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Posted: 16-02-2013 02:37 Post subject:

Coincidentally enough I saw a remarkably bright meteor here in the southern US Friday morning at 4:25 GMT. Lasted several seconds and pieces breaking off. Anyone know what time the one in the Urals hit?

Posted: 16-02-2013 08:51 Post subject:

Posted: 16-02-2013 19:02 Post subject:

Looks like 'fireball season' is early this year.

When I'm out with my dog at night, I keep an eye on the sky, because I just love the sight of a meteor. I've seen several good ones that way.

Perhaps we're passing through a rocky patch?

Posted: 16-02-2013 20:28 Post subject:

The fireball reported in the (San Francisco) Bay Area occurred circa 0345 GMT Saturday morning (today).

The one reported from Cienfuegos (central Cuba) is reported to have occurred circa 0100 GMT on Friday (circa 8 p.m. Thursday local time).

Posted: 17-02-2013 02:35 Post subject:

If this had happened in the lead up to the so-called Mayan End-Of-Times nonsense, the Doomsdayers would have whipped themselves up in excitement and trying to convince everyone else that "it's all true, we're all going to die"...

Posted: 17-02-2013 10:49 Post subject:

Russian meteor: lack of fragments sparks conspiracy theories
Thousands of Russian emergency workers sent out to clear up the damage from a meteor seen breaking up over Ural mountains have failed to find fragments of the rock, sparking conspiracy theories about secret weapons and acts of God.
[video of witness]

Divers searched a lake near the city of Chelyabinsk, where a hole several metres wide had opened in the ice, but had so far failed to find any large fragments, officials said. Search teams said they had found small objects up to about 1 cm wide that might be fragments, but no larger pieces.

The scarcity of evidence on the ground has fuelled scores of conspiracy theories over what caused the fireball and the huge shockwave that hit Chelyabinsk, which plays host to many defence industry plants.

Nationalist leader Vladimir Zhirinovsky told reporters in Moscow it could have been "war-mongers" in the United States. "It's not meteors falling. It's a new weapon being tested by the Americans," he said.

A priest from near the explosion site called it an act of God. Social media sites were flooded with speculation about what might have caused the explosion.
"Honestly, I would be more inclined to believe that this was some military thing," said Oksana Trufanova, a local human rights activist.
Asked about the speculation, an official at the local branch of Russia's Emergencies Ministry simply replied: "Rubbish".

Residents of Chelyabinsk, an industrial city 1,500 km (950 miles) east of Moscow, heard an explosion, saw a bright light and then felt a shockwave that blew out windows and damaged the wall and roof of a zinc plant.
The meteor travelled through the atmosphere at 19 miles per second, according to Russian space agency Roscosmos, leaving a long white trail visible as far as 125 miles away.

NASA estimate the object was around 55 feet across before entering Earth's atmosphere and weighed about 10,000 tons.
It exploded miles above Earth, releasing nearly 500 kilotons of energy - about 30 times the size of the nuclear bomb dropped on the Japanese city of Hiroshima in World War Two, NASA added.
"We would expect an event of this magnitude to occur once every 100 years on average," said Paul Chodas of NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California.
"When you have a fireball of this size we would expect a large number of meteorites to reach the surface and in this case there were probably some large ones."

The Chelyabinsk regional governor said the strike caused about 1 billion roubles ($33 million) worth of damage.
Life in the city had largely returned to normal by Saturday although 50 people were still in hospital. Officials said more than 1,200 people were injured, mostly by flying glass.
Repair work had to be done quickly because of the freezing temperatures, which sank close to -20 degrees Celsius (-4 Fahrenheit) at night.

Emergencies Minister Vladimir Puchkov inspected the damage after President Vladimir Putin sent him to the region.
His ministry is under pressure to clean up fast following criticism over the failure to issue warnings in time before fatal flooding in southern Russia last summer and over its handling of forest fires in 2010.

http://www.telegraph.co.uk/science/space/9874790/Russian-meteor-lack-of-fragments-sparks-conspiracy-theories.html

Posted: 17-02-2013 10:54 Post subject:

If you think of it in astronomical terms, the UK was VERY VERY lucky.

Posted: 17-02-2013 11:06 Post subject:

Streaking meteor unleashed biggest blast in a century
BY STEPHEN CLARK
SPACEFLIGHT NOW
Posted: February 15, 2013

Editor's Note: NASA has revised their size and energy estimates for the Russia meteor upon review of further data. Scientists now believe the small asteroid was about 17 meters, or 55 feet, in diameter and had a mass of 10,000 tons. The revised estimate of energy unleashed by the meteor is about 500 kilotons, more than 30 times the blast yield of the atomic bomb dropped on Hiroshima.

A meteoric blast over Russia on Friday was the biggest in more than 100 years, according to scientists, releasing 500 kilotons of energy, shattering windows, and injuring more than 1,000 people.
The injuries were mostly cuts and bruises from broken glass, according to Russian state news reports.
The meteor appeared at 9:20 a.m. local time (0320 GMT; 10:20 p.m. EST) near Chelyabinsk in Russia's Ural Mountains.

NASA scientists told reporters Friday a 55-foot-wide asteroid streaked over Russia at 40,000 mph, briefly glowing as bright as the sun as it broke apart from intense heat and pressure and plowed deeper into the atmosphere.
"This is the largest recorded event since the Tunguska explosion in 1908," said Paul Chodas, research scientist in the Near-Earth Object program office at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

Until Friday, Tunguska was the modern event most often referenced by scientists to illustrate the destructive effects of a meteor. An exploding comet or asteroid in June 1908 leveled 800 square miles of desolate forest near the Podkamennaya Tunguska River in Siberia.
The intensity and damage from Friday's meteor was much lighter, but scientists believe it outranks any known meteor since Tunguska.

Chodas called the Russian meteor a "tiny asteroid" [Phew! Back on thread! Wink

] and said it approached in a north-to-south direction, meaning there is no chance the object was related to the flyby of asteroid 2012 DA14, which harmlessly flew more than 17,000 miles from Earth later Friday.

The meteor over Russia left a twisting trail of vapor hundreds of miles long. A European weather satellite 22,300 miles above Earth spotted the contrail with an imaging camera.

Bill Cooke, head of the meteoroid environments office at NASA's Marshall Space Flight Center in Alabama, said the asteroid entered the atmosphere at an angle of about 20 degrees and disintegrated between 12 and 15 miles above Earth, sending a shock wave to the surface powerful enough to bust windows and set off car alarms.
The energy released by the meteor was equivalent to about 500,000 tons of TNT, more than 30 times more powerful than the atomic bomb dropped on Hiroshima, Cooke said.
Scientists estimated the meteor's energy from observations by infrasound stations designed to monitor compliance with the Comprehensive Nuclear-Test Ban Treaty.

Officials with the Russian Emergencies Ministry told the state-run RIA Novosti news agency about 50 people were hospitalized with injuries, and up to 1,200 people sought medical treatment.
Astronomers say some fragments of the object could have reached the surface, and Russian news outlets report unconfirmed findings of meteorites in the region.

Amateur videos posted to YouTube showed the object plummeting through the atmosphere, followed moments later by the thunderous sound of sonic booms or explosions.

Asteroid 2012 DA14 is much larger than the meteor over Russia. It measures about 150 feet wide and would have struck Earth with energy equivalent to 2.4 million tons of TNT.

Friday's flyby was a near-miss in cosmic terms, and it was the closest buzz by an asteroid of its size in recorded history. Experts say similar-sized asteroids are predicted to reach that distance from Earth every 40 years. An impact with Earth from an asteroid the size of 2012 DA14 is expected about every 1,200 years.
Asteroid 2012 DA14 flew by Earth on a south-to-north course, and its closest point to Earth occurred over Indonesia at 1925 GMT (2:25 p.m. EST).

Astronomers in Spain discovered asteroid 2012 DA14 in February 2012, and its flyby of Earth was known nearly a year ago.
But the spectacular meteor fall over Russia came with no warning.

According to Cooke, an analysis of the meteor's trajectory shows it approached from the day side of Earth.
"It was in the daylight sky, and telescopes can't see objects in the daytime," Cooke said Friday in a conference call with reporters.

The coincidental cosmic encounters could raise awareness about the potential of asteroid and comet impacts on Earth. Scientists are sure they have found the majority of the largest asteroids, which could wipe out civilization on Earth, but experts believe the space catalog covers just 1 percent of the objects the size of asteroid 2012 DA14.

Rep. Lamar Smith, R-Texas, said the House Science Committee will hold a hearing in the coming weeks to examine ways to better identify and address asteroids that pose a potential threat to Earth.

NASA's annual budget for asteroid detection and monitoring is about $20 million, according to Dwayne Brown, an agency spokesperson. Some of the funding is distributed to telescope teams around the world who scan the sky for asteroids.

Public-private partnerships could foster opportunities to find threatening asteroids.
The B612 Foundation, a non-profit organization founded to help protect Earth from asteroids, plans a privately-financed space telescope for launch in 2018. The Sentinel Space Telescope will discover and catalog 90 percent of near-Earth asteroids larger than 350 feet, and about half of near-Earth asteroids larger than 100 feet.
Ed Lu, chairman and CEO of the B612 Foundation, said Friday's asteroid encounters are a "wake-up call that the Earth orbits the sun in a shooting gallery of asteroids, and that these asteroids sometimes hit the Earth."

NASA has a Space Act Agreement with the B612 Foundation to share data, but the space agency has not agreed to provide any funding to the project.

http://spaceflightnow.com/news/n1302/15meteor/

Posted: 17-02-2013 11:28 Post subject:

So....how much is it worth?

Posted: 17-02-2013 12:04 Post subject:

Posted: 17-02-2013 12:27 Post subject:

Posted: 17-02-2013 14:10 Post subject:

A big hitter from the past.

Posted: 17-02-2013 14:52 Post subject:

could they have not found bits because its ice?

Posted: 17-02-2013 19:42 Post subject:

Posted: 17-02-2013 19:52 Post subject:

An article in Astronomy Now is about asteroids in general. Although it was written just before the close encounter with 2012 DA14, it still give useful info:

Taking a closer look at near-Earth asteroids
BY KEITH COOPER
ASTRONOMY NOW
Posted: 14 February 2013

...

..more pertinent this week is a much smaller Apollo, a 40-50 metre wide asteroid designated 2012 DA14, which will make a close fly-by of Earth at a distance of just 28,000 kilometres.

"We will have an observational campaign around the time of its closest approach to get as much information about it as we can, both optically and with radar," says Lindley Johnson, who is the Programme Executive for NASA's NEA observation strategy. "DA14 is coming so close that at its closest approach it is moving too fast for our radars to even keep up with it." Shocked

But can we declare that DA14 absolutely is not going to collide with Earth? Johnson is assured that it is safe - this time around. "Since it was discovered a year ago we have well established the near term orbit and know how close it comes to Earth, so for this pass in February we know the orbit well enough," he says.

However, such close fly-bys inevitably result in Earth's gravity altering the asteroid's orbit, so what will that mean for DA14? "We'll need to track it as it moves away from Earth to determine how much it has been perturbed in order to establish what its future orbit is going to be," Johnson tells Astronomy Now. Now, in most of these cases where there is this closer pass, it perturbs the orbit so much that it is no longer going to be a hazard, but there is a small chance that it could actually put it in an orbit that brings it close to Earth again some time in the future."

Eventually these near-Earth asteroids, if they do not collide with us, will over the course of many millions of years spiral into the Sun or be ejected out of the Solar System by the Sun's gravity. That's not to mean the danger of near Earth asteroids will pass, for new bodies are continuously sent in-system by the gravitational nudges of the planets. For example, the Amor asteroids cross the orbit of Mars but don't quite reach Earth - asteroid (433) Eros, visited by NASA's NEAR-Shoemaker spacecraft around the turn of the millennium, is an Amor. But such asteroids don't remain Amors forever - these are the Atens and Apollos of the future (unless of course, they are captured by the gravity of Mars and become moons of the red planet, as in one hypothesis for the origin of Mars' moons Phobos and Deimos). Then there are the near-Earth comets, 93 of which are known at present.

Our fears of an asteroid colliding with Earth are a little over-hyped, for the biggest and deadliest of such impacts play out over timescales of millions of years. For instance a five kilometre asteroid is expected to collide with Earth on average just once every 20 million years. So it's unlikely civilisation is going to be wiped out by an asteroid any time soon. It's the smaller, more frequent ones we must look out for, which could take out a few city blocks or splash into the sea causing a tsunami that devastates many coastal regions. By studying harmless fly-bys such as that of 2012 DA14, we stand to learn much more about how these smaller near Earth asteroids act when they do come close to our planet, so we can better predict how they will behave in the future and, if the nightmare scenario does come to pass, give us time to figure out how to deflect them.

http://www.astronomynow.com/news/n1302/14asteroids/