In a rarity, a meteor hit and an asteroid near-miss on same day
By Irene Klotz
February 15, 2013
BOSTON (Reuters) - An asteroid half the size of a football field passed closer to Earth than any other known object of its size on Friday, the same day an unrelated and much smaller space rock blazed over central Russia, creating shock waves that shattered windows and injured 1,200 people.Follow over the jump for more about the impact itself.
Asteroid 2012 DA14, discovered just last year, passed about 17,200 miles from Earth at 2:25 p.m. EST (1925 GMT), closer than the networks of television and weather satellites that ring the planet.
"It's like a shooting gallery here. We have two rare events of near-Earth objects approaching the Earth on the same day," NASA scientist Paul Chodas said during a webcast showing live images of the asteroid from a telescope in Australia.
Scientists said the two events, both rare, are not related -the body that exploded over Chelyabinsk, Russia, at 10:20 p.m. EST Thursday (0320 GMT Friday) came from a different direction and different speed than DA14.
First, in the guise of a picture being worth 1000 words, here is the PBS's video segment about the blast: Meteor Explosion of Atomic Strength Injures 1,000 in Russia
Paul Davies of Independent Television News reports that 10-ton meteor that fell over Russia with atomic bomb power. The meteor caused a fireball, blowing out windows and injuring 1,000 people.Now for some analysis from Scientific American and Nature: Russian Meteor Largest in Century.
The explosion rivaled a nuclear blast, but the space rock was still too small for existing advance-warning networks to spot
By Geoff Brumfiel and Nature magazine
A meteor that exploded over Russia this morning was the largest recorded object to strike the Earth in more than a century, scientists say. Infrasound data collected by a network designed to watch for nuclear weapons testing suggests that today's blast released hundreds of kilotons of energy. That would make it far more powerful than the nuclear weapon tested by North Korea just days ago and the largest rock crashing on the planet since a meteor broke up over Siberia's Tunguska river in 1908.Scientific American's own reporting appears in What Do We Know about the Russian Meteor? Troubadour on Daily Kos summarized all of the above reporting in Scientific American Gives Details on the Russian Meteor, while Joieau had more of a gallows humor take in God's Gnarly Game of Billiards.
"It was a very, very powerful event," says Margaret Campbell-Brown, an astronomer at the University of Western Ontario in London, Canada, who has studied data from two infrasound stations near the impact site. Her calculations show that the meteoroid was approximately 15 meters across when it entered the atmosphere, and put its mass at around 40 tons. "That would make it the biggest object recorded to hit the Earth since Tunguska," she says.
The meteor appeared at around 09:25 a.m. local time over the region of Chelyabinsk, near the southern Ural Mountains. The fireball blinded drivers and a subsequent explosion blew out windows and damaged hundreds of buildings. So far, more than 700 people are reported to have been injured, mainly from broken glass, according to a statement from the Russian Emergency Ministry.
As for the power of the explosion, estimates now range up to 500,000 tons of TNT. That's 500 kilotons, which is on the high side for a warhead of a Minuteman missile. The implications of that are not lost on Neil DeGrasse Tyson, who also appeared on PBS.Asteroid Careens by as Meteor Delivers 'Buzz Cut' to Earth
On the same day as a meteor hit Russia, an asteroid careened towards Earth. Jeffrey Brown talks to astrophysicist Neil deGrasse Tyson about this cosmic coincidence, how the meteor and asteroid came so close to Earth, what risks it poses and why this is a 'wake-up call.'This blog is still about how to avoid the collapse of the current civilization and takes a science-fiction slant on the topic. An asteroid impact is the perfect merger of the two. On that note, I leave you this graphic I took from Nebris.
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