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Supernova 2011b Gradually Fading

timothy posted more than 3 years ago | from the worth-it-for-the-pictures-and-reflections dept.

Space 122

An anonymous reader writes "The recent stellar explosion known as 'supernova 2011b' is gradually fading after outshining its host galaxy for over a month. The explosion first flared up in early January, and peaked at magnitude 12.9, putting it within the reach of many amateur telescopes. The host galaxy, NGC 2655, lies 64 million light years away, meaning that the star exploded while the dinosaurs still roamed the planet. My own sketches are available at gkastro.tk/."

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122 comments

Here's my sketch (5, Funny)

NEDHead (1651195) | more than 3 years ago | (#35108766)

                *

That's an old sketch. Here it is today. (5, Funny)

Anonymous Coward | more than 3 years ago | (#35109078)

Re:That's an old sketch. Here it is today. (-1)

Anonymous Coward | more than 3 years ago | (#35109506)

GP made an original, unique, brilliant, ingenious remark. You, however, simply tried copying it and therefore pay for the actual ingrained stupidity within the joke. GP gets the reward of a beautiful +5 Funny, for his incredibly well planned-out and executed graphic design, but you, sir, receive a fucking +1. NEDHead will be remembered when the Sun is fading out, but you will have been forgotten by everyone several moments after them witnessing your muddled attempts at humor (which just so happens to coincidence with the commencement of the fading of Supernova2011b!)

With my 240x mag filter (0)

Anonymous Coward | more than 3 years ago | (#35111468)

({@})

Dinosaurs? (4, Informative)

name_already_taken (540581) | more than 3 years ago | (#35108770)

I thought the dinosaurs died out 65 million years ago?

That means they were already dead for a million years, 64 million years ago.

Re:Dinosaurs? (1)

sznupi (719324) | more than 3 years ago | (#35108964)

Or even: the supernova happened now (well, a month ago) - as far as our frame of reference (and of dinosaurs, or what's left of them) is concerned.

Re:Dinosaurs? (2, Informative)

Anonymous Coward | more than 3 years ago | (#35109074)

NO. In our frame of reference it happened ~64 million years ago and we are just now finding out about it. The only frame of reference where it occurs "now" is the frame of reference of the photons traveling at the speed of light. Relativity doesn't work that way.

Re:Dinosaurs? (1)

tm2b (42473) | more than 3 years ago | (#35109146)

Actually, it does. The relativistic interval is 0 along the light cone from the event, which is how relativity defines simultaneity in a given interial frame.

Re:Dinosaurs? (-1)

Anonymous Coward | more than 3 years ago | (#35109294)

Actually, it does. The relativistic interval is 0 along the light cone from the event, which is how relativity defines simultaneity in a given interial frame.

That's how yo mama defines this black cock in a given nigga frame when she deep throats it.

Re:Dinosaurs? (0)

sjwt (161428) | more than 3 years ago | (#35109366)

And 0 is how anyone describes yours, go troll else where ac.

Re:Dinosaurs? (0, Flamebait)

Anonymous Coward | more than 3 years ago | (#35109480)

And 0 is how anyone describes yours, go troll else where ac.

Says the guy who took the bait and had to respond because he just couldn't resist after all.

Dumbass.

Re:Dinosaurs? (0)

Ethanol-fueled (1125189) | more than 3 years ago | (#35109622)

Have you ever seen a human woman fellate a horse?

You gotta wonder what's going through the horse's mind when it happens:

Man, that two-legger sure has a nice mane. Hey, what's she doin' goin' under me like that for? Hey, Hey! She's handling the thing I pee with! Uh...I dunno what she's doin' to it but I'm feeling all tingly...huh. Huh. Hrrrhrrhrrhrrhrr. Prprprprprprprprrrr...ReeHEEHEEHEEHEEHEEHEE!

Whoa, Nelly! That was much better than my weekly apple!

Re:Dinosaurs? (1)

Issarlk (1429361) | more than 3 years ago | (#35110270)

I doubt that horses think in english.

Re:Dinosaurs? (1)

Angeret (1134311) | more than 3 years ago | (#35111270)

Aw, c'mon, by that time I doubt the horse is thinking anything at all - if he's like most horny heterosexual human males (and I'm not explaining that to any basement dwellers either!)

Re:Dinosaurs? (1)

Anonymous Coward | more than 3 years ago | (#35109412)

Actually, it does. The relativistic interval is 0 along the light cone^H^H^H^H^H sphere from the event, which is how relativity defines simultaneity in a given interial frame.

FTFY

Re:Dinosaurs? (4, Informative)

wierd_w (1375923) | more than 3 years ago | (#35109476)

Sorry AC, Light cone is the correct terminology when discussing relativistic phenomena. It has to do with how the posibility function looks when graphed; it creates a cone shaped region. anything inside the cone is observable at some point in the lifetime of that photon generating event, anything outside that cone is not observable.

The point that the GP was trying to drive home is that relativity outright rejects the notion of "standardized time", and also any notion of a "universal reference point" from which to observe without also suffering from relativistic effects.

This is because time is a variable under relativity, and because all objects are in motion, and thus subject to relativistic effects. Your suggested correction of "light sphere" may not look very spherical from a specific vantage point, due to non-uniform spacial curvatures interacting with that light.

Long story short, your correction is in fact, incorrect. Sorry.

Re:Dinosaurs? (1)

SETIGuy (33768) | more than 3 years ago | (#35109548)

The relativistic interval is 0 along the light cone from the event.

The relativistic interval is not a time interval, so it is incorrect to say that the event happened recently, unless you're in a very special frame. (i.e. Traveling along with the light from the supernova directly from the supernova to the earth at very close to the speed of light). It would have been very difficult for you to post your message from that frame. Since you're in essentially the same frame as we are, the supernova happened 64 million years ago.

Re:Dinosaurs? (1)

sznupi (719324) | more than 3 years ago | (#35110096)

One could think a century is enough... (too bad it's apparently sufficient if something sounds convincing, reasonable; which doesn't really work in this particular field)

Neither way of saying is particularly right or wrong (unless you insist on our locality). Just now observing something is simultaneity / there is no difference / it didn't exist for us (BTW, there is hardly any "now" for a photon, that would need time

Re:Dinosaurs? (1)

Urkki (668283) | more than 3 years ago | (#35109788)

Or even: the supernova happened now (well, a month ago) - as far as our frame of reference (and of dinosaurs, or what's left of them) is concerned.

Now it didn't. How far away is the point where the photons got emitted, as measured in our reference frame?

How long time does it take for photons to travel that distance, as measured in our reference frame?

Did the photons get emitted at the time of the explosion?

Re:Dinosaurs? (1)

sznupi (719324) | more than 3 years ago | (#35110076)

The explosion as well as didn't exist for us until now.

Re:Dinosaurs? (1)

Urkki (668283) | more than 3 years ago | (#35110384)

The explosion as well as didn't exist for us until now.

That doesn't change anything. When we observed it, it started to retroactively exist for us. The time for the start of it's existence is the time it took for the light to travel that about 64 million light years. Calculating how many Earth years that is in our reference frame is left as exercise to the reader.

Re:Dinosaurs? (1)

sznupi (719324) | more than 3 years ago | (#35112512)

It didn't exist for us, that changes quite a lot / just now observing something is simultaneity. But the point is ("Or even") - there is no difference, neither way of saying is particularly right or wrong (unless you insist on our locality / I would think we're past Newton by now)

Re:Dinosaurs? (1)

Urkki (668283) | more than 3 years ago | (#35113190)

It didn't exist for us, that changes quite a lot / just now observing something is simultaneity. But the point is ("Or even") - there is no difference, neither way of saying is particularly right or wrong (unless you insist on our locality / I would think we're past Newton by now)

For your information, there's no global reference frame in relativity... We have to pick a reference frame to talk about any events (such as a supernova explosion and humans observing it). And in any reference frame, the event did not happen when we observed the photons, it happened exactly distance/c=time ago. We don't have to pick any particular reference frame, the event still didn't happen "now", so that's always wrong.

Well, you could pick the reference frame of the photons, but I'm not sure that's a valid reference frame anyway, considering that frequency of the EM radiation is infinite in that reference frame...

Re:Dinosaurs? (1)

sznupi (719324) | more than 3 years ago | (#35113582)

How there's no privileged frame of reference, how all of them are equally valid, is the whole point. One which apparently you miss again, insisting on essentially Newtonian time tracking.

Re:Dinosaurs? (2, Interesting)

Anonymous Coward | more than 3 years ago | (#35110228)

My thumb is the size of that car, from my frame of reference. The only way to compare them is to move both of them to the same frame of reference.

Problem is, as I walk towards that car to compare my thumb with it, the car moves away faster than I can walk, so my thumb is getting bigger and bigger all the time.

Sometimes we need an abstract frame of reference. It's no use saying "nothing moves faster than a photon" so we need to be limited to the speed photons can move. What we need to do is move both events to an abstract reference, possibly one in which both events are at rest with its own background microwave radiation, that is they are at rest with the "distant stars".

Then you can say the supernova exploded 64 million years ago.

Re:Dinosaurs? (0)

Anonymous Coward | more than 3 years ago | (#35109050)

What's a million light years between friends?

Re:Dinosaurs? (4, Funny)

Suki I (1546431) | more than 3 years ago | (#35109072)

We will know the real distance when the bang gets here, as long as someone remembered to count when they saw the bang.

Re:Dinosaurs? (1)

Anonymous Coward | more than 3 years ago | (#35109556)

Birds are still around.

Fading more newsworthy than exploding? (2)

sosaited (1925622) | more than 3 years ago | (#35108788)

Interestingly enough, the news of the supernova's explosion didn't made it to Slashdot, but it fading away was more interesting somehow. Kinda like when George W. Bush left the office I guess.

peak visibility (0)

Anonymous Coward | more than 3 years ago | (#35108852)

It maybe would have been more useful if we'd gotten a story when it was at its peak, instead of now?

Slasdot slow as usual (5, Funny)

$0.02 (618911) | more than 3 years ago | (#35108926)

A supernova explodes. Slashdot reports 64 million years later.

Re:Slasdot slow as usual (1)

rubycodez (864176) | more than 3 years ago | (#35109402)

Those with 3 digit IDs tell me Slashdot did report it 64 million years ago, this is just a dupe

Re:Slasdot slow as usual (1)

Sulphur (1548251) | more than 3 years ago | (#35109410)

A supernova explodes. Slashdot reports 64 million years later.

Actually it will be 64 million years May 21.

Re:Slasdot slow as usual (1)

mangu (126918) | more than 3 years ago | (#35110238)

A supernova explodes. Slashdot reports 64 million years later.

64 million years and 29 days, to be precise.

Damn it! (2)

Lotana (842533) | more than 3 years ago | (#35108936)

If only I would of found out about the supernova back in January! Never seen one before and it is possible that there won't be another within my lifetime. At least I can still find this one in the sky before it completely fades.

Obviously Slashdot can't be relied upon to give us up-to-date news. What sites do you use to be notified of non-mainstream events like this as they happen?

Re:Damn it! (5, Informative)

Suki I (1546431) | more than 3 years ago | (#35109010)

Re:Damn it! (1)

Anonymous Coward | more than 3 years ago | (#35111478)

"Devoted to 1962-1979 Chevy II/Novas?" What?

Re:Damn it! (0)

Anonymous Coward | more than 3 years ago | (#35111540)

Stop complaining. It is a .org about Novas.

Re:Damn it! (0)

Anonymous Coward | more than 3 years ago | (#35114102)

Bravo parent. :)

You stupid mods do realize that novaresource.org is a site dedicated to discussions of the Chevy Nova car, right? This would be +5 informative if TFA was about watching a guy's car exploding... from inside a Ford galaxy!

Re:Damn it! (4, Informative)

jc42 (318812) | more than 3 years ago | (#35109046)

If only I would of found out about the supernova back in January! Never seen one before and it is possible that there won't be another within my lifetime.

Don't worry. If you accept supernovas like this one, that's in a different galaxy than ours, there are plenty of them somewhere in the universe every year. It's only if you want one in our galaxy that you have to wait, since the frequency is on the order of one per century.

There was one in the Large Magellanic Cloud back in 1987, easily visible to the naked eye (if you were in the southern hemisphere).

Actually, it's getting to be time we had one in our galaxy. But unfortunately, they don't seem to be scheduled anywhere that we can easily read. The schedule has probably been on file at our local planning department in Alpha Centauri for 50 of our years, but we can't be bothered to make the short trip to check it out. So we'll just have to keep looking up at the night sky until something new appears there.

Re:Damn it! (1)

Maritz (1829006) | more than 3 years ago | (#35110632)

Supernovae in the Milky Way galaxy seem to be less frequent than expected, but this could be explained if lately they've been happening on the far side of the core of the galaxy from us. The concentration of objects there and the dust lanes mean we might not notice a supernova there at all, or we'd have to be lucky and looking in just the right spot at the right time.

Re:Damn it! (3, Informative)

robogun (466062) | more than 3 years ago | (#35109332)

It's not that bright, you need a good telescope to see it. Not that rare either, one hits 12th magnitude once or twice a year. It looks like just another very dim star in the scope. The difference between January and now isn't much at all.

Now, if one were to pop off in our part of the galaxy it would be news. Astronomers have been waiting for one visible to the naked eye for about 400 years.

Here's a list of current supernovae:
http://www.rochesterastronomy.org/supernova.html [rochesterastronomy.org]

Re:Damn it! (0)

Anonymous Coward | more than 3 years ago | (#35109796)

You depend on Slashdot for astronomy news? Seriously? At that rate you'll probably never see so much as an eclipse in your lifetime.

An event like this can't be seen with with the types of equipment that someone who can't be bothered going to an actual astronomy site would own anyway. The kinds of people who own the equipment to make this a worthwhile venture probably spent at least as much on a single eye piece as you did on your latest laptop. And that's assuming you bought something high end.

Re:Damn it! (1)

Anonymous Coward | more than 3 years ago | (#35110386)

Hey, you could always be lucky enough that Betelgeuse explodes sometime soon.

The activity of that big guy has been increasing a lot recently, showing that it could go in to supernova at some point.
But, since we haven't really seen one this huge up close before such a time, we really have no idea if it could explode tomorrow or a million years time.

rhetorical question (4, Insightful)

shadowofwind (1209890) | more than 3 years ago | (#35109028)

When an event is X light-years away, and we're just seeing it now, people speak of the event "having happened" X years ago, on the grounds that it takes X years for light to travel that distance. But how meaningful is it to think of the faraway event as being exactly concurrent with an earthly event X years ago? Light from faraway shows events from when the universe was/is in a less advanced state, so we may try to think of that as the "past". But in a way, for us, those far away events are really "now". There isn't a previous time at which we could witness them without time travel, not even in principle. Furthermore, the thought that "the event really occurred X years ago" seems to assume a universal standard of time, independent of the location and velocity of the observer, by which far apart events can be ordered. But time is not like that is it?

Re:rhetorical question (4, Informative)

Daniel Dvorkin (106857) | more than 3 years ago | (#35109088)

No, it's not; you're absolutely right. In our frame of reference, it just happened recently -- and while you could say, "yeah, but in the star's reference frame, it happened tens of millions of years ago," it's also true that in the star's reference frame, dinosaurs on Earth are just now going extinct. IOW, it's not a very meaningful reference frame from where we're sitting.

The "well, actually it happened X million years ago" comments that seem to accompany every /. story about some distant, recently observed astronomical event are an example of the classic nerd failing of assuming that because we're smart people who know a lot about a lot of things, we're geniuses who know everything about everything. And I'm probably as guilty of it as anyone else ...

Re:rhetorical question (2)

GNUALMAFUERTE (697061) | more than 3 years ago | (#35109274)

almafuerte@almafuerte-laptop:~/Desktop/android-sdk-linux_x86$ ping -c1 slashdot.org
PING slashdot.org (216.34.181.45) 56(84) bytes of data.
64 bytes from slashdot.org (216.34.181.45): icmp_req=1 ttl=241 time=197 ms

Damn! I'm communicating with the past!

Understanding time's true nature and the real effect that nature has on how we experience reality isn't simple. The fundamental question lies in whether we choose to refer to the actual event, or we choose to refer to the information about that event reaching us. Considering that everyday we refer to events happening in the present, when in reality light still takes time to travel any distance, regardless of how small, and therefore everything we experience is the effects of some past event, we should apply a consistent logic when dealing with this situations. Since the event is so far away that treating it as happening now or occurring 64 million years ago doesn't really change anything for us, and given that we find it convenient to refer to past events that happen close enough as "now", we should say that the event has just occurred, instead of pretending that saying it happened 64 million years ago changes anything for us.

Re:rhetorical question (1)

Gaygirlie (1657131) | more than 3 years ago | (#35109340)

and given that we find it convenient to refer to past events that happen close enough as "now", we should say that the event has just occurred, instead of pretending that saying it happened 64 million years ago changes anything for us.

The same logic applies in the reverse too: referring to it as happened 64 million years ago changes nothing for us so it's pointless to pretend it's happening now.

Re:rhetorical question (1)

Gaygirlie (1657131) | more than 3 years ago | (#35109282)

No, it's not; you're absolutely right. In our frame of reference, it just happened recently -- and while you could say, "yeah, but in the star's reference frame, it happened tens of millions of years ago," it's also true that in the star's reference frame, dinosaurs on Earth are just now going extinct. IOW, it's not a very meaningful reference frame from where we're sitting.

I don't understand that. This whole relativity thing sounds really just like bullsh*t, nothing more: if something happened a long time ago but we are only able to see it now, it STILL happened a long time ago. Lacking the ability to see the event doesn't mean the event never happened.

Meh, this whole relativity-bullshit seems like a phase: it's 'cool' and 'hip' to refer to everything as relative and as happening all the time and so geeks are falling over themselves trying to be 'cool' and 'hip' among their peers.

Re:rhetorical question (1)

DigiShaman (671371) | more than 3 years ago | (#35109418)

Maybe, maybe not. But placing events from a relativistic POV can get complicated real fast. The entire concept makes my head hurt. But imagine 2, 3, or more alien civilizations debating on when a galactic event took place. So yes, I agree. I think all events should be referenced at when they actually took place on-site, not when they are taking place from our locality.

Re:rhetorical question (0)

Anonymous Coward | more than 3 years ago | (#35109420)

Don't worry these people are wrong and this is not what relativity says. This is easy to show: If in our frame of reference the light left NOW, travelled 64 million light-years, and arrived NOW, then the speed of that light would be 64 million light-years / (NOW - NOW) = infinity. This would contradict the basic relativity principle that the speed of light is a finite constant c in all frames of reference.

Re:rhetorical question (5, Informative)

Anonymous Coward | more than 3 years ago | (#35109416)

In our frame of reference, it just happened recently

That's not correct. Or at least that's not how simultaneity and past/present/future are defined in relativity, which seems to be what you're referring to with "frame of reference". I suppose you could define 'now' in that way... but that's not how it's defined in modern physics.

In our inertial reference frame, it happened ~64 million years ago. In the star's reference frame, it also happened ~64 million years ago. It's true there is no such thing as a universal reference frame, so one can certainly construct inertial reference frames (e.g. with large velocities relative to us) where the event occurred at different times. Even 'now' (in that reference frame). But the velocity difference between us and the supernova is modest (in the grand scheme of the universe) and thus our two references frames roughly agree about simultaneity and so on.

It's a strange misconception that people interpret relativity to mean that all space-time events on our past light-cone [wikipedia.org] are 'now'. Relativity doesn't say that. It includes a well-defined concept about what is in the past, what is in the future, and the boundary between them being 'now'. We are not immediately aware of all space-time events on the 'now' plane... because it takes time for their signals to reach us. But when we receiving signals we are able to reconstruct and deduce what happened at previous moments. It is true that inertial reference frames do not agree on what 'now' means, and thus don't agree on simultaneity. But within a particular inertial reference frame, there is a meaningful concept of 'now'.

Again, I suppose you could define 'now' in such a way, but it's not at all useful to think of the big bang happening 'right now' as we look far out into space. It makes much more sense to think in terms of it having happened 13.7 billion years ago, and we're only now receiving signals from the afterglow of the big bang from distant regions of space.

Re:rhetorical question (1)

shadowofwind (1209890) | more than 3 years ago | (#35109910)

Again, I suppose you could define 'now' in such a way, but it's not at all useful to think of the big bang happening 'right now' as we look far out into space. It makes much more sense to think in terms of it having happened 13.7 billion years ago, and we're only now receiving signals from the afterglow of the big bang from distant regions of space.

I think whether or not its useful to think of it one way or the other depends on what insight you're trying to gain when you're thinking about it. I also think we can reasonably define "now" any way we want to, as long as we do it in an internally consistent manner and attempt to communicate how we're using the word. Thinking about the big bang as if its in the "past" right here but "now" far away might yield something useful, as something to consider anyway. I really was asking an exploratory question, not just feigning a question as a debating tactic.

Re:rhetorical question (0)

Anonymous Coward | more than 3 years ago | (#35111324)

A good criterion is "how do the equations look when you solve physics problems?" Take for example the speed of an object travelling at uniform speed in a straight line from position p1 to p2, from time t1 to t2. With the "light-cone = past" view, the formula is

v = |p2 - p1| / (t2 - t1).

With the "light-cone = now" view, the formula is

v = |p2 - p1| / (t2 - t1 + c*(|p2| - |p1|))

I don't know about you, but normally when you end up seeing c*|p| added to t everywhere in formulas, it probably means that you're defining t wrong.

Re:rhetorical question (1)

Trogre (513942) | more than 3 years ago | (#35110402)

Can I please be among the first to say: Thank You.

Every time some far away event is reported on /. someone brings up the silly notion that the concept of "happened a long time ago" has no meaning simply because we don't have means to observe the event any earlier than when the light hits us. Currently this is (distance in light years) years after the event actually occurred, but perhaps one day we (sorry, our descendants, definitely not us) might figure out a way to warp space or locate wormholes or some other weird phenomenon now considered sci-fi such that events can be observed closer to when they actually occurred.

Inertial frame velocity (1)

mangu (126918) | more than 3 years ago | (#35110490)

one can certainly construct inertial reference frames (e.g. with large velocities relative to us) where the event occurred at different times

There's the key question: are all inertial reference frames equivalent?

I would say that we do have one preferred inertial frame, which is the one where the background radiation of the universe has zero dipole. Of course, considering the expansion of the universe, this preferred frame is local, but it allows us to define a universal "now" for all practical purposes.

A fact that should be always kept in mind is that relativity has been very useful for accurate calculations in dimensions scaling up to solar system size, but this does not mean it can be extrapolated to infinity. The galaxy rotation problem [wikipedia.org] is one fact that has been showing problems with relativity in the last fifty years. More recently, the Pioneer anomaly [wikipedia.org] shows that our orbital measurements are becoming so precise that general relativity needs corrections.

Science is like that, relativity was good enough until the end of the twentieth century, same as Newtonian mechanics was good enough until the final decades of the nineteenth century. But when measurements become so accurate that they do not match the current theory it's time to move on to a new theory.

These days "dark matter" seems very much like Ptolemy's epicycles, a kludge to force new measurements into the old theory.

Re:Inertial frame velocity (1)

Mindcontrolled (1388007) | more than 3 years ago | (#35114168)

Being preferred doesn't make the reference frame absolute, just useful. That's no contradiction to all inertial reference frames being equivalent. I do agree, though, that the whole dark matter/energy concept seems like a kludge that just cries out for a more elegant theory.

Re:rhetorical question (1)

Khashishi (775369) | more than 3 years ago | (#35109782)

Right idea, but you have the wrong time transformation. The 64 million year figure is probably in our frame of reference. The time is probably calculated by looking at the redshift of the light and applying some model for the universe's expansion. If we see the light reaching us today, that doesn't mean it exploded today. That's not what relativity says. It still happened long ago, but how long ago depends on how fast we are moving relative to the star. We can change how long ago the star exploded by changing our velocity. In fact, the Earth is always changing velocity as it circles the Sun, so the time since the supernova occurred is oscillating. Of course, we aren't changing the past, just how we calculate it. Nevertheless, it happened long ago.

Re:rhetorical question (1)

taara (687286) | more than 3 years ago | (#35109802)

This is, what could be called incorrectly referenced reference frame :) Our reference frame is special, because this is the reference frame we observe things. Why should we choose any other reference frame from multitude of infinite? And in our reference frame the supernova happened about 64 000 000 years ago. I do not understand the confusion here. I could understand the statements though if the person talking does not have insight into special theory of relativity...

Re:rhetorical question (0)

Anonymous Coward | more than 3 years ago | (#35109814)

While I do agree with what you're saying, and article's description superfluous - I do think there is merit in some cases to say that sort of thing. Say, for instance, that one of our most powerful telescopes discovers life on another planet, 100 million light years away.

Yes, in our frame of reference that life-form is alive right now. But if we were to contact them, they would only receive that signal 200 million years later than the time we had just observed on their planet. The chances of that life still existing is rather slim. So for all practical purposes, when it comes to communication with far away bodies, it is worthwhile remembering that it is actually a 100 million years later on that planet than we perceive it to be, and even if we could instantly communicate with them, chances are they're all dead even though it doesn't look that way from our frame of reference.

So my point is just, in some cases that could be a meaningful reference frame.

Re:rhetorical question (1)

Raenex (947668) | more than 3 years ago | (#35109836)

classic nerd failing of assuming that because we're smart people who know a lot about a lot of things, we're geniuses who know everything about everything. And I'm probably as guilty of it as anyone else ...

Re:rhetorical question (0)

Anonymous Coward | more than 3 years ago | (#35111034)

Thought experiment...

The year is 2850. Humans have created wormholes, and these wormholes allow them to effectively teleport from Earth to any region of space where a wormhole has been established. After 150 years of development, the farthest spaceport established is now one light-week from Earth.

A camera at this spaceport constantly beams a signal back to Earth, and one day it records a murder. A week later, when the signal reaches Earth, police jump on the case. Before they run off to investigate, however, a technical consultant at the police department -- who is an ardent Slashdot reader -- informs the investigators that, from their frame of reference on Earth, this murder just happened a few minutes ago, and not a week ago as the police may have naively assumed.

The police exchange perplexed looks, and then teleport to the remote spaceport and begin investigating the spaceport residents.

At the spaceport, nobody seems to recall a murder taking place that day. However, they all clearly recall one from a week ago, and show the police the body. The body matches the one shown murdered in the video, and after taking reports, the somewhat bewildered police take the body and teleport back to Earth with it.

Back on Earth, the police tell the aforementioned technical consultant that he must have been wrong, as everyone on the spaceport agreed that the murder actually took place a week ago. The consultant smiles, and proceeds to explain to the police that this is expected: From the reference frame of those on the spaceport, the murder actually took place a week ago, and only from the point of view of those on Earth did it just take place a few hours ago.

The police are thoroughly confused by this twist of logic, and resign themselves to simply not understanding the mysteries of space and time. Nonetheless, they have a job to do, and so they proceed to take the body down to the coroner. They tell the coroner that they have the body of a man that was just killed a few hours ago, and to look for any clues that may reveal the identity of the murderer. The coroner takes one look at the body and tells the police that they are crazy -- and that this person has clearly been dead for a week, and not for a few hours as the police claim.

And so there lies the conundrum: Who is wrong? (1) The police, spaceport residents, coroner, and the dead guy, who all seem to agree that the event took place a week ago or (2) the educated Slashdot reader who says that, from somebody's point of view, this guy just died a few hours ago?

  The police reason that it must have been incorrect to have assumed that the murder just took place that day from the reference frame of the spaceport, and

Re:rhetorical question (1)

r55man (615542) | more than 3 years ago | (#35111070)

Thought experiment repost... (posted anonymously by accident)

The year is 2850. Humans have created wormholes, and these wormholes allow them to effectively teleport from Earth to any region of space where a wormhole has been established. After 150 years of development, the farthest spaceport established is now one light-week from Earth.

A camera at this spaceport constantly beams a signal back to Earth, and one day it records a murder. A week later, when the signal reaches Earth, police jump on the case. Before they run off to investigate, however, a technical consultant at the police department -- who is an ardent Slashdot reader -- informs the investigators that, from their frame of reference on Earth, this murder just happened a few minutes ago, and not a week ago as the police may have naively assumed.

The police exchange perplexed looks, and then teleport to the remote spaceport and begin investigating the spaceport residents.

At the spaceport, nobody seems to recall a murder taking place that day. However, they all clearly recall one from a week ago, and show the police the body. The body matches the one shown murdered in the video, and after taking reports, the somewhat bewildered police take the body and teleport back to Earth with it.

Back on Earth, the police tell the aforementioned technical consultant that he must have been wrong, as everyone on the spaceport agreed that the murder actually took place a week ago. The consultant smiles, and proceeds to explain to the police that this is expected: From the reference frame of those on the spaceport, the murder actually took place a week ago, and only from the point of view of those on Earth did it just take place a few hours ago.

The police are thoroughly confused by this twist of logic, and resign themselves to simply not understanding the mysteries of space and time. Nonetheless, they have a job to do, and so they proceed to take the body down to the coroner. They tell the coroner that they have the body of a man that was just killed a few hours ago, and to look for any clues that may reveal the identity of the murderer. The coroner takes one look at the body and tells the police that they are crazy -- and that this person has clearly been dead for a week, and not for a few hours as the police claim.

And so there lies the conundrum: Who is wrong? (1) The police, spaceport residents, coroner, and the dead guy, who all seem to agree that the event took place a week ago or (2) the educated Slashdot reader who says that, from somebody's point of view, this guy just died a few hours ago?

Re:rhetorical question (1)

Effexor (544430) | more than 3 years ago | (#35111582)

Well if it was really important why didn't they have someone teleport over to earth to tell people right away? Sending a signal they know will take a week when they could have travelled faster than the speed of light, or even just teleported a message over clearly indicates that they didn't want it solved. I question the lot of them, its clearly a conspiracy. All of them did it, case closed and it didn't take Poirot to solve it.

Wait I got one. A murder takes place in 1 week. A recording is made and sent back in time to police now. They go to 6 days in the future and interview the victim and suspects about the murder that takes place the next day but of course everyone denies any knowledge of it. They take the victim back to the present and give him to the coroner telling saying he's been dead for several hours, no matter what the victim might argue to the contrary. Now, did the victim die in a week, or during the autopsy?

Re:rhetorical question (3, Informative)

jc42 (318812) | more than 3 years ago | (#35109170)

Furthermore, the thought that "the event really occurred X years ago" seems to assume a universal standard of time, independent of the location and velocity of the observer, by which far apart events can be ordered. But time is not like that is it?

Well, yes and no. That can be true for events viewed by observers moving at a sufficiently high speed relative to each other. But this remote galaxy is probably only moving relative to us at a few hundred km/sec, which is a sufficiently slow speed that (for our purposes here) they can be considered in the same reference frame. In such cases, comparing time is simple (though perhaps not doable to nanosecond accuracy).

An example on a smaller time scale: Light moves about 299 792 458 km in a second, and the Earth's diameter is about 12,742 km. So the Earth is approximately 43 light-milliseconds in diameter. Yet it's possible (if not trivial) to synchronize clocks on the Earth's surface to nanosecond precision, and there are communication protocols that keep them synchronized. The GPS system wouldn't work if this weren't possible, and those satellites are moving relative to us even faster than the Earth's surface or this supernova.

One interesting use of this where such precision is critical is that astronomers sometimes combine the data from telescopes scattered around the world to make a large telescope with an effective aperture as wide as the Earth. Doing this requires measuring the arrival time of light waves with precision much better than 43 microseconds. The better precision, the less fuzzy the resulting images are.

This is possible because all those telescopes have very small velocities relative to each other. The max relative speed of two objects on the Earth's surface is twice the rotation speed of a spot on the equator. That's such a small fraction of the speed of light that it's negligible, and they can be treated as being in the same frame to many more than 10 decimal places.

If a remote astronomical object were moving at .99c relative to us, calculating relative times from both viewpoints would be complex and a bit strange to most people. But at relative speeds of .000001c or less, as with NGC 2655 and our galaxy, comparing times to within a few years is simple and straightforward (as astronomers measure such things ;-).

Re:rhetorical question (1)

drooling-dog (189103) | more than 3 years ago | (#35109172)

There's a real question regarding the meaning of "simultaneous" when speaking of events that occur at a great distance. In spacetime, if something happens at a distance of X light-years and no signal or causality can traverse that distance in less than X years, then it may make sense to regard the event as simultaneous with our observation of it.

Re:rhetorical question (2)

mdielmann (514750) | more than 3 years ago | (#35109590)

And this is why simultaneous has a scientific definition [wikipedia.org] . There is a frame of reference where any one of the three options (dinosaurs died first, star supernovaed first, both happened at the same time) is (more or less) correct.

Re:rhetorical question (0)

Anonymous Coward | more than 3 years ago | (#35109372)

Light from faraway shows events from when the universe was/is in a less advanced state, so we may try to think of that as the "past".

That's exactly the right way to think of it.

the thought that "the event really occurred X years ago" seems to assume a universal standard of time

No, it just assumes a local standard of time -- the same one the nytimes uses when it prints a date on a newspaper.

Re:rhetorical question (1)

Lord Ender (156273) | more than 3 years ago | (#35109634)

If our frame of reference were perpetually, immortally static, what you say would be meaningful.

But it isn't. Our frame of reference could change. Therefore, we need to consider a more absolute value for time.

relativity alert! (0)

modmans2ndcoming (929661) | more than 3 years ago | (#35109114)

The star exploded in January, not when the Dinosaur's were around.

Re:relativity alert! (1)

cflannagan (870780) | more than 3 years ago | (#35109388)

The star exploded when dinosaurs were on this planet. If you were in the neighbor of the exploding star (right there when it happens) when it explodes - at the same times, 64 million light years away, we have dinosaurs on this planet. Relativity b.s. It still exploded a LONG time ago - 64 million years ago.

Re:relativity alert! (1)

Anonymous Coward | more than 3 years ago | (#35109626)

you are an idiot.

Re:relativity alert! (1)

Sulphur (1548251) | more than 3 years ago | (#35109390)

The star exploded in January, not when the Dinosaur's were around.

The Dinosaurs left November to become the Birds.

Re:relativity alert! (2)

Urkki (668283) | more than 3 years ago | (#35109812)

The star exploded in January, not when the Dinosaur's were around.

You've got some mighty fast photons then. I mean, just think, how long distance in our reference frame did the photons travel since January? Wow!

Or if you're referring to a January 64 million years ago, I'm sure there are many scientists who'd love to see the math and observations, which let you calculate it was just January, and not for instance Terturary ;-)

Re:relativity alert! (0)

Anonymous Coward | more than 3 years ago | (#35110232)

Let me think... should I believe TFS, or should I believe the guy who doesn't know how to use an apostrophe? (Or, indeed, a capital letter)

Have we ever gotten something better? (2, Interesting)

Anonymous Coward | more than 3 years ago | (#35109142)

Have we ever gotten something better than a few light plates worth of data from an in-progress supernova? I.e. an optical (false color or similar) shot of the thing going off?

It would be fantastic if we could see the shockwave of matter grow and distort. The scale of the explosion should be easily identified but I suppose things may be too hot to image optically with known techniques?

Re:Have we ever gotten something better? (0)

Anonymous Coward | more than 3 years ago | (#35111700)

It's damn too far to image. Even if the shockwave is now 1 light-month wide, the angle is 1 light-month / 64 million light-years = 1.3e-9 radians = 0.00027 arcseconds. Hubble's angular resolution is 0.05 arcseconds.

Re:Have we ever gotten something better? (1)

mrsquid0 (1335303) | more than 3 years ago | (#35111950)

Radio telescopes can resolve sources that are about 0.001 arcsec across, or even smaller in some cases. It may be possible to monitor the expansion of SN2011B over the next few years. In many cases it is possible to watch the shockwave expand into the surrounding medium by measuring changes in the X-ray flux with time. This does not produce a resolved image, but the information can be reconstructed to produce a three-dimensional picture of how the shockwave is interacting with the surroundings.

Supernova Rates (1, Redundant)

mrsquid0 (1335303) | more than 3 years ago | (#35109216)

New supernovae are detected at a rate of about one a day, and that rate will increase as new survey telescopes go online over the next few years. Overall a supernova goes off about once a second somewhere in the Universe.

Sketches? (4, Funny)

ddd0004 (1984672) | more than 3 years ago | (#35109352)

Can't you just get the software they use on CSI Miami and click "enhance" like a million times.

Re:Sketches? (1)

rubycodez (864176) | more than 3 years ago | (#35109674)

that's for w33n0rz, what you really want is the software Decker uses. "track 45 left....stop....enhance!"

Wow Many amateur telescopes (3, Interesting)

Isaac-1 (233099) | more than 3 years ago | (#35109618)

Translation, it is photographically within the reach of telescopes costing only a couple of thousand dollars, and from a good dark sky location visually within the reach of telescopes costing about as much as a typical reasonably nice used car (that is as a very dim pinpoint). The number of amateur telescopes in the world that can provide a decent view of this object is probably fewer than the number of people that will end up posting in this message thread.

Re:Wow Many amateur telescopes (0)

Anonymous Coward | more than 3 years ago | (#35109732)

"The number of amateur telescopes in the world that can provide a decent view of this object is probably fewer than the number of people that will end up posting in this message thread."

Your thread seemed lonely (but you may still be right: ))

Re:Wow Many amateur telescopes (3, Informative)

martinux (1742570) | more than 3 years ago | (#35110602)

Magnitude 12.9 is quite visible to a 254mm (10 inch) newtonian (dobsonian) telescope that would cost you less than $600 if you picked one up second-hand. The trick is familiarising yourself with the night sky to be sure you're looking at the correct dim dot. ;)
For thousands of dollars (and a lot of patience) you can discover them yourself using a computer controlled mount and a modest amount of aperture: Dave Grennan *discovered* a supernova from the outskirts of Dublin city using a 14 inch Cassegrain scope. http://www.science.ie/science-news/supernova.html [science.ie]

https://secure.wikimedia.org/wikipedia/en/wiki/Limiting_magnitude#In_amateur_astronomy [wikimedia.org]
Magnitude calculator: http://www.cruxis.com/scope/limitingmagnitude.htm [cruxis.com]

If only we could get more done about the horrible light pollution one wouldn't have to travel so far from urban areas.

Re:Wow Many amateur telescopes (1)

Isaac-1 (233099) | more than 3 years ago | (#35110750)

I don't know if I would go with quite visible in a 10 inch newtonian, maybe under near ideal skies it is faintly visible to experienced observers using averted imagination. By comparison for the type skies accessible within a couple of hours or driving time to the majority of the U.S. population and to clearly see an object of this brightness as something more than a faint cloud that one questions if they ever saw in the first place it would likely take a well built telescope of at least 15-18 inch size range, the cheapest on the used market being a dobsonian in perhaps in the price range of a couple of thousand dollars, with new prices well above that. Perhaps in my original message I was being optimistic about the number of replies this topic would get, but think the point remains basically true.

Re:Wow Many amateur telescopes (2)

martinux (1742570) | more than 3 years ago | (#35110880)

The illustration (in TFA) of 2011b was made with one of these (visually, of course):
http://www.pulsar-optical.co.uk/prod/telescopes/sky-watcher/dobsonians.html [pulsar-optical.co.uk]
(Please note I have no affiliation with the above company)

As for seeing it as a faint cloud: What more do you want? Consider the image taken of supernova 2010 IK:
http://cdn.thejournal.ie/media/2010/10/supernova1-478x377.jpg [thejournal.ie]

You're looking at something that's 290,000,000+ years old. Even a faint fuzzy is enough to appreciate the fact that light had to travel a somewhat lengthy distance to get to one's eye. I think a major problem with amateur astronomy is the unrealistic expectations of many newcomers. Images from professional observatories (including space-based telescopes) show large images with significant detail - some consider this to be 'what you see through a telescope' and don't think too much about the nature of the telescope in question.

Educating people in what they're looking at and why it's so small goes a long way to improve their appreciation of the detail one can see through even a small telescope. :)

Re:Wow Many amateur telescopes (5, Informative)

Kentari (1265084) | more than 3 years ago | (#35110942)

Photographically it is well within reach of DSLRs equiped with a 200mm lens. I managed to go down to magnitude 17 (or 100 times less bright) and even fainter with a Canon 20D and a 200mm f/2.8 lens, placed on a tracking mount and exposed for about 2 hours (accumulated in exposures of a few minutes). I'm sure it would even lie within the limits of a 50mm lens. The problem becomes distinguishing it from the host galaxy.

Visually it was within reach of 4.5" beginner scopes at dark locations! These will set you back less than $200 nowadays. A $1000 12" would have produced very decent views of the SN together with it's host galaxy. There are a lot of telescopes of this size around. You obviously should take the time to visit a public observatory once.

WOW (0)

Anonymous Coward | more than 3 years ago | (#35110416)

Are you Guys saying that we can see this right now? If that is the case then I would LOVE to ...Think about this guys...Its only going to be this ONE time in your LIFE that you can see this and then after that who knows when it will happen where we can see it agine....!!!! I think that this is GREAT and we should all step back from the Computers and games and Take a look at how the Universe works....Bebe.

More images of 2011B (1)

Anonymous Coward | more than 3 years ago | (#35111186)

I created a web page to archive 2011B images:
http://www.RochesterAstronomy.org/sn2011/sn2011b.html

If you would like to take a look at some other current supernovae:
http://www.RochesterAstronomy.org/snimages/index.html

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