The cosmos at our fingertips.
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neufer
- Vacationer at Tralfamadore
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- Location: Alexandria, Virginia
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by neufer » Sun Oct 04, 2009 4:02 am
http://www.universetoday.com/2009/10/02/opportunity-finds-another-big-meteorite/ wrote:
<<It's amazing what a rover can find laying by the side of the road.
The Mars Exploration Rover Opportunity has found a rock that apparently is another meteorite.
3-D version of "Shelter Island" meteorite created by Stu Atkinson.
Less than three weeks ago, Opportunity drove away from a larger meteorite called "Block Island" that the rover examined for six weeks. Now, this new meteorite, dubbed "Shelter Island," is another fairly big rock, about 47 centimeters (18.8 inches) long, that fell from the skies. Block Island is about 60 centimeters (2 feet) across and was just 700 meters (about 2,300 feet) away from this latest meteorite find. At first look, the two meteorites look to be of a similar makeup; Opportunity found that Block Island was is made of nickel and iron.>>
http://www.imdb.com/media/rm4213020672/tt0078748
Art Neuendorffer
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northstar
- Ensign
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- AKA: Sputnick
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by northstar » Sun Oct 04, 2009 8:39 pm
As an outdoor's enthusiast I've seen rock like this several times .. does that mean they're all meterorites? Could I become rich selling them? Or is the rock simply volcanic, the cavities created by gas bubbles.
Toning down is such a mundane task
yet we must do so when politely asked
the job is done the day is long
I go forth and sing a brand new song.
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astrolabe
- Science Officer
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by astrolabe » Sun Oct 04, 2009 9:20 pm
Hello northstar,
I agree because I have also seen rocks of similar appearance, especially on the oval surfaces of some running tracks back in high school, or the lava rocks in some gas bar-b-ques but, sad to say, not any composed of nickle or iron.
"Everything matters.....So may the facts be with you"-astrolabe
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neufer
- Vacationer at Tralfamadore
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- Location: Alexandria, Virginia
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by neufer » Mon Oct 05, 2009 3:46 am
astrolabe wrote:I have also seen rocks of similar appearance, especially on the oval surfaces of some running tracks back in high school, or the lava rocks in some gas bar-b-ques but, sad to say, not any composed of nickle or iron.
Nickle, n. (Zoöl.) The European green woodpecker, or yaffle;
-- called also nicker pecker. It is noted for its loud laughlike note.
![Image](http://img.tfd.com/wn/EE/611F0-picus-viridis.jpg)
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http://en.wikipedia.org/wiki/Mars_meteorite wrote:
<<A Mars meteorite is a meteorite that has landed on Earth and originated from Mars. This could have been the result of an impact of a celestial body on Mars, sending material from Mars into space. Of the many thousand meteorites that have been found on Earth, only 34 have been identified as originating from Mars, most of which have been found since 2000. The 34 Mars meteorites are divided into three rare groups of
achondritic (stony) meteorites:
Shergottites (25),
Nakhlites (7), and
Chassignites (2). Consequently, Mars meteorites as a whole are sometimes referred to as the
SNC group. They have isotope ratios that are said to be consistent with each other and inconsistent with the Earth. The names derive from the location of where the first meteorite of their type was discovered.
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___ Shergottites
The first shergottite, the Shergotty meteorite, fell at Sherghati, India in 1865. Shergottites are igneous rocks. Lherzolitic shergottites (one from Antarctica, two from California) are identified by their deuterium/hydrogen ratios. The crystals appear to be 154-187 million years old and they appear, from cosmic ray analysis, to have spent 2.5 to 3.6 million years in space. There are also basaltic shergottites, some of which appear (from the presence of hydrated carbonates and sulfates) to have been exposed to liquid water prior to injection into space.
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___ Nakhlites
There are 7 known nakhlites, the first of which, the Nakhla meteorite, fell in El-Nakhla, Alexandria, Egypt in 1911 and had an estimated weight of 10 kg. The most recent nakhlite was found in Antarctica on December 15, 2003.
Nakhlites are igneous rocks that are rich in augite and were formed from basaltic magma about 1.3 billion years ago. They contain augite and olivine crystals. Their crystallization ages, compared to a crater count chronology of different regions on Mars, suggest the nakhlites formed on the large volcanic construct of either Tharsis, Elysium, or Syrtis Major.
It has been shown that the nakhlites were suffused with liquid water around 620 million years ago and that they were ejected from Mars around 10.75 million years ago by an asteroid impact. They fell to Earth within the last 10,000 years.
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___ Chassignites
The first chassignite, the Chassigny meteorite, fell at Chassigny, Haute-Marne, France in 1815. There has been only one other chassignite recovered, named Northwest Africa (NWA) 2737. NWA 2737 was found in Morocco or Western Sahara in August 2000 by meteorite hunters Bruno Fectay and Carine Bidaut, who gave it the temporary name "Diderot." It was shown by Beck et al. that its "mineralogy, major and trace element chemistry as well as oxygen isotopes revealed an unambiguous Martian origin and strong affinities with Chassigny.">>
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http://en.wikipedia.org/wiki/Custer_Observatory wrote:
<<Custer Observatory is an astronomical observatory owned and operated by Custer Institute. Located in Southold, New York,
facing Peconic Bay and Shelter Island. Long Island's Oldest Public Observatory, Custer Institute was founded in 1927 by Charles Wesley Elmer (co-founder of the Perkin-Elmer Optical Company), along with a group of fellow amateur-astronomers. The name was adopted to honor the hospitality of Mrs. Elmer, the Grand Niece of General George Armstrong Custer.
The Custer Meteorite Collection, which includes a Shergottite from Mars.>>
Art Neuendorffer
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JohnD
- Tea Time, Guv! Cheerio!
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by JohnD » Mon Oct 05, 2009 10:13 pm
Fair enough to name meteorites after islands - you have to use something.
But why 'Block' and 'Shelter'?
Shelter Island off the US east coast IS full of holes:
http://shelterislandedfoundation.org/4.html
Whereas Shlelter Island in San Diego Harbour is not.
And Block Island isn't the shape of a meteorite.
Is there a system?
John
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geckzilla
- Ocular Digitator
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Contact:
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by geckzilla » Fri Oct 09, 2009 1:54 am
Maybe it's more because the meteorites are like islands of curious rock in a sea of otherwise empty sand.
Just call me "geck" because "zilla" is like a last name.