Post by Chicago Astronomer - Astro Joe on Sept 21, 2004 16:48:44 GMT -6
The Chicago Astronomer, The Chicago Tribune and Toutatis - 20 September 2004
Fellow Chicago Astronomers...
With the approach of the "Spud Rock Toutatis passing by next week, The Chicago Tribune contacted us in referrence to what amateur astronomers would be doing in preparations for it's visit. Although it is highly doubtful that Chicago skies will allow direct observations of the asteroid, it is still a facinating event.
I greatly thank Mr. Janega of the Trib for his story and appreciate his interest and knowledge of astronomy.
www.chicagotribune.com/technology/chi-0409210354sep21,1,7562855.story?coll=chi-news-hed
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50-billion-ton `Spud Rock' is ready for its close-up
By James Janega
Tribune staff reporter
Published September 21, 2004
Any time a 3-mile-long chunk of nickel and iron drifts close to Earth, people take notice, even when it's going to miss.
The next asteroid to miss, one discovered in the 1980s called Toutatis, is a doozy: 1.5 miles wide and weighing 50 billion tons if it were sitting on Earth.
It wobbles out of the solar system's hazy realms every four years, giving astronomers either a thrill or a scare depending on their grasp of orbital ballistics, and then totters back into space.
In its wake this year--besides relief--Toutatis also promises to leave behind a good number of animated backyard astronomers, who will get a better look at it than ever before. On Sept. 29, it will pass within 960,000 miles of Earth--four times the distance to the moon. It will be the biggest thing to pass this way, this close, until 2060.
Considering that Toutatis could wipe out a continent and coat the rest of the planet in ash if it landed, watching the asteroid also has taken on the added appeal for backyard enthusiasts of spying on something a bit dangerous. Astronomers like to point out that Toutatis' gyrations are among the most erratic in the solar system.
"It tumbles in space like a wild madman," said Joe Guzman, founder of the online Chicago Astronomer forum, a group of backyard telescope enthusiasts who share local astronomical observations.
Chicago amateurs with 4-inch-wide telescopes now can see Toutatis tumbling into focus, Guzman said. It is moving south from the constellation Capricornus. The best time to see it in Chicago or, better, the collar counties will be this week, around 10 p.m., just above the southern horizon.
After that, it will dip into the Southern Hemisphere. By the time it makes its close approach in the middle of next week, Australians with big binoculars will be able to see it rush past, moving like a satellite as seen from Earth, only slower.
The last large visitor to come this close was Asteroid 2340, later named Hathor, which came within about 750,000 miles in 1976, says the International Astronomical Union's log of minor planets. In 1937, a half-mile-wide asteroid called Hermes passed within 500,000 miles.
(Subsequently lost to science, Hermes later was formally renamed--as Asteroid 69,230--after scientists found it again about two years ago.)
On Toutatis' 1992 pass, when it came within 2.2 million miles, interest in asteroids was so high that the massive Arecibo telescope in Puerto Rico bombarded it with radar signals, mapping a surface and wobbly rotation that look remarkably like a yam heaved by a child still learning to throw.
That unpredictable spin for a long time fed online rumors, quelled only by the steady application of scientific findings.
One rumor was that Toutatis could at any moment deviate from orbit and hit the Earth (it won't). Another was that it was as big as the asteroid that killed the dinosaurs (it's only half that big, but big enough).
Though the rumors have fallen off, the excitement hasn't. Nor have the nicknames that astronomers give it:
"The `Spud Rock,'" said Guzman. "The `Renegade Rock.' Some people call it `Planet X.' But not in mainstream conversation."
Sophisticated instruments brought to bear on Toutatis in 1996 and 2000 have given experts a pretty good handle on it.
It is made of primordial nickel and iron, said Mark Hammergren, an astronomer at the Adler Planetarium. It is probably 4.5 billion years old--the age of the solar system--and probably a piece of something bigger.
Still, Hammergren said, "we don't know a heck of a lot about asteroids in general."
Academically speaking, that's a scary thought.
Take Toutatis, which is believed to have about one-eighth the mass of the dinosaur-killing asteroid. If it hit Illinois, it would make a crater from the lakefront to Aurora, would instantly destroy everything out to about Bloomington, and would blow off the atmosphere from horizon to horizon. Hammergren said chunks of molten rock would fly hundreds of miles into space and rain back down, igniting massive wildfires wherever they landed. Things wouldn't be much better if it landed in the ocean.
In his planetary geology class, University of Wisconsin professor Steven Dutch makes a point of the rapid expansion in mankind's database of rocks that can kill us.
The first four asteroids were discovered between 1801 and 1807 and were hundreds of miles across. There weren't any more discoveries until 1845. After 1847, there wasn't a year without a discovery.
"Astronomers tended to kind of think, `OK, if we bump into one, that's great,'" Dutch said.
The field gained respect and funding in the 1980s, then really took off after Comet Shoemaker--Levy 9 smacked spectacularly into Jupiter in 1994.
"Now we're beginning to realize if one of these things hits the Earth, somebody's going to die ... that tends to inspire people to look."
The number of known asteroids went from 3,000 in 1981 to 10,000 in 1997. As of August, there were 90,671, according to the International Astronomical Union. Toutatis is among those that stand out.
French astronomers found it in 1989 and named it after a friend of the French cartoon character Asterix the Gaul. Because Asterix had a friend named Toutatis and feared nothing but the sky falling on his head, it's a very funny joke in French.
Despite Toutatis' famous wobble, it still has a remarkably regular four-year orbit, both of which make it a popular target for astronomers. But it may not be a spectacular sight.
"It's not going to be more than a white dot," said Astronomy Magazine senior editor Richard Talcott. He says other events may be more fun to watch, such as the Oct. 27 lunar eclipse, Comet Machholz in December and a winter meteor shower.
"Observationally, I would say by far the most interesting aspect of it is that it's going to be moving pretty fast," Talcott said of Toutatis. "Psychologically, I guess I'd say the most interesting thing is that it would be devastating if it hit the Earth."
Copyright © 2004, Chicago Tribune
