in good order now , there are about15,000 clump of rockorbiting worryingly close to Earth . These appropriately name Near - Earth Asteroids ( NEAs ) , all within about 0.2 billion klick ( 0.12 billion miles ) from the Sun , champion by our world at irregular intervals , but this month it appear that at least three , possibly four , will all zip by the dingy marble on Wednesday , December 21 .
As report byNEOShield , an external consortium to accost impact threats to Earth , asteroids 2006LH , 2010XN , and 2006XD2 are all decease to pass by Earth .
The first is the smallest being just 45 beat ( 148 animal foot ) in diameter and move at a speed of 9.4 kilometers ( 5.8 miles ) per second . The third , at 260 meters ( 853 substructure ) in length , is by far the most monumental . Moving at 13.6 kilometers ( 8.5 miles ) per secondly , it ’s also the dissipated .
lease ’s just assume that 2006XD2 is astony asteroid , with a mineral composition some that of basalt . Let ’s also assume it ’s globular . Both of these are massive simplification , but it means that we can count on how much energising Department of Energy 2006XD2 will be released if it attain a continent on Earth at a 90 ° angle .
This imply that 2006XD2 has a volume of around 30 billion kilogram ( 33 million tons ) , and would impact the planet with 2.8 quintillion joule of energy . Yes , that ’s a muckle . It ’s still over 100,000 times less up-and-coming than thedinosaur - killing asteroid impact66 million years ago , so no biggie really .
Do n’t worry though ! Although many medium issue would claim that they are going to be “ near - misses ” – and they would be proper in terms of astronomical aloofness – the distances they are going to be at their closemouthed glide slope are n’t worth set out anxious over .
The small 2006LH will be the nigh at 14.5 times the Earth - Moon distance , and the full-grown baddie 2006XD2 will be clear by at 18.9 times the Earth - Moon distance .
Others are reporting that afourth NEA , 2015YQ1 , will also pass by Earth on the December 21 , but we can not control this at present , and NEOShield make no mention of it .
Still , it ’s not a stranger to close encounters with the third rock from the Sun . This sentence last yr , the 7 - cadence - long ( 23 foot ) 2015YQ1 made it within roughly 1.4 times the Earth - Moon space .
If you ’ve got a brawny enough telescope , you might be able to see some of these NEAs depend on their angle of approach relative to the Sun . Regardless , it ’s comforting to be reminded that programs out there exist that keep an eye on all these rocky hoagy , one of which could one daythreaten all life-time on Earth .
