A spacecraft that plowed into a small, harmless asteroid millions of kilometers from Earth managed to change the space rock’s orbit, NASA said Tuesday, announcing the results of its first such test .
The US space agency strategically launched the Double Asteroid Redirection Test (Dart) spacecraft into the path of the asteroid, knocking it off course.
NASA hopes to be able to deflect any asteroid or comet that poses a real threat to Earth.
NASA Administrator Bill Nelson, a former astronaut and Florida Democratic senator, said, “We have shown the world that NASA is serious about being a defender of this planet.”
Lori Glaze, director of NASA’s planetary division, said, “Let’s all take a moment to soak it in. We’re all here this afternoon because, for the first time, humanity has changed the orbit of a planetary body.”
“I am absolutely delighted with today’s announcement of the orbital period change due to the Dart impact,” said Cristina Thomas, Dart principal investigator. “I am constantly impressed by this team and the phenomenal observations they were able to collect in the two weeks after impact. Our team has been preparing for these observations for years as we worked to understand the orbital period leading up to the impact. ‘impact and this result is a testament to how prepared we were for this moment.’
Two famous NASA telescopes, Webb and Hubble, captured the moment the spacecraft collided with the lunar asteroid on September 26. It took days of observation to determine how much the impact altered the 525-foot asteroid’s path around its companion, a much larger rock.
In a statement after the test, NASA said that Dart “intentionally crashed into Dimorphos, the asteroid moon of the Didymos double asteroid system. It was the world’s first test of the mitigation technique kinetic impact, using a spacecraft to deflect an asteroid that poses no threat to Earth and modifying the object’s orbit.
“Dart is a test to defend Earth against potential dangers from asteroids or comets,” the space agency said.
Dart altered the orbit of the asteroid Dimorphos in 32 minutes. Glaze said the minimum requirement to change the orbital period was “really only 73 seconds.”
Glaze noted, however, that if a future asteroid were to threaten Earth, work on the deflection would have to start well in advance: with the Dart mission having only resulted in a 4.5% change in orbit time, “the more time we have for this little push… the better off we are”.
The Dart spacecraft, launched last year and about the size of a vending machine, was destroyed when it hit the asteroid 7m away at 14,000mph, NASA said.
On Tuesday, public figures were quick to congratulate Nasa on the success of the test, which cost $325 million.
In a tweet, Vice President Kamala Harris said: “Congratulations to the NASA team for successfully altering the orbit of an asteroid. The Dart mission is the first time humans have changed the motion of a celestial body in space, demonstrating technology that some day could be used to protect the Earth.”
Scientist and educator Bill Nye said: “We’re celebrating… because a mission like this could save the world.”