Although the risk of a deadly pandemic was known, the past few months have shown that we could not anticipate it. There is another distant, but almost certain, risk: that of a collision between an asteroid and Earth. A predicted catastrophe whose dimensions could be planetary, like the one that destroyed the dinosaurs some 66 million years ago. To prepare for this, the United States and Europe have designed two complementary space missions. The first to leave, carried by NASA and called DART, successfully took off aboard a SpaceX Falcon 9 rocket from the US base at Vandenberg, Tuesday evening at 10:21 p.m. in Florida, i.e. at 7:21 a.m. in Paris this Wednesday morning.
This mission, composed of a 550 kilogram probe devoid of sophisticated scientific instruments, aims to crash at an approximate speed of 6 km / s on the surface of the moon of the asteroid Didymos, called Dimorphos, whose diameter is about 160 meters. A deliberate collision that is scheduled for fall 2022, about 15 million kilometers from Earth. The objective of this kamikaze mission is to measure the effects of the impact through an observation campaign, carried out by telescopes, from the Earth. This is because the shock should have a visible effect on its orbit around its parent body. After that, the European mission Hera will take off in its turn, in the course of 2026, to go there and see the extent of the damage.
What’s the point ? The aim of the operation is to determine if this technique known as the kinetic impactor indeed allows this type of body to be deviated from its trajectory and can thus constitute an effective weapon in the event of a collision announced with one of the asteroids likely to cross. the trajectory of the Earth. Near-Earth asteroids of which we only know 90 to 95% of those over 1 kilometer in diameter and barely 30% of those 140 to 999 meters. If the operation works and if scientists collect enough data during this test, humanity will already have the beginning of a solution to avert planetary catastrophe. On one condition: you must have seen the event coming soon enough to act!