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New Supernova Seen In Nearby Galaxy M82
The Bad Astronomer writes "A new and potentially bright supernova was just discovered in the nearby galaxy M82. This is a Type Ia supernova, the catastrophic explosion of a white dwarf. It appears to be on the rise, and may have been caught as much as two weeks before peak brightness. It's currently already brighter than magnitude 12, and may get to mag 8, easy to see in small telescopes. The galaxy is less than 12 million light years away, so this may become one of the best-studied supernovae in recent times. Type Ia supernovae are used to measure dark energy, so seeing one nearby is a huge boon to astronomy."
I love Astronomers ... sure, 12 million light years away can be construed as 'nearby' on some scales.
Obviously galaxies tend to be a little further away, but it's definitely a relative use of the term 'nearby'.
Having said that ... go science! This is pretty cool.
Lost at C:>. Found at C.
Just sayin'.....
It was a long time ago in a galaxy far, far away.
And yes, many Bothans died to bring us this information.
It was a Trap!
A feeling of having made the same mistake before: Deja Foobar
Since no information can travel faster than light, for all intents and purposes and discussions of causality it is happening right now. Since we are just entering its light cone, anything outside of it is inaccessible to us - and always will be.
> I'm always stressing to people at our star parties the light you see is history.
I'm surprised they still invite you. They probably already know.
The galaxies M81 and M82 are only about 300K ly from each other. A decent telescope can image them both at the same time. Relatively easy to find in Ursa Major too. I look forward to viewing this during the next new Moon.
Technically, everything you ever perceive is in the past. More often than not, two simultaneous perceptions of the same thing are not even the same past.
How brains manage to correct for both the perception latencies and the action latency, so that we can interact with our environment, is pretty amazing.
Except, in our frame of reference, it's happening now, even though it happened then.
Which means in the future, we will would have seen this from before, but we won't have yet known if more stuff which will would have happened in the past will be happening in the present as the future unfolds.
So it is simultaneously not happening now, and happening now -- it isn't really happening now there, but here it is happening now, except it already happened there, and technically it has already happened here, but we're only now becoming aware of it now, but in the future, both will have happened in the past.
Which is why we stick with tenses which make sense to our poor little brains. it's just too damned hard to conjugate the verbs. ;-)
So, from what I've been able to tell -- we discuss it in the present tense, and then occasionally remind ourselves that we're seeing something which happened a long time ago. But then we try not to mix up the two, because it hurts more than an ice-cream headache.
Lost at C:>. Found at C.
No boom today. Boom tomorrow.
Always boom tomorrow.
Lost at C:>. Found at C.
THE question I am sure many will think about is how many neutrinos will be detected.
For supernova 1987a at 168'000 light years 24 neutrinos have been detected.
At 12 mega light years M82 is 71 times further, which dilutes the neutrinos by a factor ~5000.
So the answer is 0 neutrino if the detectors were the same as in 1987.
I doubt that the present detectors have improved by a factor 1000 in the meanwhile,
but I would be glad to be disproved.
White dwarf? The inhabitants had long since resettled, if they knew about themselves.
The sad nature of the universe is that untold numbers of unique lifeforms have been summarily extinguished by the the deaths of their stars for billions of years.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
The information is new to us. Take your meds.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Thank you, Dr. Streetmentioner.
When will then be now?
I can't see through a monocular eye piece, you insensitive clod. ;-)
Actually, that part is true ... when I try to look through a telescope eye-piece all I see is a blob, but strangely, I can see through my DSLR (which seems to have a larger eyepiece than most telescopes do). But I've literally never seen anything through a telescope, which kinda bums me out, because I'd like to.
I strongly suspect that means I'm either an idiot, or looking through the wrong end of the telescope. Of course, the latter could be a symptom of the former.
Lost at C:>. Found at C.
only here 12 million light-years could be implied to be near ^^
Except, in our frame of reference, it's happening now, even though it happened then.
Nope. In our frame of reference, it most definitely happened then. The light is reaching us now. It's too late to emit a beam of light of our own to meet the supernova light halfway, which it wouldn't be if it was happening now.
The only reference frame at this point in space in which it is happening now is that of the light which is reaching us.
systemd is Roko's Basilisk.
Supernovas can affect the biospheres of planets within eight parsecs
Still, that's nothing compared to the hypothetical death tolls in active galaxies.
Optical devices, such as cameras with optical viewfinders, telescopes and binoculars are designed to to be used with the eye a certain distance away from the eyepiece's lens. This distance is known as "eyepoint", and pesons wearing eyeglasses often have difficulty using "low eyepoint" devices.
Since no information can travel faster than light, for all intents and purposes and discussions of causality it is happening right now. Since we are just entering its light cone, anything outside of it is inaccessible to us - and always will be.
Well, if you argue that, you have to give up concept of distance, or concept of speed of light. From our frame of reference, light traveled certain distance at certain speed, and simple calculation will tell how long time it took.
Or to put it another way, when you receive reflection of light you sent to a mirror, neither sending nor reflecting happened when you received the reflection back. It is in fact possible to determine distance of mirror by knowing how long ago sending and reflecting happened.
It's currently already brighter than magnitude 12, and may get to mag 8, easy to see in small telescopes.
That's a pretty optimistic statement given the rampant state of light pollution around the world!
The naked eye limit is Mag. 3 for most of us who live near any streetlights. Magnitude 8 objects require a 6-8" telescope, preferably with tracking if you want to find the Mag. 8 galaxy.
I don't think of telescopes above 4" as "small."
I type this not to be annoying, but because a lot of people are going to waste a lot of time at night trying to see this thing when it is likely beyond their equipment (or patience) limit.
Over such distances the expansion of space is totally insignificant -- that's a large scale effect and is *only* active on large scales. Local structures are totally disconnected from it. (If the language doesn't sound intimidating, the expansion is a feature of the Robertson-Walker metric, which is assumed to be valid on very large scales. It is not a feature of Schwarzschild, Kerr, Lemaitre-Tolman-Bondi, Szekeres or other metrics that describe smaller structure, although it's true that you can find, say, an LTB that also has a cosmological constant. Since local structure will be described by something close to a Szekeres, it is not influenced by the "universal" expansion.) It's a bit like the universe is that old expanding rubber sheet, and local structures are pebbles rolling around on it. The pebbles aren't growing, even though the space between them is.
Extra points for anyone spotting an enormous logical flaw in this picture that is at the heart of one of cosmology's biggest (and unsolved) fundamental issues.