Following the first anniversary of the Chelyabinsk meteor incident, scientists have been pondering how to protect the planet from future incursions of asteroids and meteorites. Scientists are currently considering using nuclear weapons against these giant space rocks.
The Chelyabinsk meteor crash took place on Feb. 15, 2013 in the major Russian city of Chelyabinsk. In a streak of light brighter than the Sun, the meteor flew over the southern Ural region before exploding in a huge airburst over the Russian city. The meteor's explosion was said to be equivalent to 500 kilotons of TNT, which is around 20 to 30 times more powerful than the Hiroshima atomic bomb explosion. The shockwave from the explosion injured over 1,600 Chelyabinsk citizens.
Due to the sheer destructive potential of these near-Earth objects, scientists are busy coming up with a plan of defense referred to as the Asteroid Redirect Mission or ARM. As the name suggests, the plan is to redirect certain near-Earth objects before they become a danger to the planet. While not all near-Earth objects are potentially dangerous, NASA scientists are planning to observe the potentially dangerous ones. Once a potential target has been spotted, scientists plan to capture the asteroid and redirect it to a safe distance from the Earth.
"There are other elements involved, but if size were the only factor, we'd be looking for an asteroid smaller than about 40 feet (12 meters) across," said NASA Near-Earth Object Program senior scientist Paul Chodas. "There are hundreds of millions of objects out there in this size range, but they are small and don't reflect a lot of sunlight, so they can be hard to spot. The best time to discover them is when they are brightest, when they are close to Earth."
An ideal scenario would involve spotting potential dangers while they are still very far away. This will give NASA scientists ample time to prepare to redirect the objects. In a worst case scenario however, scientists may have less than a year to come up with a course of action to stop, redirect or destroy a massive space rock hurtling towards the Earth at blinding speed. In cases like this, scientists are considering using nuclear weapons.
Scientists from the Iowa State University's Asteroid Deflection Research Center (ADRC) have come up with a plan on countering asteroid threats that occur with little warning.
The first part of the plan involves sending up a satellite equipped with a nuclear device. The satellite will then be sent on an interception course where it will slam into a target asteroid at a speed of 6.2 miles per second. Just before impact, the satellite will release the nuclear device installed in the rear section of the satellite. This will provide a small time delay between the impact of the satellite and the nuclear device. Once the satellite hits the asteroid, the impact should create a large crater on the surface of the target body. The nuclear device released earlier should also crash into the crater created by the satellite. The device can then detonate blasting the asteroid into little pieces.
"The overall effect of an explosion under the surface is 20 times larger than an explosion on the surface," says Bong Wie, a professor from the Iowa State University's ADRC. "We have all the technology. We don't need anything new. But we need to engineer, integrate and assemble these technologies. And we need practice."
