NASA tests impact asteroid to change its orbit DART tasks,sinceLaunched last NovemberThen, after almost nine months of flying, the Dimorphos, who were already getting closer to their target. NASA announced earlier that the exact time of impact will be at 7:14pm ET on September 26th, which is our September 27th at 7:00am, and will be broadcast live about an hour before impact.
The DART mission is testing one of the methods of “Earth defense”. If an asteroid or comet with a high probability of reaching the earth can be found at a very early stage (a few years ago), its orbit can be slightly changed by impact. Let it eventually avoid Earth. The target of the DART impact is a mini-moon Dimorphos (also nicknamed Didymoon) orbiting an asteroid called Didymos. This small moon is about 160 meters in diameter. Neither it nor Didymos has the risk of hitting the earth, but just happens to be suitable for testing location only.
DART expects that within the next few days its navigation camera, DRACO, should be able to catch Didymos and release a tiny cubesat called LICIACube about 10 days before impact. LICIACube will continue to accompany the DART in the next, but gradually increase the distance to photograph the entire process of the impact from a slightly farther perspective. DART will activate its autopilot system four hours before impact (commands from Earth would be too late due to the speed of light delay) and make final orbit corrections four minutes before impact.
If all goes according to plan, Dimorphos’ orbital period around Didymos will be reduced by about 10 minutes from the current 12 hours.andThe European Space Agency also plans to launch a mission called HERA in 2024which will arrive in the Didymos system in 2027 to make more precise measurements and to see if the impacted Dimorphos system has changed from five years ago.