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More than two years after an estimated 20-meter class meteor fragmented high over the Russian city of Chelyabinsk, new data reported by NASA researchers this week reveals that — over a four billion year timeframe — the meteor’s orbital parent body itself had likely been geologically-impacted as many as a dozen times. Two 15- to 20-gram samples of the Chelyabinsk meteorite that NASA obtained from Russia over a year ago reveal a broad range of information about the meteor’s mineralogy, bulk composition and age, as noted at the Lunar and Planetary Science Conference in Houston. These same fragments came off the path of the fireball somewhere around the middle of its trajectory through Earth’s atmosphere, Kevin Righter, the lead for meteoritic sample analysis and the Antarctic meteorite curator at NASA’s Johnson Space Center, told Forbes. He says the fragments — pieces from the outer portion of the meteor itself which streaked across the Russian sky on February 15, 2013 — are typical of more stony-type meteorites and made up of some 90 percent silicate; five percent sulfide; and five percent iron-nickel. The original crystallization age of the parent body asteroid, says Righter, might be 4.5 billion years old. But in this case, he says, they found multiple ages using three or four different chronologic detection techniques. Righter says he and colleagues found evidence for about a dozen different parent-body impact events in pieces of the Chelyabinsk meteorite they studied; ranging from 300 million years ago to as recently as 27 million years ago.


The Chelyabinsk meteor was a superbolide caused by a near-Earth asteroid that entered Earth's atmosphere over Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC), with a speed of 19.16 ± 0.15 kilometres per second (60,000[5]–69,000 km/h or 40,000[5]–42,900 mph).[6][7] It quickly became a brilliant superbolide meteor over the southern Ural region. The light from the meteor was brighter than the Sun, up to 100 km away. It was observed over a wide area of the region and in neighbouring republics. Some eyewitnesses also felt intense heat from the fireball. On account of its high velocity and shallow angle of atmospheric entry, the object exploded in an air burst over Chelyabinsk Oblast, at a height of around 29.7 km (18.4 miles, 97,400 feet).[7][8] The explosion generated a bright flash, producing a hot cloud of dust and gas that penetrated to 26.2 km, and many surviving small fragmentary meteorites, as well as a large shock wave. The bulk of the object's energy was absorbed by the atmosphere, with a total kinetic energy before atmospheric impact equivalent to approximately 500 kilotons of TNT (about 1.8 PJ), 20–30 times more energy than was released from the atomic bomb detonated at Hiroshima. The object was undetected before its atmospheric entry, in part because its radiant was close to the Sun. Its explosion created panic among local residents, and about 1,500 people were injured seriously enough to seek medical treatment. All of the injuries were due to indirect effects rather than the meteor itself, mainly from broken glass from windows that were blown in when the shock wave arrived, minutes after the superbolide's flash. Some 7,200 buildings in six cities across the region were damaged by the explosion's shock wave, and authorities scrambled to help repair the structures in sub-zero (°C) temperatures.


截 至 2013年 2月 15日,在車里雅賓斯克大約有 1,491人,包括 311名兒童受傷,需要接受醫療照顧。衛 生 官員說有 112人住院,報導說官員認為有 2人的傷勢嚴重,多數人都是被玻璃碎片所傷。[1]在爆炸之 後,汽 車的防盜警報設施和行動電話網路都被中斷[23]。在車里雅賓斯克市中心的辦公大樓進行了人員疏 散,學校 也停止上課,主要的原因是因為窗戶玻璃的碎裂[13]。在 9:22,一所學校和幼稚園的窗戶破裂,造 成至少 20 名孩童受傷[24]。 接下來的事件,車里雅賓斯克省的政府官員要求父母將孩童從學校接回家中 [25]。內政部發言人說:一所製 鋅廠大約 600 m2(6,500 sq ft)的原料倉庫和屋頂在此一事件中倒塌 [26]。在車里雅賓斯克,因為當地的溫 度僅有−15 °C(5 °F),窗戶被打破的居民都爭先恐後的以任何可 用的東西遮蓋破口[17][27][28]。 車里雅賓斯克的州長米哈伊爾·尤列維奇表示,當局的主要目標是維護這座 城市的中央加熱系統[13]。他估計 這次事件的損失不會低於 10億盧布(大約 3,300萬美元)[29]。車里雅 賓斯克當局說,公寓家園破碎的窗戶 (不包括陽台的玻璃)將由政府出資代為修護[30]。 在這次爆炸中受損 的建築物之一是大陸冰球聯盟的Traktor Chelyabinsk主競賽場Traktor Sport Palace,競 賽場地將先關閉 進行檢查,安排在這個場地的活動,包括大陸冰球聯盟的季後賽,都將受到影響[31]。 車里雅賓斯克流星雨 被認為是自 1908年通古斯事件以來最大的隕石襲擊地球事件,並且是此類事件中唯一 造成大量傷害的[32] [33]。


وسطی روس میں شہاب ثاقب کے ٹکڑےگرنے کے نتیجے میں زخمیوں کی تعداد گیارہ سو سے تجاوز کر گيیہے۔جدید دورمیںاس طرح کے کسی ایکواقعے میں زخمی ہونے والے افراد کی یہ تعداد غیر معمولی قرار دی جا رہی ہے۔حکامنے متاثرہعلقوںمیں صفايی اور امداد کے لیے خصوصی ٹیمیں روانہ کردیںہیں۔ ب ثاقب چون ہزار کلومیٹر کی رفتارسےزمینکی جانب ایا۔ زمین کی سطح سے کويی پچاسکلومیٹرکی ب یاد رہے دس ٹنوزنیشہا بلندی پر، باس کے ٹٹکڑے ہونےلگے۔دیو ہیکل شہاب کی رفتار کا اندازہ اس بات سے لگایا جا سکتا تھا کہ یہ دبيی سے جدہکاسترہ سو کلومیٹر فاصلہصرفایک سیکنڈ میں طے کر سکتا تھا جبکہ جدید مسافر طیارے یہ فاصلہ دو گھنٹوں میں طےکرتےہیں۔ روس میں شہابیوںکیبارش ایسے موقعے پر ہويی ہے جبزمین کے جنوبی کرے سے ایک سیارچہ گزرنے وال ہے۔ سیارچےکوٹونٹی ب ثاقب،شمالیکرہ سےایا،باس ب ٹویلو ڈیاے فورٹین کا نام دیاگیا ہے۔ ساينسدانوں کا کہنا ہے کہ روس میں تباہی پھیلنےوالشہا لیے،باندونوں واقعات کا کويیتعلقنہیں۔ شہاب ثاقب کے چمکتے ہويے ٹکڑےزمیں پر برسے تو وسطی روس کے چیلیابنسک کےعلقوںمیں لوگ خوف و ہراس میںمبتلہو رل کے پہاڑی سلسلے میں شہاب ثاقب کےٹکڑوں کی بارشدیدنیتھی۔ ر گيے۔ مقامیوقتکے مطابق صبح نو بجکر بیس منٹپراو وسیع پیمانے پر پھیلنے والی اس تباہی کے نتیجے میں کسی کا ہلک نہ ہونابھیایک معجزہ قراردیاجارہاہے۔


15 февраля 2013 года в раионе Челябинска упало довольно заурядное космическое тело. Уникальным это падение сделало место и время. Это первыи в истории случаи падения крупного метеорита в густонаселеннои местности, поэтому никогда еще падение метеорита не наносило такого серьезного ущерба. МОСКВА, 14 фев — РИА Новости. Год назад, 15 февраля 2013 года, жители южного Урала стали свидетелями космическои катастрофы — падения астероида, которое стало первым в истории подобным событием, нанесшим людям серьезныи ущерб. В первые моменты жители региона говорили о взрыве "непонятного объекта" и странных всполохах. Ученые целыи год исследовали это событие, что им удалось выяснить на этот момент — читаите в обзоре РИА Новости.


2 月 15日の朝(現地時間)、ロシアとカサフスタンの国境付近のウラル地方て目撃された落下物による 被害として、衝撃波て割れたカラスなとて 1200人以上の負傷か報告されている。 被害か集中したチェ リャヒンスクにあるチェハルクリ湖ては隕石とみられる破片か回収され、分析か行わ れた。ウラル連邦大 学のViktor Grohovskyさんによると、隕石の中てもっともありふれた「普通コン トライト」と呼はれる 石質隕石て、組成の 10%か鉄ててきているという。 NASAの推算ては、この隕石のもととなった小天体 は重さ 1万 t、幅 17m。秒速 18km、20度以下の 浅い角度て地球の大気圏に飛ひこみ、上空 15~25km前 後てはらはらに壊れたという。約 16時間後に 地球に最接近した数十mサイスの小惑星 2012 DA14とは 軌道かまったく異なるため、両天体は無関係 と判断されている。 小惑星の検出や軌道追跡による衝突確 率の計算といった小天体の監視は世界中て行われている。たとえは 推定サイスか 45mの小惑星 2012 DA14は事前に発見され、軌道の計算から地球衝突のおそれはない ことかわかっていた。たか、その 3分 の 1ほとの大きさとみられる今回の天体の場合は検出か難しく、さ らに地球の昼側からの大気圏突入たっ たために見つかりにくかったという(NASA流星状況局のBill Cookeさんによる)。2008年には数m サイスの小惑星か大気圏突入の数時間前に発見されている。 隕石か家の屋根や自動車に直撃する事故は世 界各地て時々起こっているか(下記〈関連ニュース〉参照)、 現状ては隕石落下による被害を現実的な可 能性としてとらえるのは難しい。


More than two years after an estimated 20-meter class meteor fragmented high over the Russian city of Chelyabinsk, new data reported by NASA researchers this week reveals that — over a four billion year timeframe — the meteor’s orbital parent body itself had likely been geologically-impacted as many as a dozen times. Two 15- to 20-gram samples of the Chelyabinsk meteorite that NASA obtained from Russia over a year ago reveal a broad range of information about the meteor’s mineralogy, bulk composition and age, as noted at the Lunar and Planetary Science Conference in Houston. These same fragments came off the path of the fireball somewhere around the middle of its trajectory through Earth’s atmosphere, Kevin Righter, the lead for meteoritic sample analysis and the Antarctic meteorite curator at NASA’s Johnson Space Center, told Forbes. He says the fragments — pieces from the outer portion of the meteor itself which streaked across the Russian sky on February 15, 2013 — are typical of more stony-type meteorites and made up of some 90 percent silicate; five percent sulfide; and five percent iron-nickel. The original crystallization age of the parent body asteroid, says Righter, might be 4.5 billion years old. But in this case, he says, they found multiple ages using three or four different chronologic detection techniques. Righter says he and colleagues found evidence for about a dozen different parent-body impact events in pieces of the Chelyabinsk meteorite they studied; ranging from 300 million years ago to as recently as 27 million years ago.


Gracas, em particular, as gravacoes de video, Chelyabinsk e um dos 18 meteoritos com os quais foi possivel fazer um calculo retroativo de sua trajetoria, para detectar de qual parte do cinturao de asteroides proveio", indicou Grokhovsky ao jornal "Rossiiskaya Gazeta". Sua idade foi estimada em 4,5 bilhoes de anos, a mesma do Sistema Solar. Apos escutar estes preciosos testemunhos, os cientistas estimam que o asteroide pode ter medido ate 20 metros e pesado 13.000 toneladas. Ao entrar na atmosfera, ele se tornou um objeto dotado de energia equivalente a um milhao de toneladas de TNT, isto e, 30 vezes a potencia da bomba atomica de Hiroshima. "O asteroide se desintegrou em pedacos pequenos a 45 ou 30 quilometros de altitude, evitando causar maiores danos na superficie terrestre", informou, em novembro passado, um grupo de cientistas tchecos. A trajetoria, acrescentam, sugere que o meteorito foi alguma vez parte de um asteroide de dois quilometros de diametro chamado 86039, inicialmente avistado em 1999 e que voltava a passar regularmente perto da Terra. Os cacadores de meteoritos se lancaram na busca de fragmentos, inclusive um precioso e volumoso pedaco de meia tonelada, recuperada no fundo de um lago congelado perto de Chelyabinsk.


Συμφωνα με προηγουμενες εκτιμησεις, οι οποιες βασιζονταν σε τηλεσκοπικες παρατηρησεις των γνωστων αστεροειδων, οι διαστημικοι βραχοι στο μεγεθος του μετεωρου του Τσελιαμπινσκ στη Ρωσια, ο οποιος εκτιμαται οτι ειχε διαμετρο σχεδον 20 μετρα, εισερχονται στη γηινη ατμοσφαιρα μια φορα στα 150 χρονια. Συμφωνα ομως με την πρωτη απο τις μελετες που δημοσιευονται στο Nature, προσκρουσεις που μπορουν δυνητικα να προκαλεσουν καταστροφες ειναι πιθανο να συμβαινουν πολυ συχνοτερα, περιπου μια φορα στα 30 χρονια. Η διαφορα ειναι οτι μεχρι σημερα οι επιστημονες επικεντρωνονταν στους αστεροειδεις διαμετρου ανω των 100 μετρων, οι οποιοι θα προκαλουσαν καταστροφες σε επιπεδο πλανητη η ηπειρου. Η νεα μελετη, αντιθετα, αναγνωριζει οτι υπαρχει κινδυνος ακομα και απο διαστημικους βραχους που εχουν διαμετρο λιγα μετρα, οπως συνεβη στο Τσελιαμπινσκ. Επιπλεον, η ερευνητικη ομαδα υποστηριζει οτι οι προσκρουσεις αυτου του μεγεθους ειναι συχνοτερες απο ο,τι ειχε εκτιμηθει. Η ομαδα ανελυσε δεδομενα απο το παγκοσμιο δικτυο σταθμων του Οργανισμου για τη Συνθηκη Πληρους Απαγορευσης των Πυρηνικων Δοκιμων, οι οποιοι ειναι σχεδιασμενοι να καταγραφουν πυρηνικες εκρηξεις, μπορουν ομως να ανιχνευουν οποιαδηποτε μεγαλη εκρηξη στην ατμοσφαιρα. Η ερευνητικη ομαδα ανελυσε δεδομενα απο το παγκοσμιο δικτυο σταθμων του Οργανισμου για τη Συνθηκη Πληρους Απαγορευσης των Πυρηνικων Δοκιμων, οι οποιοι ειναι σχεδιασμενοι να καταγραφουν πυρηνικες εκρηξεις, μπορουν ομως να ανιχνευουν οποιαδηποτε μεγαλη εκρηξη στην ατμοσφαιρα. Η αναλυση εδειξε οτι τα τελευταια 20 χρονια εχουν εισελθει στην ατμοσφαιρα περιπου 60 αστεροειδεις με διαμετρο μεχρι 20 μετρα. Οι περισσοτεροι ομως δεν εγιναν αντιληπτοι επειδη επεσαν στον ωκεανο η σε απομακρυσμενες περιοχες, αντιθετα με ο,τι συνεβη στο Τσελιαμπινσκ.


More than two years after an estimated 20-meter class meteor fragmented high over the Russian city of Chelyabinsk, new data reported by NASA researchers this week reveals that over a four billion year timeframe the meteors orbital parent body itself had likely been geologically-impacted as many as a dozen times.

The bulk of the object's energy was absorbed by the atmosphere, with a total kinetic energy before atmospheric impact equivalent to approximately 500 kilotons of TNT (about 1.8 PJ), 2030 times more energy than was released from the atomic bomb detonated at Hiroshima.

The Chelyabinsk meteor was a superbolide caused by a near-Earth asteroid that entered Earth's atmosphere over Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC), with a speed of 19.16 0.15 kilometres per second (60,000[5]69,000 km/h or 40,000[5]42,900 mph).[6][7] It quickly became a brilliant superbolide meteor over the southern Ural region.

The number of injured as a result of tkrygrny of meteoroids in central Russia, the number of injured at more than eleven hundred durmynas gyyhy.jdyd aykuaqay like being a rare and special to help out hy.hkamny mtasrhalqunmyn krdynhyn teams left.

These same fragments came off the path of the fireball somewhere around the middle of its trajectory through Earths atmosphere, Kevin Righter, the lead for meteoritic sample analysis and the Antarctic meteorite curator at NASAs Johnson Space Center, told Forbes.

He says the fragments pieces from the outer portion of the meteor itself which streaked across the Russian sky on February 15, 2013 are typical of more stony-type meteorites and made up of some 90 percent silicate; five percent sulfide; and five percent iron-nickel.

On account of its high velocity and shallow angle of atmospheric entry, the object exploded in an air burst over Chelyabinsk Oblast, at a height of around 29.7 km (18.4 miles, 97,400 feet).[7][8] The explosion generated a bright flash, producing a hot cloud of dust and gas that penetrated to 26.2 km, and many surviving small fragmentary meteorites, as well as a large shock wave.

The original crystallization age of the parent body asteroid, says Righter, might be 4.5 billion years old.

But in this case, he says, they found multiple ages using three or four different chronologic detection techniques.

Righter says he and colleagues found evidence for about a dozen different parent-body impact events in pieces of the Chelyabinsk meteorite they studied; ranging from 300 million years ago to as recently as 27 million years ago.