Monday, January 6, 2020

Stay strong, Betelgeuse -- stay strong!






































image: Wikimedia commons (link).

If you haven't seen the news already, the web is abuzz lately with the observation by astronomers who monitor the brightness of certain stars that the red "super-giant" star Betelgeuse has suddenly and somewhat unexpectedly dimmed over the past few months.

According to certain specialists who focus on observing Betelgeuse, the star is known to be variable in its brightness, going through fairly predictable cycles of dimming and brightening, but this latest dimming is unprecedented in that the star has dimmed more than at any time in the past hundred or so years that its relative brightness or dimness has been measured using objective instrumentation to measure and record Betelgeuse's magnitude.

Here are several recent articles on the web discussing the sudden dimming of Betelgeuse, including one which features some interview segments with astronomer Edward Guinan on NPR ("National Public Radio," in the united states), in which you can listen to the interview as well as read the transcript:
Most of the stories linked above contain very much the same information, but each provides a few different details to help give a fuller perspective if you visit them all (each is relatively short).

One theme that is present in many of the articles is the breathless anticipation, sometimes expressed as a positive hope, that this sudden dimming presages the inevitable collapse and massive explosion of Betelgeuse into a supernova, ending the star's life in its present form. 

Such an event would create a spectacular cloud of colorful gas and plasma in the sky, so bright that it would rival the brightness of the full moon during hours of darkness (bright enough to cast shadows on earth during the night, as during a full moon, which is so bright that you can typically read a book under the light of a full moon on a clear night) and even be visible during the day. But the familiar Betelgeuse in the constellation of Orion would be gone forever in its present super-giant form.

Some of the articles above quote first-year graduate student in astronomy at UC Berkeley Sarafina Nance expressing her hope that Betelgeuse will go supernova during our lifetimes, while noting that she and other astronomers are quick to point out that although they expect Betelgeuse to collapse and explode at some point in the next hundred thousand years or so, there is no way of knowing when that might take place. Nance is quoted as saying:
Disclaimer: I don't think it's going to explode anytime soon. But I am excited [for] when it does. It would be so incredibly cool! By far and away the most incredible event to happen in my life.
That interview with National Geographic is cited in the National Geographic article above.

While it would of course be a spectacular and exciting event, I for one very much hope that Betelgeuse will not collapse and explode anytime soon, and send these words of encouragement to the star: "Stay strong, Betelgeuse!"

Betelgeuse forms the important "shoulder star" of the constellation Orion, one of the most recognizable (probably the single most-recognizable, in fact) constellations in the night sky. The constellation contains the highest ratio of bright stars to total stars of any constellation, and includes the brilliant belt of Orion, three second-magnitude stars in a nearly (but not perfectly) straight line, familiar to nearly everyone on earth, and has a beautiful hourglass-like symmetry that would be forever altered should Betelgeuse explode.

Betelgeuse can be seen in the image below as the star in the "upper left" of the hourglass-shaped outline of Orion as we face the photograph:

image: Wikimedia commons (link).Here is what H. A. Rey has to say about the constellation and its stars, from his indispensable book The Stars: A New Way to See Them (first published in 1952): 
Superb constellation. When Orion is up he dominates the southern sky, you can't miss him. His most striking part is the BELT, three bright stars in a straight row; you can easily trace the rest of the constellation from there. -- A hunter by profession, Orion is heavily armed, with a raised club, a shield, and a sword dangling from his belt [note that the upraised club and extended shield, sometimes envisioned as a bow, are not shown in the image above]. No other constellation has so many bright stars, five of 2nd mag. and two of 1st mag.: reddish BETELGEUSE in the left shoulder, and bluish-white RIGEL in the right foot. Rigel is a giant star, 33 times the diameter of the sun and 20,000 times as luminous, over 500 light-years away: what you see in the sky these nights is light which left the star before Columbus was born. Betelgeuse is a supergiant, 400 times the sun's diameter, 3600 times as luminous, about 300 light-years away [note that in the articles cited above, astronomers now appear to have revised this estimate for the location of Betelgeuse to between 640 to 724 light-years away]. One of the stars in Orion's sword looks slightly fuzzy; field glasses reveal a hazy spot around it: the GREAT ORION NEBULA, a luminous gas-cloud, extremely thin but so vast that 10,000 stars the size of our sun could be formed from its mass. It looks so small because it is 300 light-years away. 46
Orion in its present form is a familiar figure and an extremely mythologically-important constellation, and I for one am not desirous of seeing its outline radically altered forever, despite the fact that witnessing a brand-new supernova (from a safe distance) would certainly be, as Sarafina Nance says, "so incredibly cool!" Of course, as many of the articles above point out, and as H. A. Rey himself explains in the above-cited paragraph, when he is talking about the light from the star Rigel, because Betelgeuse is hundreds of light-years away (now thought to be between 640 and 724 light-years away), this means that by the time anyone on earth sees the explosion of Betelgeuse, that supernova event would have actually begun at least 640 years earlier. So it may be that it has in fact already taken place, and we are still just waiting to see it -- but I personally hope not.Orion plays vitally-important role in many of the world's ancient myths, including in the widespread memory of a lost "Golden Age," which the authors of Hamlet's Mill appear to have equated with the Age of Gemini (see discussion in an early blog post here from all the way back in 2011) and which they associate with the world-wide myth pattern of a benevolent god who comes to live among mortal men and women for a time, teaching them important civilizing skills, before leaving again -- often to sleep beneath the sea (such as in the stories of the god Saturn sleeping beneath the waves in the cave of Ogygia, which is also related to the fate of King Arthur sleeping an enchanted sleep beneath the surface of the lake).This pattern of a benevolent ruler going down beneath the waves, the authors of Hamlet's Mill appear to argue (although their explanation is enhanced and clarified a great deal by the later work of Jane B. Sellers in Death of Gods in Ancient Egypt) is likely related to the way the dazzlingly beautiful constellation of Orion is "held beneath the horizon" by the inexorable motion of precession over the course of millennia.The looming figure of Orion also plays a central role in the gospel account of John the Baptist at the Jordan, in which John declares, "he that cometh after me is mightier than I, whose shoes I am not worthy to bear [. . .] whose fan is in his hand, and he will throughly purge his floor, and gather his wheat into the garner; but he will burn up the chaff with unquenchable fire" (Matthew 3: 11 - 12).In a previous video from 2017 (embedded below) and in this previous post from 2016, I explain that the figure being described in this important text is undoubtedly an Orion-figure, and that the upraised arm of Orion (the arm, in fact, above the "shoulder-star" of Betelgeuse) represents the "winnowing fan" described in the passage from Matthew chapter 3 quoted above. This correlation is extremely significant, because as students of Greek myth know, the figure of a "winnowing fan on the shoulder" is also central to the ancient epic of the Odyssey, as I discuss in my 2016 book Star Myths of the World, Volume Two: Myths of Ancient Greece. This correspondence, as well as other parallels between the Odyssey and the events described in the New Testament gospels, can also be explored further in a previous post entitled, "Parallels between the Odyssey and the Gospels," from 2018.And these are just a few examples of the tremendous importance of the constellation Orion in the system of celestial metaphor underlying the world's ancient myths.For these reasons, I would very much desire to have Betelgeuse continue as a red giant star for hundreds of thousands more years, if not for millions more.Personally, I haven't really noticed that Betelgeuse is any dimmer than usual, but the astronomers who measure such things are telling us that it is very dim, and might be in serious trouble -- so I am sending along thoughts of encouragement to the red supergiant, and urge others to do the same.