Telescopes around the world are observing the moment NASA’s spacecraft intentionally collided with an asteroid in September 2022.
Astronomers used the Very Large Telescope at the observatory in Chile. New results published show detailed images of debris flying away from the impact caused by the Double Asteroid Redirection Test (DART).
The DART spacecraft, weighing about 1,200 pounds (544 kg), slammed into the asteroid Dimorphos at a speed of 13,000 miles per hour (20,921 km/h) in an effort to change the asteroid’s trajectory.
Astronomers used the Very Large Telescope in Chile to monitor the debris cloud created by DART’s impact.
The results indicate that this kinetic impact technology could be used to deflect asteroids that may be on a collision course with Earth. Both Dimorphos and the larger asteroid it orbits, named Didymos, are not a threat to Earth.
The impact of DART was successful, altering the orbital period of Dimorphos around Didymos. However, this experiment, which took place 7 million miles (11.3 million km) from Earth, also released tons of material into space.
Astronomers used the Very Large Telescope to study the aftermath of the event. The lead author of the study, astronomer Cyrielle Opitom from the University of Edinburgh (UK), stated: “Impacts between asteroids happen naturally, but you can never predict them. DART is a truly wonderful opportunity to study a controlled impact, similar to a laboratory setting.”
Opitom and her colleagues monitored the debris cloud formed by the collision for a month using the Multi-Unit Spectroscopic Explorer (MUSE).
The initial cloud of rocks and debris blown off the surface of Dimorphos appeared to be composed of fine particles. Days later, the research team observed other structures in the debris cloud, such as clumps and swirls of larger particles, as well as a long comet-like tail behind the asteroid.
The MUSE instrument allowed researchers to observe the cloud through a spectrum of light to search for identifiable signs of chemicals and gases. However, the team did not detect any signs of water or oxygen.
“Asteroids are not expected to contain significant amounts of ice. Therefore, finding any traces of water would be a real surprise,” Opitom remarked. The research team also kept an eye out for traces of the DART spacecraft itself, including the propellant it used to travel to the asteroid.
“We know it’s a long shot, as the remaining gas in the tanks from the propulsion system will not be substantial. Furthermore, some of it has drifted too far to be detectable by MUSE by the time we began our observations,” the researcher noted.
