Not because I’m particularly gloomy (according to my friends and family, I’m actually more of a goof), but because they are fabulous ways to illustrate the workings of the universe.
They are also great for making you appreciate the delicate set of contingencies that allow us to exist right now, right here on Earth.
That means it has begun nuclear fusion of helium in its core, creating oxygen and carbon and starting down the pathway to core collapse and eventual supernova detonation.
Exactly how long it will take for that full process to happen is unknown; researchers can make only approximate estimates using models of stellar evolution.
That’s about 150 times as far away as Alpha Centauri, the nearest star system.
Even at the low end of the distance estimates, Betelgeuse is too far away to do significant damage to Earth.Some of the scenarios are so unlikely that they are hardly worth considering–for instance, a stellar-mass black hole barreling straight toward our solar system.But there’s one disaster that falls into the sweet spot.Fortunately (or unfortunately, if you are hoping for some really exciting destruction), our Sun will not, can not ever explode as a supernova. No nearby star is a supernova candidate either–not surprising, since stars massive enough to go supernova are few and far between.The closest likely candidates are two bright red stars that are both prominent in the sky, and that are both coincidentally rather similar in distance: Antares in the constellation Scorpius and Betelgeuse in Orion.It’s possible they caused a period of climate cooling, but it’s also possible that the changing climate was completely unrelated.At any rate, there was no mass extinction during that era.Now, let’s look at that other term, “close.” It’s not so easy to measure the distance to a bright red giant star like Betelgeuse.Different methods give answers ranging from 520 light years to nearly 700 light years.Material ejected by the Betelgeuse supernova will have expanded and cooled to insignificance long before it reaches Earth.Radiation from the Betelgeuse supernova will certainly have some measurable effects on Earth’s environment, but probably only a minor impact on life.