2020, AAVSO, American Association of Variable Star Observers, astronomy, astrophysicist, astrophysics, Betelgeuse, constellation, Orion, Star, stellar, Summer, supernova, supernovae
The star Betelgeuse is doing something. Something important. No one is sure what it means, but it has our attention and we want to keep our telescopes focused on it. Except that this Summer, we can’t.
Whatever is happening with the soon-to-be supernova Betelgeuse currently, it is critical astronomers and astrophysicists maintain close observation of the progenitor star. It may be decades, centuries, or millennia before it collapses and explodes into a spectacular show for our planet nestled some 640 lightyears away, and yet, at this moment, it is displaying behavior that may give us the first opportunity to learn what a supernova does before it does its supernova thing.
Betelgeuse and its parent constellation, Orion, are victims of the Earth’s orbit around the Sun. For two months in the Summer (approximately Cinco De Mayo to Independence Day in the U.S.) the constellation is on the opposite side of the Sun from Earth. Astronomers will not be able to see the star at a time that may be crucial to understanding pre-supernova behavior.
Betelgeuse is a variable star that is undergoing a historic expansion, cooling, and dimming (fainting) phase. That process is likely near the end. Next up should be a contraction, warming, and brightening phase. That process will take months…right into Summer. When the curtain drops on Betelgeuse in May, Earth-bound astronomers and astrophysicists will be an audience without a show to watch.
There are multiple possibilities for what might happen. Betelgeuse might increase in brightness over several weeks or months as it has in the past, then resume a normal cycle. It might brighten, but not to the magnitude it has in past cycles. The star might keep brightening to a greater magnitude than it has in the past. Betelgeuse might also brighten suddenly and begin its short-lived supernova phase. No one knows.
What is known is that astronomers will be observing Betelgeuse as long as possible. We will know if something major happens this Summer through other electromagnetic observations and non-Earth bound observation sources, but for amateur astronomers, we will have to wait and not see.
Dan Loeb said:
Do you think any deep space probes will have their cameras turned that way? Even satellites in near earth orbit can look at Betelgeuse as long as it is not directly behind the sun.What alternatives would be available in that case?
Paul Kiser said:
Dang it! I intentionally avoided that topic so I wouldn’t have to admit that I don’t know. 😁
Seriously, I am out of my league on that question. I don’t know the current inventory of Earth’s space observational platforms nor their flexibility to keep an occasional eye on Betelgeuse. A professional astrophysicist would be able to address this question.
I’m confident that if Betelgeuse began exhibiting more unusual behavior, resources would be put into play to observe and record it but that would involve reprioritizing the existing mission and I have no idea what that would involve.
I have to believe that we currently have the capability of tracking the apparent magnitude of Betelgeuse, even during the Summer gap. Unfortunately, for amateur astronomers, we are limited by our ride as to what we can see and when we can see it.