|
|
发表于 2016-9-16 22:24:33
|
显示全部楼层
今天真巧，著名的华尔街日报有篇陨石方面的长篇文章。没有翻译，不知道合不合适转上来
Scientists: No, the Rock You Found Is Not a Meteorite
Thousands of space rock fans want to verify their meteorwrongs; ‘I don’t chat’
Randy Korotev, a lunar geochemist in the Department of Earth and Planetary Sciences at Washington University in St. Louis, receives lots of questions about meteorites. Photo: Dave Gheesling
By
Dana Heide
Sept. 15, 2016 10:16 a.m. ET
21 COMMENTS
Randy Korotev, a lunar geochemist, has spent decades studying meteorites.
If you think you found one, don’t call him.
Scientists all over the U.S. are being increasingly hit with queries from people who think they have discovered a meteorite. Some receive boxes filled with rocks every month and spend hours a day looking at pictures of rocks sent to them. To almost all of the meteorite-enthusiasts their response is: No. It’s a meteorwrong, not a meteorite.
A meteorite
Dr. Korotev, a 67-year-old professor in the Department of Earth and Planetary Sciences at Washington University in St. Louis, was contacted 2,719 times by 1,337 different people from at least 68 countries on meteorite-related matters last year, despite the fact that he stopped taking calls four years ago. He has a bluntly worded note on a website that includes a section titled “Rude Admonishments.” It starts: “I’m sorry, but you have not found a meteorite.”
“I have heard many wonderful stories from people who swear that they saw the rock fall, that the rock wasn’t in their driveway yesterday, or that it split their tree in two. I can’t explain how your rock got to be where you found it, but I can say that it is not a meteorite,” he says on the site. He goes on to note that most of the rocks that mysteriously show up were “just the right size for throwing.”
Dr. Korotev said he isn’t trying to be mean, it’s just a matter of time management. “People want to talk about it for hours,” he said. “I don’t chat.”
His voicemail asks people who think they found a meteorite to send him an email. “I can’t identify meteorites over the phone.”
The TV show “Meteorite Men,” with Steve Arnold and Geoff Notkin, boosted interest in looking for rocks from space. Photo: Rob Kim/Everett Collection
There are various theories about what’s causing the current shower of interest. Many cite the TV show “Meteorite Men,” which ran on the Science channel from 2009 to 2012. Some scientists see a spike in queries whenever there is a big meteor shower or media coverage of the fall of a meteorite. The American Meteor Society and the International Meteorite Collectors Association both report seeing an increase in inquiries. (A meteor is the flash of light in the sky; a meteorite is the piece that hits the ground.)
Alan Rubin, adjunct professor at the Department of Earth, Planetary, and Space Sciences at the University of California, Los Angeles, receives five to 10 boxes filled with rocks every month. “Some people send me a box with 60 or 70 different rocks,” Dr. Rubin said. But out of the 2,000 to 3,000 boxes he has received in the last 33 years, he recalls only three to four rocks turned out to be real meteorites.
Jason Utas, a graduate student at UCLA who has gone out on meteorite-scouting expeditions, had to tell one hopeful hunter that what he found was just dry deer droppings. Another time, somebody brought in a chunk of a road because she thought it looked like a piece of a meteorite. “It happens,” said Mr. Utas. “After hours of looking for a meteorite, you think maybe it could be one.”
“The most common meteorwrong that we get is industrial slag,” said Laurence Garvie, curator for the Center for Meteorite Studies at Arizona State University. After Dr. Garvie was on “Meteorite Men,” he and his colleagues received about a half-dozen boxes with rocks every week. “It became quite a burden,” he said.
Arizona State suspended its Meteorite Identification Program in 2010, “due to a substantial rise in demand as well as budget constraints and staff limitations,” the school website says. Now the University encourages people to bring their findings to one of two public events a year when scientists will look at them.
“There are many people who are desperately looking for somebody who can take a look at their rock,” said Dr. Melinda Hutson, curator of the Cascadia Meteorite Laboratory at Portland State University. She gets emails two to five times a day from people who think they found a meteorite.
Portland State posts meteorite-identification tips on its website and advises that it won’t return a sample if it isn’t a meteorite. “We receive far too many ‘meteor-wrongs’ to mail them all back.”
Dr. Korotev was once approached by a man who kept a rock on a shelf for decades. His grandfather had told him he had found it while working in the field and that it was a meteorite. After he died, the grandchild wanted to find out if it really was and sent a picture to Dr. Korotev. It turned out that it wasn’t.
Dr. Korotev with a meteorite in Antarctica in 1998. Photo: Randy Korotev
About 15 years ago, he was contacted on meteorite matters by nonscientists around 50 times a year, he said. He found himself giving the same responses over and over.
Despite his admonishments, inquiries continue. “The peak is always Monday morning,” he said. “Some people argue with me.”
Peter Jenniskens, meteor astronomer at the SETI Institute in Mountain View, Calif., works on making predictions of meteoroid-impact damage on Earth more accurate. When one hit near Sutter’s Mill in California in 2012, Dr. Jenniskens asked the public to assist him by looking for pieces.
That is when Wendy Guglieri, a 69-year-old retiree from Placerville, Calif., started to hunt for meteorites.
“Just imagine that it’s billions of years old and it comes from so far away,” she said. “And this little rock has managed to land on the earth. That blows my mind, and the fact that I can hold it in my hands is absolutely miraculous to me.” After many hours of searching, she hasn’t found a meteorite, but together with four other enthusiasts, keeps on looking.
If people do find a suspected meteorite from a recent fall, Dr. Jenniskens urges them not to pick it up with bare hands. One of the most interesting things about meteorites for scientists is that they transport organic material from outer space to the Earth. Touching it messes up this material. Also, the salt in human sweat may make meteorites rust, because they can contain iron. “We ask people to touch it only with aluminum foil,” he said.
A meteorite Photo: Peter Jenniskens
In a small white plastic box in his office, Dr. Jenniskens keeps examples of the types of rocks people have sent him. There are oval-shaped black ones with even surfaces and weirdly shaped, heavy black rocks. Lying next to them are real meteorites. “The clue is the fusion crust,” he said. “It’s like somebody dips it into chocolate.”
But sometimes even the experts get confused. In Dr. Jenniskens’s white box is one specimen he found himself while searching for a meteorite in a place where an impact happened. The piece is perfectly round and a little rusty.
“You really want it to be something special,” he said. When he had it tested, it turned out to be from an old piece of farming equipment.
|
评分
-
查看全部评分
|
|Archiver|手机版|中陨网✪国陨网
( 冀ICP备10012798号-1 )
发表于 2016-9-16 01:06:35
发表于 2016-9-16 05:10:50
发表于 2016-9-16 20:25:14
