Klimmer
Mountain climber
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Aug 14, 2013 - 04:07pm PT
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Russian meteor may have gangmates in tow
Orbital estimates pinpoint 20 asteroids on similar
paths to rock that exploded near Chelyabinsk.
By Maggie McKee
Nature
02 August 2013
http://www.nature.com/news/russian-meteor-may-have-gangmates-in-tow-1.13498
They decided to tackle the problem with brute computational force, running simulations of billions of possible orbits to find the ones most likely to have led to a collision. They then used the average of the ten best orbits to search a NASA asteroid catalogue for known objects on similar paths. They found about 20, ranging in size from 5 to 200 metres across, they report in an article to be published in Monthly Notices of the Royal Astronomical Society: Letters1.
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The best sibling candidate, for instance, is a 200-metre-wide asteroid known as 2011 EO40, whose orbit was calculated from observations taken over just 34 days. That is too short a time to be able to pinpoint its position in the future, says Jon Giorgini, a senior analyst in the Solar System Dynamics Group at NASA's Jet Propulsion Laboratory in Pasadena, California. For that, researchers would need observations taken over the asteroid's two-year orbit, he says.
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The only way to prove a connection would be to collect samples from one of the proposed family members and compare them with meteorites collected from the Chelyabinsk region, says Carlos de la Fuente Marcos. However, a cheaper way to find out whether the suspected siblings have at least a passing resemblance could be to measure their composition from their light spectra.
Chelyabinsk meteoroid -----> meteor -----> meteorite, was estimated to be 18.0m in diameter as it entered into Earth's atmosphere before fragmenting above Russia.
This could be a possible uh, oh ...
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