Examination of a meteorite has revealed an unexpected gem , a slice of a comet work at the birth of the Solar System carried safely to Earth encased in part of an asteroid .
Meteorites are divided into different families found on the body they get from . Some are objet d’art of the Moon or other planet criticise off when turgid object struck these earth , while others reveal big differences in the composition of the asteroid from which most meteorite amount . This makes infinite John Rock so cute the great unwashed will go all the way to Antarctica to find them .
The LaPaz 02342 meteorite was collected on the icefield of the same name . Most of it is a fairly typical carbonic chondrite meteorite . Dr Larry Nittlerof the Carnegie Institution searched it for presolar grain , remnant materials from before the Solar System even formed , which such meteorites sometimes contain . Instead , he found something even more precious , a piece of material with the theme of a comet whose meth has boil off .
comet formed much further out from the Sun than asteroids , and therefore arrest ice that would dissolve away in hotter locations . We ’ve also learned from missions to them , and from watch what chance when the ice thawing , that comet have more carbon copy than asteroid . We ’ve had to go into space to taste them because crank is so much less probable to survive entering the Earth ’s atmosphere than rock .
incase inside an asteroid , however , cometic cloth has a much honest opportunity of surviving the rut of introduction , as LaPaz 02342 has proved .
" When Larry and Carles showed me the first negatron images of the carbon - rich cloth , " Arizona State University’sDr Jemma Davidsonsaid in astatement , " I knew we were attend at something very rare . It was one of those exciting import you live for as a scientist . "
InNature AstronomyDavidson and Nittler conclude the 0.1 - millimeter - wide ( 0.004 - in ) anomaly make in the Kuiper Belt past Neptune , becoming a comet ’s building block before light into the inner Solar System as a result of retarding force applied by the surrounding flatulency . The idea materials were transported from the out Solar System in the early stage of its geological formation is favored by astronomer , but severely to prove .
The fragment is deep in Na in addition to the carbon and oxygen concentrations that are its identifying characteristic . It also has more of the pre - solar silicates Nittler was originally seeking than the surrounding asteroid , all of which help build a picture of the other comets .
Antarctica does n’t get any more meteorite than the rest of the major planet , but they are much easier to spot against the relentless livid than when quickly cover up by plant or dust .
