News / Science & Technology

Siberian Blast Points to More Destructive Meteors Ahead

A meteorite contrail is seen over Chelyabinsk, February 15, 2013.
A meteorite contrail is seen over Chelyabinsk, February 15, 2013.
Adam Phillips
— The idea that the orbiting chunks of interplanetary rocks called asteroids could hit the Earth and wipe out cities, or even life itself, is a familiar theme in space-based adventure films. But according to three just-released scientific studies in the journals Nature and Science, the likelihood that dangerous asteroids will enter Earth’s atmosphere may be greater than previously believed.

On February 15 of this year, the world was inundated with dramatic video images of a 19-meter-wide meteor streaking across the sky above Chelyabinsk, Russia at nearly 67,000 kilometers per hour. Well over 1,000 people were injured by the event, mostly from the blinding flash and from broken window glass. Still, according to physicist Paul Wiegert of the University of Western Ontario and an author of a study of the Chelyabinsk meteor just published in the journal “Nature”…  

“… Chelyabinsk didn’t really create as much damage as we might have expected, and that’s a good thing. The flip side is that we are now starting to discover that events like the Chelyabinsk event are occurring more frequently than we had originally anticipated. But we’ll have to wait a little while longer and collect a little more information before we can know for sure," said Wiegert.

Wiegert adds that collecting that information about orbiting asteroids the size of the one that exploded over Chelyabinsk, then determining their path relative to Earth, is a difficult job using conventional earth-based telescopes.  

“Larger asteroids are relatively easily seen with telescopes because they are fairly big. Much, much smaller objects are much more common and frequently hit the earth as meteorites - shooting stars, falling stars and things like that. So we see the bigger objects and we see the smaller objects relatively well. But the Chelyabinsk event kind of falls into the gap between the two," he said.

At a recent panel of the Association of Space Explorers in New York, physicist and former astronaut Ed Lu warned there is little time to lose. He said there are about 10,000 known asteroids orbiting our region of the solar system - that’s just one-thousandth of the number scientists believe could actually be there. Lu's B612 Foundation is planning to help launch a space-based infrared telescope in 2018 that can detect the heat emitted by asteroids, map their position and orbit, then provide a warning in time to mount an international effort to deflect the more dangerous ones.  

“You cannot deflect an asteroid that you haven’t found. And the technology exists, the know-how exists and we realized that the cost of finding and tracking these things, the telescope to do that, is about what it cost to build a large freeway overpass," said Lu.

Paul Wiegert says he’s fascinated by the Chelyabinsk event and would welcome the launch of an infrared space telescope to locate similar asteroids.

“But I don’t think the Chelyabinsk event has really increased our perception of the danger. You won’t have any difficulty finding someone who thinks we should be spending more money looking for more asteroids. But I don’t think anybody in the asteroid community is sleeping any less soundly because of that event," he said.

Nevertheless, officials at NASA’s Near Earth Object program, which scans the heavens for dangerous objects, say the space agency is reassessing what size rocks to look for and how often they are likely to hit.

You May Like

EU Court Fines Poland for Hosting CIA 'Black Sites'

Ruling is first time a court has acknowledged suspects were held and tortured at the sites, under US program launched following the 9/11 terrorist attacks More

Migrant Issues Close to Home Spur Groups to Take Action

Groups placing water, food in the desert, or aiding detainees after release, have one common goal: no more deaths of migrants crossing illegally into the US More

Video At AIDS Conference, Prevention Pill Stirs Excitement

Truveda shows promise, spurring debate over access and other approaches More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Treatment for Childhood Epilepsy Heats up Medical Marijuana Debatei
X
Shelley Schlender
July 24, 2014 6:43 PM
In the United States, marijuana is classed as an illegal drug by the federal government. But nearly half the states have legalized it, to some degree. Proponents say some strains of marijuana might have exceptional health benefits, for treating pain or inflammation in chronic conditions such as cancer, multiple sclerosis and epilepsy. Shelley Schlender reports on a strain of medical marijuana developed in Colorado that is reputed to reduce seizures in childhood epilepsy
Video

Video Treatment for Childhood Epilepsy Heats up Medical Marijuana Debate

In the United States, marijuana is classed as an illegal drug by the federal government. But nearly half the states have legalized it, to some degree. Proponents say some strains of marijuana might have exceptional health benefits, for treating pain or inflammation in chronic conditions such as cancer, multiple sclerosis and epilepsy. Shelley Schlender reports on a strain of medical marijuana developed in Colorado that is reputed to reduce seizures in childhood epilepsy
Video

Video Airbus Adds Metal 3D Printed Parts to New Jets

By the end of this year, European aircraft manufacturing consortium Airbus plans to deliver the first of its new, extra-wide-body passenger jets, the A350-XWB. Among other technological innovations, the new plane will also incorporate metal parts made in a 3-D printer. VOA's George Putic has more.
Video

Video Death Toll From Israel-Gaza Conflict Surpasses 700

Gaza officials say a shelling hit a compound housing a United Nations-run school in the Gaza Strip, killing more than a dozen people, during an Israeli offensive in the area. Heavy fighting between the Israeli military and Hamas militants continued on Thursday, pushing up the death toll. So far, more than 730 Palestinians and 35 Israelis have been killed in the conflict. VOA's Scott Bobb has the latest from Jerusalem.
Video

Video AIDS Conference Welcomes Exciting Developments in HIV Treatment, Prevention

Significant strides have been made in recent years toward the treatment and prevention of HIV, the virus that causes AIDS. This year, at the International AIDS Conference, the AIDS community welcomed progress on a new pill that may prevent transmission of the deadly virus. VOA’s Anita Powell reports from Melbourne, Australia.
Video

Video Israel Targets Gaza Supply Tunnels

The Israeli military has launched a ground operation in Gaza to destroy the myriad tunnels that may have been used to smuggle weapons to Hamas. VOA's Zlatica Hoke reports that could mean more hardship for the people of Gaza, who obtain some of their essential supplies through these underground passages
Video

Video Researchers Target Low-Cost Avatar Technology

Scientists at the University of Southern California Institute for Creative Technologies say 3-dimensional representations could revolutionize social media. Elizabeth Lee has more from Los Angeles.
Video

Video IAEA: Iran Turns its Enriched Uranium Into Less Harmful Form

Iran has converted its stockpiles of enriched uranium into a less dangerous form that is more difficult to use for nuclear weapons, according to the United Nations’ Atomic Energy Agency. The move complies with an interim deal reached with Western powers on Iran's nuclear program last year, in exchange for easing of sanctions. Henry Ridgwell reports for VOA from London.
Video

Video In Cambodia, HIV Diagnosis Brings Deadly Shame

Although HIV/AIDS is now a treatable condition, a positive diagnosis is still a life altering experience. In Cambodia, people living with HIV are often disowned by friends, family and the community. This humiliation can be unbearable. We bring you one Cambodian woman’s struggle to overcome a life tragedy and her own HIV positive diagnosis.

AppleAndroid