A 1.6 - kilometer - wide ( 1 - mile ) “ potentially risky ” asteroid scheme passed by Earth over the weekend .
1999 KW4is abinary system – two blank space object close enough in proximity to orbit each other – that was first discovered on May 20 , 1999 , by the Lincoln Near - Earth Asteroid Research ( LINEAR ) project in New Mexico . observation over the last two decades have mark the near - Earth object ( NEO ) as “ potentially hazardous ” give its minor chance of colliding with Earth . as luck would have it for us , this time it came within a relatively safe distance of around 5 million kilometre ( 3 million miles ) from Earth . It ’s travelling at some 77,200 km ( 48,000 mi ) per hour , making its closelipped approach at 7:05 pm EST on May 25 , and wo n’t be that close again until 2036 . finally , its route could collide with Earth , but radar measurement indicate no substantial prospect of such an event anytime in the nextmillennium .
The asteroid - pair is unique in its characteristics . The main aim spins like a top with a ridgeline around its equator , according toNASA . Its humble moonlight , roughlyone - thirdthe size of Earth , revolve 2.6 km ( 1.6 land mile ) every 16 hours . Las Cumbres Observatorysaysthe main object ’s shape is “ more or less squashed at the poles and with a mountain ridge around the equator , which run all the way around the asteroid . This ridge gives the primary an appearing like to a walnut or a spinning top . ”
Astronomers know of more than 20,000 NEOs , over 1,800 of which are considered potentially hazardous , but most are small . quad experts do n’t typically study NEOs unless it ’s of import to the safety of Earth . As such , experts originally this year launched the International Asteroid Warning connection ( IAWN ) campaign to test our capability of qualify and prepare for a hazardous asteroid . NASA and several federal bureau , as well as a smattering of external organizations , executed asimulationthat mimicked what would happen if an asteroid was correct to collide with Earth ( pinch : it did not end well for New York City ) .
