The Sky is Falling?

The manufacturers of news have done it again. Thanks to CNN, Time, news.com.au, and other gullible “news” purveyors, we learn that Betelgeuse, “the second biggest star in the Universe”, is going to explode “before 2012”, or, in more conservative moments, “in 2012”, placing a “second Sun” in Earth’s sky, turning day into night for several weeks. Further, according to these oracular media sources, we should not fear an apocalypse; rather, we will see Earth showered with “essential elements” such as “gold, silver, and uranium”, ostensibly made by a shower of neutrinos, for which we shall all be grateful. A promising mining opportunity!




This is a true blizzard of nonsense. Here are some facts than may relieve your minds:



The mass of Betelgeuse, though uncertain, is probably near 20 times the mass of the Sun. If it is that massive, it will eventually explode (if it is less than 9 times the mass of the Sun it will not explode).



Betelgeuse is not the “second biggest star in the Universe”. It is the second brightest star in the constellation of Orion. If we generously allow that it may be the “second biggest star in the Galaxy”, then it would be something like the ten billionth biggest star in the Universe.



The actual expected remaining lifetime of Betelgeuse is at least a million years, and possibly several million. The probability that Betelgeuse will explode in 2011 (or 2012) is about 0.000001.



If Betelgeuse explodes the first we will know of the event is the arrival of the light given off by the explosion, closely followed by a blast of neutrinos.



The supernova explosion will shine with the brightness of about 100 million Suns. At Betelgeuse’s distance (about 40 million AU), its flash will provide less than 1/100,000,000 of the intensity of Sunlight on Earth for about two weeks. It may be faintly visible in the daytime sky, and surely will be no more spectacular than the full Moon.



If Betelgeuse explodes it will shower Earth with neutrinos, which will have no significant effect on Earth. The neutrinos will not make “useful elements”: they generally pass through Earth as if it weren’t there.



The gases ejected from the explosion of Betelgeuse will form an expanding shell of relativistic gas traveling at about 5% of the speed of light. The first arrival of these gases at Earth will occur about 12,000 years after the initial flash of the explosion.



The gases striking Earth would amount to about 300 grams per square kilometer over a period of several years. Assuming that about half the incoming mass is gases such as hydrogen and helium and half is heavy elements, Earth would collect a dust layer about 0.000000005 cm thick.

If you want to take advantage of the availability of the freshly synthesized uranium, in the dust, the uranium content will be equivalent to a layer 0.0000000000000001 cm thick on average (that’s less than 1/1000th of the diameter of an atom!) Good luck with the mining!



If that doesn’t entertain you, then perhaps this will : these articles reinforce their apocalyptic message by drawing a parallel with the “predictions” of the Mayan Calendar that “Armageddon” will occur in 2012. Really? The end of the world AGAIN? And what precisely is the Mayan word for “Armageddon”?



This nonsense becomes “news” because some reporters are too lazy to check out the facts with knowledgeable sources, and completely ignorant of the use of numbers.



No, Chicken Little, the sky is not falling.