The probability that an asteroid of significant size will collide with Earth in the coming centuries is very small. Nevertheless, the risk is there and the potential consequences of such a cataclysm would be considerable, even catastrophic. Several methods of facing this threat have been thought up by scientists and by the international community of space agencies.
The CNES invites you to meet two of its experts and learn more about how this catastrophic scenario is being dealt with, on the technical level and on the political side. Join us next Tuesday, June 16th for the next “Space Tuesday” (and last of this season!).
This article is also available in French: Mardi de l’espace : comment le monde se prépare à une collision avec un astéroïde. It was translated to English by Abby Tabor.
The damage caused in Russia in 2013 by the Chelyabinsk meteor, which was only about 20 meters in diameter, foreshadows what an object several hundreds of meters across could inflict on our planet. If it’s our bad luck to have one of them cross our path, would we be able to prevent a collision?
Yes. Theoretically, it would be possible. “The main challenge lies in predicting the impact sufficiently in advance to have the time to react,” clarifies Jean-Yves Prado, a member of the United Nations working group on near-Earth objects. “We would need at least 10 years to plan an avoidance maneuver. Less than that, and only a destruction approach, maybe with a nuclear weapon, would be possible.” That’s a long way from the few months that Hollywood heroes have to save the planet… The methods, though, sound a little like déjà vu.
Catastrophe films, like Armageddon and Deep Impact, generally draw inspiration directly from the work of scientists, often highlighting the method that is currently in vogue in the scientific community. “Recently, the impact method has been on a roll,” says Jean-Yves Prado. “The process consists of launching a spacecraft to crash into the asteroid, with the goal of slowing down or accelerating its course. That way, you avoid [Earth and the asteroid] being in the same place at the same time.”
How would the world react?
In the case of an asteroid over a kilometer in size, the entire planet would be affected by the disaster. The international community in its entirety would, thus, be concerned.
The political and ethical stakes and challenges involve, in particular, less dangerous smaller objects, but for which impacts are statistically more likely. For example, what would happen if only one region of the planet or country were threatened? Who would be in charge of preparing the mission? Who would pay the bill? For example, “we have to wonder how the international community would react if North Korea were threatened,” says Jacques Arnould, in charge of ethical questions at the CNES. “In a way, the issues are analogous to those related to climate change: To what extent will we become collectively aware of the danger facing us? Are we ready to respond to it collectively, even if the size of the area threatened could vary with to the size of the NEO [near-Earth object]? How will we sustain any action that would necessarily extend over a long period (unless detection of the threat comes late)?”
From the discovery of Apophis, the asteroid that will brush past us in April 2029, to the creation of a UN working group: get a look behind the scenes of space surveillance and safety. Join us next Tuesday, June 16 at 7:30pm CEST (10:30am PDT). We’ll be at the Café du Pont Neuf in Paris and on Twitter at the hashtag #CNEStweetup.