Communiqué du Laboratoire d`Astrophysique de Marseille OAMP/LAM

Contacts
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Philippe!Lamy!!
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Thierry!Botti!
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Communiqué!du!Laboratoire!d’Astrophysique!de!Marseille!
OAMP/LAM!–!CNRS!–!Université!de!Provence!
!
L’Astéroïde!21!Lutétia!:!un!planétésimal!vestige!du!Système!solaire!initial!
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!
Le!10!juillet!2010,!la!sonde!Rosetta!de!l'agence!spatiale!européenne!(ESA)!a!survolé!l'astéroïde!
21!Lutetia.!Lors!du!survol,!les!images!spectaculaires!obtenues!par!le!système!de!caméras!OSIRIS!
de!Rosetta!ont!permis!de!révéler!la! richesse!des!processus!géologiques!de!cet!astéroïde!et!de!
déterminer!sa!densité,!3,4±0,3!g/cm3,!une!des!plus!fortes!mesurées!à!ce!jour!pour!un!astéroïde.!
Ces!observations!laissent!supposer!que!l'astéroïde!21!Lutétia!est!probablement!un!planétésimal!
primordial,!vestige!du!Système!solaire!initial,!qui!ne!s'est!pas!fragmenté!depuis!sa!formation!il!y!
a! environ! 4!milliards! d'années,! contrairement! à! la! très! grande! majorité! (>95%)! des! autres!
astéroïdes.! Parmi! les! membres! de! l’équipe! scientifique,! trois! chercheurs! du! Laboratoire!
d’Astrophysique! de! Marseille!(LAM! –! CNRS/Université! de! Provence)!sont! particulièrement!
impliqués!dans!ce!résultat!exceptionnel,!publié!dans!la!revue!Science.!
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Plus!d’informations!
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Les!laboratoires!français!impliqués!dans!cette!étude!sont!:!!
Laboratoire!d’Astrophysique!de!Marseille!\+,-.!m!nJ#L%$5#'Q!)%!M$2L%J&%]!<!MF!0/G7N!KF!g$2(55#JN!
0F![2$)/N!MF!o%$J/ee/!
LESIA,!Observatoire!de!Paris!\+,-.UnJ#L%$5#'Q!M#%$$%!%'!9/$#%!+($#%!U!nJ#L%$5#'Q!M/$#5!"#)%$2']!<!9F!
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