In June 2018, astronomers spotted a small asteroid cataloged as 2018 LA just hours before it smacked into Earth’s atmosphere, with small fragments making it all the way to the ground in Botswana.
Now, new research suggests those little bits of space rock may have originated from one of the more famous small objects in the solar system.
“Combining the observations of the small asteroid in space with information gleaned from the meteorites shows it likely came from Vesta, second largest asteroid in our Solar System and target of NASA’s DAWN mission,” says SETI Institute meteor astronomer Peter Jenniskens.
Nearly two dozen meteorites were recovered from inside the Central Kalahari Game Reserve. Scientists say they represent a rare opportunity to study samples from space that were also observed as they sped towards impact with our planet.
“This was only the third time in history that such an early observation and prediction was possible and only the second time a fragment was recovered,” Alexander Proyer, Professor of Petrology at Botswana International University of Science and Technology, said at the time in 2018.
After almost a week of searching on the ground, the first meteorite fragment was found. Twenty-two more samples were later found and shipped to Finland for analysis. The results, along with studies of the small asteroid’s orbit before impact, found that the samples likely have an origin story that can be traced to Vesta.
“Billions of years ago, two giant impacts on Vesta created a family of larger, more dangerous asteroids,” Jenniskens says. “The newly recovered meteorites gave us a clue on when those impacts might have happened.”
It isn’t as though the small asteroid broke away from Vesta last year and immediately struck our planet. Analysis done in Switzerland and the US suggests that the rock had been floating around space on its own for roughly 20 million years before it decided to tangle with our atmosphere.