon billions of galaxies – but catching an explosion in the act on our galactic doorstep is rare. (Well, 11.5 million light years away is, in astronomical terms, quite close by, and as I'll explain later, the type and …
"Exploding star a mere 12 light-years away"
And article says 11.5 millions light years away?
Thanks - missed a million there! Fixed.
Too late! [Evil_grin]: https://twitter.com/murphyslawyer/status/426113205459382272/photo/1
Very glad it's 11.5 million LY off - a mere 12 LY would not only ruin everyone's day, it would reduce the Solar System to highly ionised particles of toast.
Start building a bunker, space debris on the way...
Just a thought.
Well that is, unless Alpha Orionis or WR104 goes off in the near future, although if the latter happens and the jet is Earth directed we could end up seeing a brief white flash as our atmosphere ionises PDQ.
Now you've reminded me of (mind-numbingly inane) Oasis lyrics. Damn you. Damn you to Hell.
That's how light years work isn't it? This is really really old news that we're just receiving?
Old news to those close to M82, new news to us. No such thing as instant communications across the void. Yet, there will be those claiming it's happening in the here and now since the universe is only 6000 years old.
BTW, the sub-headline still says "12 light-years away".
In that far away galaxy, Space Obama had just announced Space Obamacare, when the Supernova ruined the announcement, rendering healthcare not mandatory but null and void.
And, everyone agreed before being vaporized, it was worth it, because it also made all buttholes who can't stop dragging their political propaganda into unrelated subjects null and void.
Long, long ago in a galaxy far, far away.
So six years from now, we see a second one go boom?
"Upon which progressotards in the forums saw their hotspots pushed, which were not of the nature liberated in the sexual revolution, rioted and started calling names, verily because their belief systems were bent and twisted and they didn't care about that starstuff when all was said and done."
>>Yes, if we ignore relativistic complications, when this star exploded humans were still around 11,000,000 years in the future.<<
Guess there's not much point in sending a 'sorry your star has blown up' card, then. Even first class, they'll be 20-something million years over it by now, hopefully moved on, don't want to reignite the pain by reminding them.
In Newtonian Mechanics there is no time delay because of finite signal propagation built into the equations. You can add one yourself, but that is not quite the same.
Local politics is for locals. Please rant about it at one of your fine fora for discussing your version of local politics.
Forget relativity, what about quantum physics? If there were no observers around when the star exploded (never mind that quantum physics hadn't been discovered either), then presumably it was in a superposition of exploded and unexploded states until the light reached us. At that point the star instantaneously - through spooky action at a distance - became fully exploded.
Of course, there may have been some earlier alien observers to fold into the wave function. But as we don't know whether they exist or not, that just makes it even more complicated.
And you thought Schrodinger's cat was a problem?
But surely nearby non nova stars and other high energy sources bounced photons, neutrinos, cosmic rays, x-rays and other stuff off the superposition thus observing it by interaction even with no conscious observers around.
There is a reason why in order to demonstrate superpositions we need still relatively small objects kept in hard vacuums at close to absolute zero, shielded from vibrations and in Faraday cages. As soon as the universe is allowed to interact with superpositions they tend to go 'poof'. No observers need apply.
At that point the star instantaneously - through spooky action at a distance - became fully exploded.
Are you trying to fit me up for somebody's star blowing up?
Well maybe. But OTOH, the finite speed of light provides pretty good isolation between the supernova and us until the light eventually arrives.The isolation is at least as good as you can get in any laboratory, because we know of nothing that can signal the state of the star to us faster than light in a vacuum. That's basically all the box is for in Schrodinger's famous cat-flavoured thought experiment - to isolate two macroscopic systems from each other.
As for all the matter the light encounters on the way - well that's part of the wavefunction that we haven't yet collapsed. It's like the air inside Schrodinger's cat's box. The intervening atoms are all in a superposition, until we see the light. Then everything collapses into a self-consistent state.
Of course, other interpretations are available. But they do tend to be just as weird.
hmmm yeah... And applying quantum principles to the macro world goes well for you?
Yes, and by the same token, this:
Exploding stars aren't an uncommon event
is unbridled speculation. All we know is that novae have been common in the past. They may have spontaneously stopped recently.
The Copenhagen interpretation of quantum mechanics really needs to go away. It's almost as bad as Deepak Chopra's interpretation of quantum mechanics, and I am NOT exaggerating when I say that.
because we know of nothing that can signal the state of the star to us faster than light in a vacuum.
Well, a star blowing up should be bad news for the entities living on nearby planets, but apparently it's not sufficiently bad to have arrived here before we actually observed the explosion.
Has pahhened before, and all of this will happen again. I can feel it in my bone.
However, in the near term, let us hope that that list of things being ticked off does not include ETs on their way to hijack us... Especiallly if any include Cavil's forces.
> Has pahhened before
Indeed. 11 million years before.
"Early hopes that neutrinos from the new explosion might be detectable from Earth, however, appear to have been dashed because of the dusty environment of the explosion"
Some mistake surely? Neutrinos aren't going to notice something as trivial as a dust cloud. You need a light year's thickness of lead to have a reasonable chance of stopping a particular neutrino.
Even at 12 million LY, I would think that it would be too far away to directly detect any neutrinos as they would be somewhat swamped by other sources. I believe one would have to be in our galaxy before we would be able to see an appreciable and identifiable burst from a supernova.
I don't know what the dust has to do with it.
Well this is guessing but -
Neutrinos assumed to be sent with radial symmetry (all directions equally).
A (very) small fraction of the neutrinos in our direction will be lost because of the dust.
A (very) small fraction of the neutrinos are coming in our direction (Total/area of sphere 11.4 light year radius)
Our detectors capture a (very) small fraction of the neutrinos coming in our direction.
Therefore, the astronomers think that the combination of effects are likely to result in an imperceptible change in the number of neutrinos detected relative to baseline - Can't do any science.
We detected neutrinos from 1987A - which was just outside the galaxy (50KPc), and our detectors were pretty insensitive back then.
yeh but we'd need to be over a 100 billion times more sensitive now rather than the barely an order of magnitude or so we've managed.
"You need a light year's thickness of lead to have a reasonable chance of stopping a particular neutrino."
Thus, if neutrinos do not materialise, it proves that there must indeed be a light-year's thickness of lead between the exploding star and us.
"How can this be?" I hear you cry. "We cannot detect such a large amount of lead, therefore it cannot exist!"
That's why I've just invented "Dark Lead" (tm).
It doesn't interact with anything apart from neutrinos, is totally invisible, and isn't very good for use as lead flashing as the rain tends to run straight through it, ruining ceilings and carpets.
I recently graduated with a degree in Astrophysics and I've been wondering what to do with my life. Now I know, a PhD in the theory of and a career searching for Dark Lead. Time to get started on that funding proposal....
Handy for keeping that Dark Rain off of my Dark Axminster though.
...our galactic doorstep
11.5 million light years might be close in astronomical terms but it's hardly on our doorstep.
500--1000ly would be much more exciting. Angling right, we'd probably even smell its 'breath'.
Kudos are due all the people involved as a pickup team of interested and dedicated amateur and professional astronomers. Its a group award.
I always thought the IAU (www.iau.org) was the arbiter of astronomical discoveries. As the article mentions a "telegram" (remember those?) I assumed this was the official announcement because telegrams used to be the way it was done. Maybe it still is.
However, I couldn't see anything obvious about it on the IAU website.
a good place to find out just how out of touch you can get since 6th form astronomy class.
Telegram? I'm not convinced telegrams supported hyperlinks...
Anybody here know how far away a supernova like this would have to be for the human race to survive it?
At a guess 11.5 Million Light Years....
"Anybody here know how far away a supernova like this would have to be for the human race to survive it?"
Anything closer than about 10 pc (about 33 ly) would cause problems for us.
"Exploding stars are common, nearly 50 stars blow up every second!" - drat, now I finally know where that pesky 50Hz hum any sensitive enough electronics picks up is really coming from! I'm not falling for that "powerline" hoax ever again...
" students at University College, London supervised by Steve Fossey are also credited with first spotting the supernova"
AFTER being told it had been found, they merely realised that they had an image but didn't spot what it was.
Many people may have an image, some may be earlier images, but if they didn't say "hey look, a supernova", sorry you did not discover it, Fossey and co. Investigating after the fact doesn't count.
If, one hour before both these groups, I just happened to point my camera phone in the correct direction while taking a piccy of an urban fox, and one pixel was a tiny tiny tiny bit brighter than its neighbours, could I claim that it was the super nova and that it made me the person who discovered it??? ;-)
People (like Tom Muxlow at Jodrell Bank) have been following developments in M82 for a long time; it has lots of relatively young supernova remnants and another supernova soon was highly likely (estimated about one every 30 years)
Icon: for Tom
the Hubble Space Telescope has pre-imaging of the galaxy, images longer before the star would have blown up, which may allow us to directly see the star
Says here Hubble has an angular resolution of 0.05 arcseconds. My rough calculation that even to see Betelgeuse at 3.6 AU diameter at 11 million light years would require an angular resolution of 10^-6 arcseconds, which could only be achieved with more like a 5 km-wide mirror.
And in spaaaaace!
What's more amazing is that using small telescopes (4 or 5" refractors) and some modern techniques, amateurs are imaging this thing from their back gardens!
Some fireworks display if one could watch this for a few minutes.
Just how fast does a neutrino travel if expelled from an exploding star?
Assuming no Dark Lead is in it's path of travel
well, considering a neutrino has a very, very small mass, it can be accelerated up to pretty close to the speed of light. From guess at the amount of energy available in a supernova, I'd say the neutrinos are all accelerated up to their maximum speed. The interesting thing is that although neutrinos have mass and hence have to travel a little slower than photons, they don't interact much with anything and travel in pretty straight lines, so photons while photons get deflected by gravity along the way and suffer from slow downs due to changes in permitivity, neutrinos can arrive sooner than photons from the same event.