Think of the earth as a billiard ball waiting to be cued up by some passing comet. It's a stock movie plot.
For instance, in the 1984 blockbuster, "Night of the Comet," the Earth passed through the tail of Halley's Comet. (Spoiler Alert!) Everyone turns into red dust except for several rampaging packs of zombie-cannibals and a pair of titillating Valley Girls for the zombies to chase for the next 95 minutes.
President Obama's scientific advisers have had him watch the 1998 thriller, "Deep Impact" over and over. In that movie, you'll remember, U.S. President Morgan Freeman had to face the seven-mile-wide "Wolf-Biederman" comet that promised to make scrapple out of the human race. President Freeman, along with the world's best brains, cobbled together a rocket and a nuclear missile and put the hope and fate of all humanity on Robert Duvall and Tea Leoni (He's 82, she's 47). It's a cautionary tale about the dangers of love; in the thrall of their romantic engagement, they forgot to disengage long enough to shoot the nuclear missile at the comet.
Real comets can be weird enough. In November 1996, a photo taken by an amateur astronomer showed a smudge behind the comet Hale-Bopp. Proof, he concluded, that there was an object the size of Saturn following the comet. He sent it to radio showman Art Bell who declared it was authentic and concluded that there was a huge alien starship following the comet.
This was the news that the Heaven's Gate cult was waiting for. They were a San Diego group of 40 or so who combined the Christian concept of the apocalypse with the science-fiction concept of time travel to different dimensions and worlds. They believed God was fed up and about to dump the earth into His recycle bin and the only hope for human survival was for them to leap to the spaceship that was following Hale-Bopp. Trouble was, they couldn't take their bodies with them. They knew that the trip across space wouldn't be free, so each of them loaded their front pocket with $5.75 to pay for their fare. The fact that 39 of them were found dead of a deliberate barbiturate overdose with a five-dollar bill and three quarters still intact in their pocket didn't bode well for their safe passage. What kind of taxi driver doesn't collect?
Later the University of Hawaii discovered that the photo of the spaceship was one of theirs that someone had altered. The website for the Heaven's Gate cult is still up and can be found at www.heavensgate.com. No, seriously, they could be up there laughing at us.
The Comet of the Last Century was called Kohoutek. It is a long-period comet dropping by about every 150,000 years or so. It was first detected in March of 1973 and promised to brighten the night sky when it passed later in December. Scientists thought it was a gas cloud and theorized it would bring a spectacular display. Instead it turned out to be a big rock and passed the earth barely detectable by the naked eye.
So just 40 years later, we have a new Comet of the Century. Welcome Comet Ison. It is entering our solar system now and will come very close to Mars and also blisteringly close to the sun in November of this year before passing about 40 million miles off the left hand side of earth. Scientists are pretty sure this one is just a frozen ball of gas which should make for an outstanding nighttime display. The comet Ison will be making its closest passage to us on Dec. 25, the birthday of ...
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