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(89959) 2002 NT7 (also written (89959) 2002 NT7) is a near-Earth object (NEO) with a diameter of 1.2 miles[1] (2 kilometers) that became the first object observed by NASA's NEO program to be assigned a positive rating on the Palermo Technical Impact Hazard Scale,
for a potential impact on February 1, 2019. Despite inflammatory press
reports, the object had a "low probability" of impact, approximately one
in a million.[1]
Further observations of the object quickly re-rated the threat lower.
As of July 25, 2002, the hazard rating on the Palermo scale had been
lowered to -0.25. However, the discovery of an object with an initial
Palermo hazard rating of 0.06[2] was a historical event for the NEO observation program.
2002 NT7 was removed from the Sentry Risk Table on August 1, 2002.[3]
It is now known that on January 13, 2019 the asteroid will safely pass 0.4078 AU (61,010,000 km; 37,910,000 mi) from the Earth.[4]
On January 30, 2020 the asteroid will pass 0.02718 AU (4,066,000 km; 2,527,000 mi) from 2 Pallas.[5]
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æ ¹æ®ç°å¨ç轨éè§æµæ°æ®ï¼2019å¹´1æ13æ¥è¿å¢å°ç¹æ¶ï¼è·ç¦»å°ç约0.4078天æåä½ï¼6101ä¸åç±³ï¼ã2020å¹´1æ30æ¥ï¼è¿é¢å°è¡æä¼ä»è·ç¦»æºç¥æï¼2å·å°è¡æï¼0.027天æåä½å¤æ è¿ï¼407ä¸åç±³ï¼ã
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