Possible Supernova In Nearby Spiral Galaxy

New submitter Zburatorul writes "In an electronic telegram to the IAU, an Italian astronomer reports his discovery of a possible supernova (magnitude R = 15) near spiral galaxy M95 on images taken March 16th. Many more independent and confirming observations are trickling in. The Bad Astronomer, Phil Plait, has a more layman-friendly article about it. The bad news: it won't be visible with the naked eye. The good news: it's not going to kill us."

SN2012aw is ready for its closeup

[The Bad Astronomer]

I've received some nice pictures of the galaxy+SN which I just posted to the blog as well [discovermagazine.com]. Looks like this is a Type II, the explosion of a massive star at the end of its short life.

Re:Relativity

[Kreigaffe]

Huh?

It happened ~40 million years ago. We're just now seeing it.

Not a hard concept, not even relativity really. Go outside, see a gunshot from a great distance (or, well, anything else loud). You'll see it before you hear it. At such relatively short distances, light takes very little time to reach your eye, but sound takes much longer. Now increase the distance, and light takes a long time too. Bam.

why would we think it was going to kill us?

[Xtifr]

If Betelgeuse, very much in our galaxy, and quite visible to the naked eye even before it goes supernova, is no threat (and it's not, though it could go supernova any time in the next million years), why on Earth would we be worried about an explosion in another galaxy?

Supernova occur (and are observed) fairly regularly. The estimated rate of supernova production in a galaxy the size of the Milky Way is about one every 50 years. We know of millions of galaxies. It's always nice to catch one as it's occurring, especially one as close as this, but the summary is just ridiculous.

Re:Quantum Mechanics {Re:Relativity}

[dissy]

Well, according to the most popular view of QM, a wave function doesn't collapse until an observation is made. So unless there are alien species that live closer to it and watch the skies, it has spent the last 40My in a superposition of "went nova" and "didn't go nova". So in some sense it "happened" just now.

No not quite. The word is "measurement" not "observation".
Once the photon gets absorbed by Anything, it has been measured, or as you call it "observed". This can be a spec of dust floating in space, or a bit of rock or gas on a dead world. It could be next to anything that absorbs that photon to collapse its wave, and that something does not need to be alive or conscious or more than just a simple little atom of hydrogen.

Also with relativity you can not use "when something happens" alone as a metric. No such thing exists. The question is "when something happens, from what point of view"

From the stars point of view, yes it happened long ago and our part of the universe is just now being affected by it and seeing it.
From our point of view, the light just made it here, so it just happened.