The two asteroids were going in opposite directions, so were not related.
While everyone was expecting and watching Asteroid 2012DA14, which missed Earth by 26,000 km (17,000 miles), another asteroid blasted through the atmosphere in Russia, injuring more than 1,000 people (mostly by shards of glass caused by the sonic boom). One estimate makes it out to be a 10 tonner (seems a bit small), traveling at 30 kilometers a second. Another astronomer, Margaret Campbell-Brown, claims ultrasound stations show it was 15m wide and around 40 tonnes. Nature quotes the same researcher talking about 15m and 7,000 tonnes. You can see we have a good grip on what happened. [UPDATE: Now it's 10,000 tons and 55 feet wide and stone. The largest object to hit in a century. WUWT. What about the ones that fell over the ocean wonders Jo? How would we know?]
It left a “contrail” and a flash that could be seen for 700km (see these videos –why are people filming while they drive?). It only “missed” by 30 – 50 kilometers and nobody knew it was coming. How little we know. One part of it broke off and smashed into a frozen lake, leaving a 6m hole.
The other asteroid (2012DA) was about 60m (150ft) and 140,000 ton or “Tungusta-size”. The 2012DA was headed northwards. The surprise bolide in Russia was travelling south.
So we are watching for the next one?
Have we got these priorities straight? NASA in total gets about $18 billion a year. Though the annual federal allocation for “planetary defense” is only $5.8 million or so (with a proposal to increase it to $20m). But it’s not like there are many objects to watch: “In 2008 NASA’s Near Earth Object Program spotted a total of 11,323 objects of all sizes.” (#&!)
Watts Up posts a quote from the Wall St Journal:
The chance of another Tunguska-size impact somewhere on Earth this century is about 30%. That isn’t the likelihood that you will be killed by an asteroid, but rather the odds that you will read a news headline about an asteroid impact of this size somewhere on Earth. Unfortunately, that headline could be about the destruction of a city, as opposed to an unpopulated region of Siberia. . . .
What are the odds we’ll be hit with man-made deadly weather? Not much according to the evidence, but the US government spends 6785 times as much trying to prevent that:
“Spending to reduce emissions which contribute to climate change was $38 billion” [Energy Budget and Climate Change, 2012, PDF]
See the photos and videos of the Russian explosion. Compare it the observatory view of 2012DA from Gin Gin (1 hour north of Perth, Australia). What a difference a few thousand kilometers makes… To put the astronomical sizes in perspective, 2012DA was about as far away from us as the Earth travels every 14 minutes. (See the WUWT link above).
Simon Goodwin, an astrophysics expert from Britain’s University of Sheffield, said that roughly 1,000 to 10,000 metric tons of material rained down from space towards the earth every day, but most burned up in the atmosphere. [Reuters]
“The Russian meteorite may take second place for size in a century”
RT.com: “Scientists have compared the incident to the century-old Tunguska event, a huge explosion allegedly caused by a fragment of a comet or meteor.
“It looks like it was something like Tunguska – a 60-meter diameter cosmic body, which fell into the Tunguska taiga in 1908,” said Professor Oleg Malkov, Head of the Star Clusters Physics Department at the Russian Science Academy Institute of Astronomy, as cited by Komsomolskaya Pravda daily.
According to estimates, the energy of the Tunguska blast may have been as high as 50 megatons of TNT, equal to a nuclear explosion. Some 80 million trees were leveled over a 2,000-square-kilometer area. The Tunguska blast remains one of the most mysterious events in history, prompting a wide array of hypotheses on its cause, including a black hole passing through Earth and the wreck of an alien spacecraft.
It is believed that if the Tunguska event had happened four hours later, due to the rotation of the Earth it would have completely destroyed the city of Vyborg and significantly damaged St. Petersburg.”
Watch the shockwave hit people in this office (at 25 seconds)
There is a blind spot from the Southern Hemisphere
The “we” in the headline above means the United States (thanks to US taxpayers). Here in Australia, this could be the only space program we could match funding for. Let’s suggest it. Apparently it’s desperately needed. How about some real political vision?
Three NASA-supported observatories with modest telescopes in the southwestern United States and in Hawaii are making more than 95 percent of near-Earth object discoveries. Because of budget limitations, an observatory at Siding Spring, Australia, the only one looking for these objects in the Southern Hemisphere, has reduced its operations to only occasional observations, leaving a blind spot for unknown objects approaching from the southern skies. [ New York Times]
Volunteers found the 2012DA asteroid
2012 DA14 was discovered in February last year by a group of amateur astronomers at La Sagra Observatory in southern Spain. Jaime Nomen, a dental surgeon who dabbled in astronomy, said his group bought a high-powered telescopic camera and software with the help of a $7,695 grant in 2010 from the Planetary Society, a group founded in 1980 by Carl Sagan to promote space exploration.