Killer meteors: 'If it's coming in three weeks, pray' (3/20/13)
Scientists testifying before Congress on Tuesday said the effort to find small killer asteroids is behind schedule and there is little that could be done if a large asteroid capable of destroying civilization were detected a few weeks before it collided with Earth.
NASA is leading a global push to find and track these "near-Earth objects." The U.S. space agency is confident it has found 90 percent of near-Earth objects capable of wreaking the kind worldwide catastrophe that occurred 60 million years ago, when scientists believe a large asteroid strike wiped out the dinosaurs as well as thousands of other animal and plant species on the planet. But if there's a mile-wide asteroid bearing down on Earth now, we're apparently doomed.
"The answer to you is, if it’s coming in three weeks, pray," NASA Administrator Charles Bolden told the House Science, Space and Technology Committee.
The effort to find smaller killer asteroids such as the one that exploded over Russia last month and injured more than 1,200 people is behind schedule, Bolden and President Obama's top science adviser testified. "Unfortunately, the number of undetected potential 'city killers' is very large," John Holdren said. "It’s in the range of 10,000 or more."
Congress has directed NASA to find 90 percent of near-Earth objects that are at least as big as a football field by 2020. But Bolden said more money and a new space-based telescope are needed to reach that goal. At the current rate of funding, he said the effort to detect "city killer" asteroids is about 10 years behind schedule.
The B612 Foundation says several years of advanced warning would be required to launch a mission to deflect an approaching killer asteroid: "In general, to deflect an asteroid we would need several years to decades of advance notice. That is because the amount (of energy) you need to deflect an asteroid greatly increases the closer it is to hitting you. In addition, we need a suitable launch window that allows a spacecraft to reach the asteroid."
Meteorite blast over Russia injures about 1,200 (2/15/13)
This shot across Earth's bow left a mark.
Russian officials are reporting a meteorite explosion over the Ural Mountains today has injured about 1,200 people, most suffering cut wounds from windows shattered in the blast. While far smaller that the mid-air meteorite explosion linked to the Tunguska Event in 1908, today's celestial event damaged at least 300 buildings, including the collapse of a metal factory's roof.
The meteorite that exploded this morning, which is estimated to have weighed 10 tons when it entered the Earth's atmosphere, literally shook the city of Chelyabinsk in Russia's Ural Mountains. The Russian Interior Ministry reported that about 1,200 people were injured, including more than 200 children.
Dramatic video of the meteorite explosion was captured on the dash cameras of several Russian motorists. Dash cameras are used widely in Russia because citizens fear encounters with corrupt police officers.
Feb. 15 asteroid flyby should be global wakeup call (2/14/13)
When it comes to celestial objects striking the Earth, size definitely matters.
While the miles-wide asteroid that struck the planet 60 million years ago and wiped out the dinosaurs gets all the headlines, scientists believe smaller chunks of ice and rock are capable of leveling entire metropolitan areas. Earth likely will be spared an explosive encounter with asteroid 2012 DA14 tomorrow, but the planet apparently wasn't so lucky in 1908.
In what is widely known as the Tunguska Event, an asteroid or comet about the size of 2012 DA14, which is about as big as a cruise ship, entered the Earth's atmosphere on June 30, 1908, then exploded several miles above a remote area of Siberia. Millions of trees were flattened in the blast zone, which spanned an 830 square-mile area. The explosion, estimated to be more than 1,000 times more powerful than the atomic bomb dropped on Hiroshima in 1945, knocked people from their feet as far as 40 miles away.
Given the potential for such collisions to wreak cataclysmic destruction, you would think governments around the world would consider these so-called Near Earth Objects a top priority. “It’s like Mother Nature sending a warning shot across our bow,” Don Yeomans, a scientist at NASA's Jet Propulsion Laboratory, said of 2012 DA14 in The Washington Post last week.
It's easy to argue not enough is being done to track Near Earth Objects and to develop technology to alter their course if necessary to protect Earth. Scientists believe they have discovered 95 percent of Near Earth Objects capable of wiping out most terrestial life on the planet. But Near Earth Objects the size of 2012 DA14 are a different story.
"Saying we’re only going to find the civilization-killers is a (sub-par) threshold,” former U.S. astronaut Ed Lu told The Washington Post. “We can do better than that.”
12/12/2012: Planet killer visits Earth
An odd coincidence?
Tons of ink have been spilled and megabytes of server space consumed over the 12/21/2012 prediction of doom in the Mayan calendar. Given the Mayans' sophisticated understanding of astronomy, could they have predicted for today a devastating collision of asteroid 4179 Toutatis and Earth?
Mayan math may have been off a few million miles, but the potential for a cataclysmic asteroid strike on Earth deserves more attention than it gets. Ironically, as various and sundry prognostications of Armageddon spark periodic media frenzies, the search for killer asteroids, from city busters to planet-scorching mountains of spaceborne rock and ice, goes on in the darkness outside the media spotlight.
Understanding the impact of asteroids on the evolution of Earth is a relatively fresh area of science. Speculation over the cause of the Moon's craters raged well into the middle of the 20th century, when geologist Gene Shoemaker solved the mystery at Meteor Crater in Arizona. In the 1950s, Shoemaker proved that the mile-wide, 550-feet-deep gash in the Arizona desert was the result of a meteor strike about 50,000 years ago. Subsequent research, including the Apollo missions to the Moon's surface, proved asteroid strikes have been a feature of planetary evolution in our solar system for billions of years.
Scientists are now studying the possible role of asteroids bringing water and even life to Earth. Where there's life, there's death, and killer asteroids can apparently generate a lot of death.
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