Editing 2878: Supernova

{{incomplete|Created by A CAGEY ASTRONOMER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

{{w|Supernovae}} are catastrophic events in which a heavy star collapses when its original fuel runs out and it can no longer produce enough energy to fight its own gravity. The collapsing mass leads to a violent explosion, one of the most interesting events for astronomers to observe and one that can be used to glean information about the universe.  

This comic shows a graph that displays, in general terms, how happy astronomers would be when they discover a new supernova based on how far away it is from Earth. The further away one is, the less detail can be learned from it, and thus the less happy astronomers are. But a supernova closer than, say, 100 light years might be ''too'' close. Its radiation could destroy life on Earth, or at least significantly harm the biosphere. Astronomers (and many others) would be really unhappy if that happened, as reflected by the sudden drop in happiness to far below the X axis on the graph for a supernova that is too close.

Many astronomers watch and study the stars in the night sky, even the ones that don't change appreciably over human timescales, but observing and recording such a huge event would be interesting for many reasons. Even if not directly involved in the science, humans can observe some supernovae with the naked eye, especially if they occur within {{w|Milky Way|our own galaxy}} and are clearly visible from Earth. A potential supernova in the news lately is {{w|Betelgeuse}}, a {{w|red giant}} star that is the left shoulder in the constellation Orion. About 430 light years from the Sun, it has been pulsating, dimming and brightening over exceedingly short time scales compared to the tens of millions of years such a big star is expected to burn. Though it could yet easily go several thousand years before it goes supernova, it could also already have exploded and we are only waiting for the light from the event to reach Earth. Betelgeuse should be far enough away from Earth that the inevitable explosion would be safe enough for life on Earth (although [https://www.skyatnightmagazine.com/space-science/earth-danger-betelgeuse-supernova some assessments] are not so sure), but it ''will'' outshine all other stars in the night sky, possibly competing with the Moon, and could even be visible during daytime. This would be a dream come true for many astronomers and something obvious to others interested in the night sky. In the first [[:Category:Stargazing | Stargazing]] comic, [[1644: Stargazing | 1644]], the wish that it goes supernova (in [[Randall|Randall's]] lifetime) is clearly expressed.

Since this ''should'' be safe for us, and since it would be a spectacle not seen for hundreds of years here on Earth, this would make the astronomers very happy, not just from all they could learn, but also from just from all the increased interest in gazing at the sky with the 'new' star (and then seeing what happens to it next).

A distance exists where the astronomers would be the most happy, with anything nearer than that being less good (or very bad). As more distant phenomena only decrease the positive effects (and certainly do not increase the bad ones), the graph beyond the maximum happiness appears to show an asymptotic approach to less and less positive influence on the mood of the astronomers. There are thought to be about three supernovae occuring per century within our own galaxy (most stars of which are far further away from Betelgeuse), and many other nearby and far more distant galaxies within which a supernova explosion can be detected. These remain useful to see, and are often studied as intensively as possible, but have decreasing amounts of thrill to them and are harder to notice/record in the early stages of the explosion (or immediately before, to add even more understanding).

The title text expands upon the latter point of nearness, in that the astronomers themselves are not quite clear/unwilling to admit how close they would like a supernova to be. If it were close enough to destroy Earth or instantly kill of all life on Earth, they would presumably not be happy. But they might actually be willing to accept some trouble for Earth life if they get to the see a supernova comparatively close by. But the chance to witness even a {{what if|73|lethally-close}} supernova might still be an attractive proposition for some inquisitive minds. At least it is expected that they require time to realize they are seeing (or are about to see) a supernova before it kills them, to become ecstatically happy about it!