20,000 Pound Meteor Explodes over Russia, Injuring Hundreds

Friday, February 15, 2013 by Common Dreams
- Common Dreams staff

The dramatic footage captured by a dashboard video camera in the Chelyabinsk region of Russia in the nation's south-central shows what scientists say was a more than 10 ton meteor entering the atmosphere at over 33,000 miles per hour.

Once meteors break through the atmosphere and explode, the pieces that actually hit the Earth's surface are called meteorites. It is so far unclear how much damage on the ground -- and over how large an area -- was caused by actually pieces of the exploded object or by the sonic boom that accompanied the initial explosion. Expert observers calculate that the meteor "pancaked" and incinerated approximately 25 miles above the ground.

The Associated Press reports:

The fall caused explosions that broke glass over a wide area. The Emergency Ministry says more than 500 people sought treatment after the blasts and that 34 of them were hospitalized.

"There was panic. People had no idea what was happening. Everyone was going around to people's houses to check if they were OK," said Sergey Hametov, a resident of Chelyabinsk, about 1500 kilometers (930 miles) east of Moscow, the biggest city in the affected region.

"We saw a big burst of light then went outside to see what it was and we heard a really loud thundering sound," he told The Associated Press by telephone.

Captured from another angle:

Massive Fireball Streaks Across Midwestern Sky

Massive fireball reported across Midwestern sky
By the CNN Wire Staff
April 15, 2010




(CNN) -- Authorities in several Midwestern states were flooded Wednesday night with reports of a gigantic fireball lighting up the sky, the National Weather Service said.

The fireball was visible for about 15 minutes beginning about 10 p.m., said the National Weather Service in Sullivan, Wisconsin, just west of Milwaukee.

"The fireball was seen over the northern sky, moving from west to east," said the NWS in the Quad Cities area, which includes parts of Iowa and Illinois.

"Well before it reached the horizon, it broke up into smaller pieces and was lost from sight," the service said. "Several reports of a prolonged sonic boom were received from areas north of Highway 20, along with shaking of homes, trees and various other objects including wind chimes," it said.

It said the fireball was seen across parts of Missouri, Illinois, Indiana and Wisconsin. CNN affiliate WISN-TV said that people in Ohio also saw it.

Video from WISN showed a massive ball of light exploding across the sky. The Doppler Radar from the Quad Cities weather service appeared to capture a portion of the smoke trail from the fireball at just after 10 p.m., the NWS said. It appears as a thin line extending across portions of Grant and Iowa Counties in Wisconsin.

There has been no official determination as to what caused the fireball, the NWS in Sullivan said.

However, it said there is a meteor shower called Gamma Virginids that occurs from April 4 to April 21, with peak activity expected on Wednesday and Thursday.

"A large meteorite could have caused the brilliant fireball that has been reported," the National Weather Service said.

The NWS in Quad Cities said that it was unknown if any part of a meteorite hit the ground.
According to NASA, a meteor appears when a meteoroid -- a particle, chunk of metal or stony matter -- enters the Earth's atmosphere from outer space.

"Air friction heats the meteoroid so that it glows and creates a shining trail of gases and melted meteoroid particles," it said. "People sometimes call the brightest meteors fireballs."

Near-Earth Object 2010 AL30

Near-Earth Object 2010 AL30



Photographer: Patrick Wiggins; Patrick's Web Site
Summary Author: Kurt Fisher; Patrick Wiggins
March 2010 Earth Science Picture of the Day Viewer's Choice

Most North Americans slept through the morning of January 13, 2010 as near-Earth object (NEO) 2010 AL30 silently moved across the night sky. Its path brought it to an altitude of about 122,000 km, which is one third of the distance to the Moon. 2010 AL30 is an asteroid approximately 10 to 15 m across. As shown above, Patrick Wiggins followed its passage using a 35 cm telescope and CCD camera. 2010 AL30 is estimated to be part of a NEO population of several thousand similar objects. On average, one 10-15 m diameter asteroid passes within one lunar distance of the Earth about once a week. If 2010 AL30 had entered the Earth's atmosphere, it would have created an air burst equivalent to between 50 kT and 100 kT (kilotons of TNT). The Nagasaki "Fat Man" atom bomb had a yield between 13-18kT.

On January 22, 2010, the National Research Council of the National Academy of the Sciences released its final report as requested by the United States Congress. This report recommended an optimal approach to complete the census of NEOs larger than about 140 m as well as an optimal approach for deflecting a NEO that threatens impact with the Earth. The report recommended that the census of NEOs be expanded to include NEOs between 30 and 50 m in diameter. NASA's NEO program estimates that "with an average interval of about 100 years, rocky or iron asteroids larger than about 164 ft (50 m) would be expected to reach the Earth's surface and cause local disasters or produce the tidal waves that can inundate low lying coastal areas." A NEO with a diameter of 50 m can create a blast equivalent to one megaton of TNT.

There have not been a significant number of deaths caused by asteroids in historical times due to the infrequency of the major events. When such events do occur they are more likely to happen over unpopulated regions such as oceans. Noting that without better surveys, accurate estimates of the risk of NEO impacts cannot be made, the report made best current estimates for the global risk of death by shark at 3-7 persons per year, death by asteroid at 91 persons per year and death by automobile at 1,200,000 persons per year.