It was an ordinary day. Reading a story in an old newspaper titled "Any day now, expect a new star." The sub-head read...Temporarily, thanks to a dim body that flares up in a nova every 80 years." Story was written by Anthony R. Wood who writes for The Philadelphia Inquirer. So....with a name like that....his story must be interesting! (Yeah...I know, my name has an 'S" on the end of it). Anyway...here's the story...
Any night now, the astrophysicists tell us, a new star will appear in the night sky - about as bright as the North Star - the result of a cosmic explosion in a distant constellation millennia ago. NASA scientist Rebekah Hounsell has called it "a-once-in-a-lifetime event that will create a lot of new astronomers out there." Once you see it, however, don't get too attached to it. The so-called recurring nova star, T. Colronae Borealis, which periodically mutates into an earth-size hydrogen bomb, will flame out in less than a week. But, if you're around, you'll get another shot at seeing it at the beginning of the 22nd century. Precisely when the nova, affectionately known as T CrB in the astronomical community, will be visible is unclear, astronomers say, and nailing the timing is a bit more complicated than predicting what time the sun will rise. It could be sometime this month, maybe even this week, or maybe not until winter. But the evidence is unmistakable that it will appear soon. Astronomers know the explosion has occurred because it happens about once every 80 years, and looking into their backward crystal balls, they have observed that T CrB has undergone a signature loss in star power that has preceded previous cataclysms. The nova - not to be confused with a self-destructing supernova - was last observed in February 1946, and before that, in May 1866. A German priest, Abbott Burchard of Upsburg, sighted it in 1217, according to astrophysicist Brady Bradley, an emeritus professor at Louisiana State University. The priest described it as "a faint star that for a time shone with great light." Edward Sion, astrophysicist at Villanova University, said that mentions of the nova also appear in the Middle Ages writings of Chinese and Korean observers. The new star poses no threat to us. It is 3,000 light years from Earth, which explains the lag: Light travels about 5.9 trillion miles annually. By comparison, the light from our star, the sun, beamed from a mere 93 million miles away, gets here in about 6 minutes. The nova is a "white dwarf," the lesser half of a binary system in which two stars are bound together by gravity. Its partner is a "red giant" that leaks hydrogen to its partner, the white dwarf. "It's almost like a perfect storm," said Sion. The white dwarf is an Earth-sized core of a dead star that is unimaginably hot, perhaps exceeding 180,000 degrees Fahrenheit, by NASA's estimate. When enough hydrogen accumulates on the white dwarf, the result is a nuclear explosion that NASA says is 10 times stronger than the annual output of the sun. Said Sion, "Every 80 years, the white dwarf says 'enough accreted mass already!' I'm going to blow up!" The result is that T CrB becomes visible to earthlings, who call such stars nova, Latin for "new." Where in the sky can you find the "new" star? To find the nova, follow the tail that trails the "scooper" of the Big Dipper. That will lead you to Arcturus, one of the brightest stars in the sky. Just to the east of Arcturus is the Northern Crown constellation, of which T CrB is a member. The nova will be just below the apex of the constellation's little arc of stars, visible to the naked eye, Sion said. It was another extraordinary day in the life of an ordinary guy.
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| A Nova |
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