NASA’s OSIRIS-REx spacecraft recently dropped off precious cargo — sending a sample it collected from asteroid Bennu tumbling through Earth’s atmosphere to land in the Utah desert. A team quickly scooped up the sample and took it for analysis, enjoying the bounty of the largest-ever sample collected from an asteroid.
But the spacecraft didn’t land on Earth along with the sample. Rather, it released the sample as it passed by Earth and continued its journey. Though the spacecraft only had the ability to collect one sample, it still has a whole suite of scientific instruments on board. So rather than letting that go to waste, the spacecraft will now be traveling on to investigate another asteroid. Its new mission is also marked with a new name: the spacecraft is now OSIRIS-APEX.
The spacecraft will now travel to visit asteroid Apophis, which is famous as a near-Earth asteroid that was once thought to be in danger of impacting planet Earth. More recent measurements have shown that we aren’t in danger of an impact any time soon, but the asteroid will still be passing close to our planet.
“Apophis is an infamous asteroid,” said new principal investigator for the OSIRIS-APEX mission, Dani DellaGiustina of the University of Arizona, in a statement. “When it was discovered in 2004, there was a scare that it was going to impact the Earth in 2029, but that risk was retired. Then there was another scare that it was going to impact the Earth exactly seven years later, in 2036, but observations combined with modeling now show that Apophis doesn’t pose a risk for at least the next one hundred years. Despite this, Apophis still has this role in the psyche of all of us who study these things. While it’s not going to impact the Earth in 2029, however, it does get very close.”
OSIRIS-APEX will meet up with Apophis during the period when it will come within 20,000 miles of Earth in April 2029. The asteroid is around 340 meters wide, and asteroids of this size only come this close to Earth around once every 7,500 years. It is thought to be an S-type asteroid, meaning it is made of silicate or stony materials, like the asteroid Bennu. The researchers want to learn about how strong and dense the asteroid is, which is important both for future planetary defense planning and for understanding how asteroids were created and evolve.
By combining data on Bennu and Apophis, researchers can learn more about asteroids that might threaten Earth one day. “We learned a lot at Bennu, but now we’re armed with even more questions,” said Amy Simon, OSIRIS-APEX mission project scientist.
