The Hera spacecraft is sent to explore an asteroid

CAPE CANAVERAL, Florida, USA –

A European spacecraft took off on Monday to investigate the site of the cosmic collision.

The European Space Agency’s Hera spacecraft has begun a two-year journey to a small, harmless asteroid that NASA struck two years ago in a dress rehearsal for the day the space rock would threaten Earth. Launched by SpaceX from Cape Canaveral, Florida, the craft is the second part of a planetary defense test that could one day help save the planet.

The 2022 collision of NASA’s Dart spacecraft shortened Dimorphos’ orbit around its larger moon, showing that if a dangerous rock is heading our way, there’s a chance it could veer off course ahead of time.

Scientists are eager to closely study the impacts of the impact to find out how effective Dart was and what changes may be needed to protect Earth in the future.

“The more details we can get, the better, because it could be important for planning a future deflection mission if one is needed,” said Derek Richardson, an astronomer at the University of Maryland.

Researchers want to know whether the Dart (which stands for Double Asteroid Redirection Test) spacecraft left a crater, or perhaps more radically changed the shape of the 500-foot (150-meter) asteroid. Before Darth struck, it looked like a flying saucer, but now it looks like a bean, said Richardson, who was part of Darth’s mission and is helping with Hera.

As a result of Darth’s strike, debris and even stones flew from Dimorphos. The debris trail spanned more than 10,000 kilometers (about 6,200 miles) over several months.

Some rocks and other debris may still be floating around the asteroid, posing a potential threat to Hera, mission director Ignacio Tanco said.

“We don’t really know the environment we’re going to work in very well,” Tanco explained. “But that’s the purpose of the mission, to go there and find out.”

European authorities describe the $400 million (€363 million) mission as an “accident scene investigation.”

According to project leader Ian Carnelli, Hera “returns to the crime scene and receives all the scientific and technical information.”