Debris produced by DART’s impact on Dimorphos could create Earth’s new meteor shower

A recent study shows that a plume of debris produced by NASA’s Double Asteroid Redirection Test (DART) mission’s impact on Dimorphos in 2022, could reach Mars and Earth within 7 years, creating a new meteor shower.

A new study conducted dynamical simulations of over 3 million particles released due to the impact of DART on Dimorphos on September 26, 2022, shows that the impact of ejecta might reach Earth.

According to scientists, the debris is small in size and poses no risk to Earth at this time. The particles observed in the study were classified into three size categories: 10 cm (3.9 inches), 0.5 cm (0.2 inches), and 30 μm (0.0012 inches). The main simulation explored ejecta velocities ranging from 1 to 1 000 m/s (3 to 3 281 ft/s), while a secondary simulation focused on faster ejecta with velocities from 1 to 2 km/s (0.6 to 1.2 mps).

The study shows that ejecta with launch velocities around 450 m/s (1 476 ft/s) could reach the Mars Hill sphere in 13 years, which is within the observed range. Some ejecta particles launched at 770 m/s (2 526 ft/s) could reach Mars’s vicinity in 7 years.

Meanwhile, ejecta with velocities above 1.5 km/s (1 mps) resulted in a higher flux delivery towards Mars and particles could reach Earth’s Hill sphere. The delivery process is slightly sensitive to the initial observed cone range and driven by synodic periods.

According to the study, the particles that could impact Mars were predominantly in the northern regions of DART’s impact site meanwhile the smaller particles are more likely to reach Earth.

The very largest of these meteoroids would only be the size of a softball. They would be certain to burn up in Earth’s atmosphere, although they might make it through the thinner Martian atmosphere.

Scientists estimated more than 900 000 kg (2 million pounds) of rocks and dust were produced due to DART’s impact and they could produce visible meteors by penetrating the Martian atmosphere. This could last periodically for at least the next 100 years.

“Once the first particles reach Mars or Earth, they could continue to arrive intermittently and periodically for at least the next 100 years, which is the duration of our calculations,” Eloy Peña Asensio, a researcher for the Deep-space Astrodynamics Research and Technology group at Italy’s Polytechnic University of Milan.

“This material could produce visible meteors (commonly called shooting stars) as they penetrate the Martian atmosphere,” Asensio added.

“Our results indicate the possibility of ejecta reaching the gravitational field of Mars in 13 years for launch velocities around 450 m/s, while faster ejecta launched at 770 m/s could reach its vicinity in just seven years. Particles moving above 1.5 km/s could reach the Earth-Moon system in a similar timescale,” Asensio said.

“We were amazed to discover that it is possible for some centimetre-sized particles to reach the Earth-Moon system and produce a new meteor shower,” study’s co-author Josep M. Trigo-Rodríguez from the Spanish Institute of Space Sciences (CSIC/IEEC) said.

The DART mission, conducted by NASA, was the first planetary defense experiment aimed at altering the course of an asteroid through a direct collision. The mission was designed to test whether crashing a spacecraft into an asteroid could change its trajectory—a strategy that might one day protect Earth from potential asteroid impacts.

The target of this mission was Dimorphos, a small moonlet about 160 m (525 feet) in diameter, orbiting the larger asteroid Didymos. DART was launched on November 24, 2021, and successfully impacted Dimorphos on September 26, 2022, at a speed of 22 530 km/h (14 000 mph).

The spacecraft, weighing around 610 kg (1 340 pounds), was equipped with a camera called DRACO, which helped it autonomously navigate toward the target in the final hours before impact. The European Space Agency’s LICIACube, a small companion satellite, was released before the collision to capture images and data of the event and its aftermath.

The mission’s objective was to alter the orbit of Dimorphos, which posed no threat to Earth but served as a perfect test candidate for planetary defense techniques.

Following the impact, scientists measured a significant change in the orbital period of Dimorphos, which was shortened by about 33 minutes. This confirmed that a kinetic impactor could indeed change the trajectory of an asteroid, demonstrating the viability of this technique as a planetary defense strategy.

The significance of the DART mission is twofold. First, it provided critical real-world data on how a kinetic impact can be used to deflect a hazardous object, which is key to protecting Earth from future asteroid threats. Second, it showcased advanced technological capabilities, including autonomous navigation systems that guided the spacecraft to its target with precision.

The success of DART is a major milestone in planetary defense, proving that with enough preparation, humanity could prevent a catastrophic asteroid collision.

References:

¹ Delivery of DART Impact Ejecta to Mars and Earth: Opportunity for Meteor Observations – Eloy Pena-Asensio, Michael Kuppers, Josep M. Trigo-Rodrıguez and Albert Rimola –Astro-ph.EP – September 2, 2024

² DART hits asteroid Dimorphos in the world’s first planetary defense technology demonstration – The Watchers – September 27, 2022

³ NASA’s DART mission may cause first ever man-made meteor shower – The Watchers – July 8, 2020

⁴ Intentional NASA spacecraft collision may have caused meteor shower, study says –WSFA 12 – September 1, 2024

⁵ Over 2 million pounds of space debris caused by NASA mission may create first human-made meteor shower – New York Post -August 31, 2024

⁶ Debris from DART impact could reach Earth – ESA – September 6, 2024

Featured image credit: ESA (stillshot)