Un gros astéroïde frôlera la Terre début 2013

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first_imgUn gros astéroïde “frôlera” la Terre début 2013L’astéroïde 2012-DA14 est dans la ligne de mire de la NASA. Il s’agira du plus gros astéroïde à frôler la Terre, l’an prochain, le 15 février 2013.Se déplaceant à la vitesse de 8 kilomètres par seconde, l’astéroïde 2012-DA14 mesure pas moins de 45 mètres (soit un demi-terrain de football), pèse environ 120 millions de kilos et est en mesure de pulvériser des centaines de kilomètres carrés en cas d’impact. Mais bien qu’il se dirige droit vers la Terre, il ne devrait pas entrer en contact avec elle et se contentera de “frôler” notre planète, d’après les spécialistes. Le passage le plus proche de 2012-DA14 se fera ainsi le 15 février 2013, lorsqu’il se situera à seulement 24.000 kilomètres de la Terre. À lire aussiBoisson, météorite et Facebook, les actus sciences que vous devez connaître ce 5 septembreD’ici là, il continue toutefois d’être surveillé par les scientifiques de la NASA. “C’est le plus grand objet qui est venu si près de la Terre depuis que nous avons lancé […] notre programme de surveillance” a déclaré Lindley Johnson du programme d’observation des objets géocroiseurs de la NASA cité par Canoe.ca. Son collègue Don Yeomans souligne de son côté que l’astéroïde va passer à l’intérieur de l’anneau géostationnaire de la Terre, là où se trouvent les satellites de communication. Il est toutefois très peu probable, selon lui, que l’objet céleste heurte la Terre. Ce qui n’empêche pas les scientifiques de garder un oeil dessus.En effet, “l’orbite de DA14 est très semblable à la Terre” et il repassera dans l’entourage de notre planète en 2020. C’est durant ce deuxième passage que les chances d’impact augmenteront légèrement (une chance sur 77.000 de frapper la Terre). “Ce n’est pas un problème en 2013 et presque pas un problème en 2020, mais vous ne pouvez pas l’exclure”, a déclaré M. Yeomans. Rappelons qu’en 1908, un astéroïde de taille semblable à DA14 a frappé un coin reculé de la Sibérie. Il avait détruit 2.150 kilomètres carrés de forêt et avait répandu une vague de chaleur ressentie à environ 65 kilomètres du point d’impact.Le 16 mars 2012 à 16:41 • Maxime Lambertlast_img

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