International space experts have been hard at work since Monday trying to save the planet from being hit by a giant, hypothetical asteroid.
Many of the world's leading space researchers and academics are currently assembled in Italy at the International Academy of Astronautics (IAA) Planetary Defense Conference. The conference, held every other year since 2009, features "exercises" to prepare for a potential asteroid catastrophe. At the 2013 conference in Flagstaff, Arizona, the experts failed to save the French Riviera city of Nice from a hypothetical asteroid impact.
This year, in addition to presenting the latest research on "developing deflection and civil defense responses" to asteroids, the experts are discussing a practical experiment that they aim to launch in 2020.
This week's experiment involves a hypothetical asteroid collision that could create a crater up to four miles wide and 1,600 feet deep, generating a 6.8-magnitude earthquake. The scenario would affect an area of about 27,000 square miles — roughly the size of Ireland.
Gerhard Drolshagen, a conference organizer and a senior analyst at the European Space Agency, took a break from saving the Earth to speak to VICE News. He explained that there are three stages to preventing an asteroid impact.
"First, you have to track and monitor asteroids," he said. "Then, you need to calculate the probability of a collision with the Earth, and, finally, you decide what measures to take."
Right now, the favored solution to protect Earth from an impending asteroid collision is to deflect the large space rock rather than blow it up, the tactic Hollywood used in the 1998 movie Armageddon. Experts at the conference who spoke to VICE News estimated that bombing an asteroid would only split the rock into millions of smaller fragments, which would then pelt down on Earth and potentially cause significant damage.
But, as French planetary scientist Patrick Michel, a senior analyst at the National Center of Scientific Research, told VICE News, knocking an asteroid that is hurtling through space off its course toward Earth is easier said than done.
"While methods to deflect [an asteroid] have been explored in theory, they have not yet been tested," Michel said.
The "Asteroid Impact and Deflection Assessment" mission in 2020 will be a joint exercise that involves experts from around the globe, including representatives from NASA, the ESA, the German Aerospace Center, France's Observatoire de la Cote d'Azur, and the John Hopkins University Applied Physics Laboratory.
The group plans to send two spacecraft toward a pair of asteroids called Didymos and Didymoon that orbit a common center of mass, a phenomenon known as a binary asteroid. The twin asteroids are set to come within about 7 million miles — a relatively short distance by space standards — of Earth in 2022.
Didymos is about half a mile wide, and the German group will send a probe in 2020 to measure its trajectory. NASA will then launch a second probe in 2022 — part of a "Double Asteroid Redirection Test" — that will crash into the 600-foot-wide Didymoon at around 100 miles per second.
"The experiment is about planetary defense, but it is also significant from a scientific point of view," Michel said.
It would take an asteroid more than a kilometer wide to cause serious damage to Earth, and, though Michel said there is currently no known risk of impact by an object that size, he noted that many asteroids remain undetected.
The French expert recalled how an asteroid hit the Russian city of Chelyabinsk in 2013 at a speed of 40,000 miles per hour. With a diameter of around 60 feet, the asteroid injured more than 1,000 people and caused major structural damage to the city.
"We can't prepare for all incidents of that type, which occur approximately once every 100 years," Michel said, adding that the probability of an asteroid crashing into a densely populated area is relatively low.
US and European space agencies are very committed when it comes to monitoring celestial bodies, but a NASA report published in September 2014 noted that current research into asteroid tracking is inadequate.
"Although the probability of a meteor 1 kilometer or larger striking the Earth is extremely remote, the consequences of such an impact would be severe," the NASA report said.
The authors cited a May 31, 2013 incident when a "massive" asteroid with a diameter of 2.7 kilometers passed within 5.8 million kilometers of Earth, about 15 times the distance from the Earth to the moon.
"Had an object this size struck the Earth," NASA said, "the resulting debris would likely have contaminated the Earth's atmosphere, causing partial obstruction of sunlight, acid rain, and firestorms."
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Image via JPL-Caltech/NASA