2878: Supernova

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Supernova
They're a little cagey about exactly where the crossover point lies relative to the likelihood of devastating effects on the planet.
Title text: They're a little cagey about exactly where the crossover point lies relative to the likelihood of devastating effects on the planet.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by THE NEAREST STAR GOING SUPERNOVA (YES THE SUN) - Please change this comment when editing this page. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.
Supernovae are catastrophic events in which a heavy star collapses and then explodes when its fuels runs out and it can no longer produce enough energy to fight it's own gravity.

These are some of the most interesting events for astronomers to observe, and they can use them to glean information about the universe.

The further away they are the less details can be learned from them and thus this will not make the astronomers as happy as if they where closer by. Many astronomers began their career choice because the enjoyed watching the stars in the night sky. And the ultimate astronomical even to observe with the naked eye, would be a super nova explosion in our own galaxy the Milky Way, preferably clearly visible from Earth.

One such supernova candidate that has been mentioned a lot lately is Betelgeuse, a red giant that draws the top part of the left shoulder in the constellation of Orion, and the star is located about 430 light years from the Sun. It has been pulsating, dimming and brightening over short time scales, compared to the tens of millions of years such a big star is expected to burn. There could easily go several thousand years before it goes supernova, but it could also already have happened, and we are just waiting for the light to reach Earth. And it will go supernova! Betelguese should be far enough away from Earth that it would be safe enough for life on Earth (See for instance Is Earth in danger if Betelgeuse goes supernova? where Astronomer Patrick Moore answers: No to the question).

But if a Super Nova gets closer than say 100 lightyears the supernovae might be too close, then the effects could destroy life on earth, so obviously astronomers and everyone else would be really unhappy, as indicated by the sudden drop far below the scale on the graph.

The title text expands upon the latter point of nearness, in that it is not certain that the point at which it is close enough to destroy (or be devastating) to Earth, and the astronomers themselves, is the point at which an astronomer would actually trip into the 'unhappy' part of the graph (presumably below the x-axis). The chance to witness even a lethally-close supernova might still be an attractive proposition for some inquisitive minds.

Transcript

[A graph is shown where the axis are labeled and arrow are pointing up above the Y axis label and to the right above the X axis label. There is a single line on the graph which peaks close to the Y axis, where it reaches close to the top of the drawn part of the Y axis. Then the lines approaches the X axis asymptotically towards the far right. But closer to the Y axis than the peak line goes almost vertically down, and continues far below the "bottom of the chart", that was only supposed to be above the X axis.]
Y axis: How happy astronomers are
X axis: How far away the new supernova is


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Discussion

It's all fun and games until the supernova is 93 million miles away Poxy6 (talk) 13:03, 8 January 2024 (UTC)

Luckily there's only one star that close, and it's not big enough to become a supernova. "when our Sun runs out of hydrogen fuel, it will expand to become a red giant, puff off its outer layers, and then settle down as a compact white dwarf star" [1]. Of course, that will still destroy the Earth. Barmar (talk) 16:33, 8 January 2024 (UTC)
"...there's only one star that close at the moment!". ;) Ok, so we haven't seen anything likely to swing by close (any time soon), never mind being in an explody frame of mind whilst doing so, but... :p 172.71.178.61 16:41, 8 January 2024 (UTC)
Alpha Centauri is very nearly identical to our sun. It will also go red giant and then explode.Nitpicking (talk) 16:53, 8 January 2024 (UTC)

This seems to be a very early release. I had not expected to find a new comic already. Maybe Randall knows Betelgeuse goes Super Nova today... He can't wait - see 1644: Stargazing! Unless of course it is too close! (Betelgeuse should be a safe distance away and seems by far the closest Super Nova candidate, as least according to Astronomer Patrick Moore). --Kynde (talk) 13:07, 8 January 2024 (UTC) I added an explanation and transcript 172.70.43.108 13:09, 8 January 2024 (UTC)

I wonder if randall has played outer wilds 172.70.178.53 16:34, 8 January 2024 (UTC)

I recall other proximity chart comics about 'how close people are to things' such as proximity to cats. Maybe someone can find those and add them as references. Laser813 (talk) 16:40, 8 January 2024 (UTC)

I'm feeling lazy and not feeling like verifying this, but I think the graph is also representative of the light curve we expect to see during a supernova. The stars brightness reaches a peak very quickly, then more gradually diminishes. Galeindfal (talk) 18:04, 8 January 2024 (UTC)

Exactly, I thought this was the joke: The graph under the title "Supernova" looks just like a Type Ia supernova light curve, but then it turns out to be about enthusiastic astronomers. It seems supernovae aren't only helpful in establishing a distance scale to astronomers, but also to behavioural scientists who study astronomers. Transgalactic (talk) 20:55, 8 January 2024 (UTC)
even a superficial search by a behavioural scientist (who also handle statistics :) makes this aspect obvious. Absolutely worth to integrate it into description! https://www.ecosia.org/images?addon=opensearch&_sp=32592cb2-9564-46eb-9b5c-5ae955333b74&q=supernova+graph --LaVe (talk) 00:57, 9 January 2024 (UTC)

Why the fuck aren’t the units and magnitude of the axes labled? I had to use my brain. 172.70.207.89 05:28, 9 January 2024 (UTC)

Surely there should be some dotted sections, particularly the gap between the edge of the Milky Way and Andromeda, then the next nearest galaxy (where there are few stars)? RIIW - Ponder it (talk) 08:33, 9 January 2024 (UTC)

Anyone know of a recent event that could have inspired this comic? Betelgeuse is mentioned in the explanation but has there been any newsworthy supernovae in the past week? Alcatraz ii (talk) 05:49, 9 January 2024 (UTC)

Maybe this? 172.70.210.40 12:31, 9 January 2024 (UTC)
Oh yes! Transgalactic (talk) 21:43, 9 January 2024 (UTC)

isn't the chart missing an uptick to the right? wouldn't the appearance of a supernova at, say, 13.6bn light years away make astronomers extremely happy? --172.70.91.211 15:40, 9 January 2024 (UTC)

The shape of the graph is very similar to 815: Mu guess who (if you want to | what i have done) 17:49, 9 January 2024 (UTC)

That one's decline is much flatter. Transgalactic (talk) 21:43, 9 January 2024 (UTC)

No. It could not have already exploded. This indicates a lack of understanding of relativity. The more accurate statement would be that from our perspective, Betelgeuse hasn't exploded yet, and from the perspective of Betelgeuse, Earth is as it was 700 years ago (local to earth), and from the midway point between Earth and Betelgeuse, Earth is as it was 350 years ago (local to earth) and Betelgeuse is as it was 350 years ago (local to Betelgeuse). Simultaneity changes with the perspective of the observer. 172.69.22.51 (talk) 18:44, 9 January 2024 (please sign your comments with ~~~~)

It is, however, possibly at the stage of "though we do not yet know it, we are to experience the signs of it having happened prior our own current time" (as in broadcasting "have you exploded yet?" would not have been answerable before it actually does, even if we somehow managed to do so several hundred years ago). But rewrite it as you see fit. I can see why the author of the current version decided not to go into that, and why you might be put off from trying to give the "more correct" version an airing through your own edit... 172.70.91.11 19:02, 9 January 2024 (UTC)
It would be more of an edit than a re-write, as the statement should simply be struck. It is incorrect to say that what we see 300 LY away occurred 300 years ago. We simply have a view of spacetime based on our relative position that, should that position change with respect to Earth and Betelgeuse, would mean different simultaneity (not just from a light perception perspective, but when it comes to causality in general). If it helps, then I'll go in and remove the errant phrase.

I just redacted much of the explanation because it was riddled with repetitions, errors and scientific imprecisions. (I didn't elaborate on the relativity issue, though, just added "locally" to that sentence.) I Hope you appreciate the result. Transgalactic (talk) 21:43, 9 January 2024 (UTC)