About 66 million years ago, an asteroid fell to Earth, abruptly changing life on the planet. The most famous victims of the inferno were the dinosaurs, which became extinct afterwards. According to experts, no asteroid of this kind is currently hurtling towards Earth, but what if it does? NASA experts are testing such a scenario with the Double Asteroid Redirection Test (DART) mission. In November 2021, the probe was launched into space, tonight on 27 September at 1.14 a.m. Central European Time it is scheduled to hit the asteroid moon Dimorphos. If the mission is successful, the Brocken should then be on a slightly different orbit. NASA reports on the progress of its asteroid defense test tonight live on its Youtube channel.
The DART mission began on November 24, 2021, when the probe was put on course for Dimorphos with a Falcon 9 rocket from the private space company SpaceX. The asteroid is located about eleven million kilometers from Earth at the time of impact. The chunk with a diameter of about 163 meters orbits the larger asteroid Didymos, which measures about 780 meters, as a mini-moon. If the mission goes according to plan, the cube-shaped DART probe, weighing around 610 kilograms, will crash into the satellite at a speed of 22,000 kilometers per hour. After impact, Dimorphos is expected to orbit around its parent asteroid with a changed trajectory and its twelve-hour orbital period will be shorter by at least 73 seconds. Depending on whether the probe hits the asteroid centrally or laterally, the orbital period could also be delayed by several minutes.
In order to observe the impact, the probe dropped out two small satellites on September 11, which record the events with their cameras. For a more precise investigation, the European Space Organization (ESA) will launch her mission Hera in October 2024. This probe is scheduled to reach the asteroid couple in December 2026.
In the course of the history of the earth, asteroids have always been hit on earth. But the actual number and the position of such celestial bodies that will eventually cross the orbit of the earth can only be estimated: Probably around five million asteroids with a diameter of at least 25 meters, which represent a potential risk. Astronomers have no knowledge of the vast majority of astronomers - after all, of an estimated 4.98 million units. However, experts know the position of around 40 percent of asteroids that are approximately 140 meters tall or larger. An estimated 25,000 such chunks are walking around in relative earth closeness.
