Fragments of space rock could hit Earth after NASA crashed a probe into a distant asteroid.
The US space agency deliberately set its Double Asteroid Redirection Test (DART) spacecraft on a collision course with the asteroid, Dimorphos, two years ago.
It smashed into the rock at about 15,000mph more than seven million miles from Earth in the first test of mankind’s ability to tackle asteroids which could threaten our planet.
Images of Dimorphous in the aftermath of the collision show debris sent into space, with researchers believing larger boulders could hit Mars in the next few decades.
Researchers have been studying smaller bits of Dimorphos and found many are likely to reach Earth and Mars, according to a study accepted for publication in The Planetary Science Journal.
The experts simulated the initial trajectories and velocities of three million fragments using a NASA supercomputer to crunch data collected by a European Space Agency spacecraft that accompanied DART as it hit Dimorphos.
While the fragments don’t pose a threat to Earth due to their small size – 0.001 inches to four inches – their appearance in Earth’s atmosphere may trigger the first meteor shower caused by human activity.
Researcher, Dr Eloy Peña-Asensio, lead author of the study, told Universe Today: “Their small size and high speed will cause them to disintegrate in the atmosphere, creating a beautiful luminous streak in the sky.”
Smaller fragments might arrive within seven years but will most probably be too small to create shooting stars, but the bigger bits may be seen as they burn up in the Earth’s atmosphere. However, these fragments might not show up for over 30 years, according to the study.
The larger fragments could create a new meteor shower, which the researchers have called the Dimorphids.
Researchers came from the Polytechnic Institute of Milan, the Autonomous University of Barcelona, the Institute of Space Science, the Catalonia Institute of Space Studies and the ESA.
The latest research comes after NASA said in March that another study showed the shape of Dimorphos changed and its orbit shrank after the historic collision.
Dimorphos orbits a larger, near-Earth asteroid called Didymos and before DART’s impact, it was roughly shaped like a squashed ball.
Study lead, Shantanu Naidu, a navigation engineer at NASA’s Jet Propulsion Laboratory in Southern California, said: “When DART made impact, things got very interesting.
“Dimorphos’ orbit is no longer circular. Its orbital period (the time it takes to complete a single orbit) is now 33 minutes and 15 seconds shorter.
“And the entire shape of the asteroid has changed, from a relatively symmetrical object to a ‘triaxial ellipsoid’ – something more like an oblong watermelon.”