NASA confirmed on Tuesday that smashing its DART satellite with the Dimorphos asteroid successfully altered the asteroid’s orbit.
The DART mission, a NASA acronym for “Double Asteroid Redirection Test”, is designed to demonstrate that an asteroid that could cause regional devastation here on Earth can be deflected by intentionally crashing a spacecraft into it.
The DART spacecraft, which is about the size of a large home refrigerator, intentionally collided at roughly 4 miles per second (6 kilometers per second) with the asteroid moonlet Dimorphos (Greek for “two forms”), which orbits a larger asteroid named Didymos (Greek for “twin”).
Nether asteroid poses any threat to Earth.
This marks humanity’s first time purposely changing the motion of a celestial object and the first full-scale demonstration of asteroid deflection technology.
“This mission shows that NASA is trying to be ready for whatever the universe throws at us. NASA has proven we are serious as a defender of the planet,” said NASA Administrator Bill Nelson.
“This is a watershed moment for planetary defense and all of humanity, demonstrating commitment from NASA’s exceptional team and partners from around the world.”
Prior to DART’s impact, it took Dimorphos 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos.
Since DART’s intentional collision with Dimorphos on Sept. 26, astronomers have been using telescopes on Earth to measure how much that time has changed.
Now, NASA’sinvestigation team confirmed the spacecraft’s impact altered Dimorphos’ orbit around Didymos by 32 minutes, shortening the 11-hour and 55-minute orbit to 11 hours and 23 minutes. This measurement has a margin of uncertainty of approximately plus or minus 2 minutes.
Before its encounter, NASA had defined a minimum successful orbit period change of Dimorphos as a change of 73 seconds or more. This early data show DART surpassed this minimum benchmark by more than 25 times.
This just in: The #DARTmission impact is confirmed to have changed the orbit of moonlet Dimorphos around its asteroid Didymos.
— NASA (@NASA) October 11, 2022
“This result is one important step toward understanding the full effect of DART’s impact with its target asteroid,” said Lori Glaze, director of NASA’s Planetary Science Division at NASA Headquarters in Washington.
“As new data come in each day, astronomers will be able to better assess whether, and how, a mission like DART could be used in the future to help protect Earth from a collision with an asteroid if we ever discover one headed our way.”