The impact of the DART probe could bring a ‘rain of stars’

September 6 () –

The column of debris ejected into space after the impact in 2022 of NASA’s DART space probe against the asteroid Dimporphos could reach Mars and Earth.

This is shown by the latest model, available on the arXiv preprint server and accepted for publication in The Planetary Science Journal. These are small meteoroids, some the size of a baseball (7.5 centimeters in diameter), that could precipitate and disintegrate in the Earth’s atmosphere, potentially in an observable way, ESA reports.

On September 26, 2022, NASA’s roughly half-ton Double Asteroid Redirect Test (DART) spacecraft impacted the 151-m-diameter asteroid Dimorphos at a speed of approximately 6.1 km/s, shortening its orbit around Didymos by more than half an hour during the first part of an international planetary defense collaboration.

ESA’s Hera probe to launch in October to reach Dimorphos and conduct a “detailed investigation of the impact site,” gathering data on the asteroid’s mass, structure, and composition to turn this kinetic impact method of planetary defense into a well-understood and repeatable technique.

“The impact of DART offers a unique opportunity to investigate the arrival of ejected material to other celestial bodies“, thanks to the fact that we know the impact location as this impact was observed by the Italian LICIACube deployed from DART, as well as by ground observers,” explains co-author and ESA Hera mission scientist Michael Kueppers.

“We simulated the ejecta to match LICIACube observations using three million particles grouped into three size populations (10 cm, 0.5 cm and 30 picometers, or thousandths of a millimeter) moving at velocities between 1 and 1,000 m/s or faster than 2 km/s.”

THEY WOULD ARRIVE IN ABOUT THIRTEEN YEARS

The study’s lead author, Eloy Peña-Asensio from the Department of Aerospace Science and Technology at Politecnico di Milano, explains: “We identified ejection orbits compatible with sending meteorite-producing particles to both Mars and Earth. Our results indicate the possibility of ejecta reaching the Martian gravitational field within 13 years for launch velocities of around 450 m/s, while faster ejecta launched at 770 m/s could reach its vicinity in just seven years. Particles moving faster than 1.5 km/s could reach the Earth-Moon system on a similar timescale.”

“In the coming decades, meteorite observation campaigns will be crucial to determine whether Dimorphos fragments resulting from the DART impact will reach our planet. If this happens, we will witness the first meteor shower of human origin,” he added.

Whether meteoroids head toward Earth or Mars will depend on their position in DART’s conical impact plume: material on its north side is more likely to head toward Mars, while material from the southwest is more likely to reach Earth.

The largest of these meteoroids would be only about the size of a baseball. They would likely burn up in Earth’s atmosphere, although they could pass through the thinner Martian atmosphere.

In any case, it seems that only the smallest particles are likely to reach Earth, since they are the ones that would have been launched at the highest velocities. We cannot yet determine whether these particles will be The size of the asteroid is large enough to produce observable meteors, so it will be essential to continue monitoring the night sky.