Dimorphos

asteroid

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July 22, 2026

Quick Summary

Dimorphos is a small asteroid that is part of a binary asteroid system with Didymos. It gained significant attention as the target of NASA's Double Asteroid Redirection Test (DART) mission.12

The primary goal of the DART mission was to test humanity's ability to deflect an asteroid's trajectory. On September 26, 2022, the DART spacecraft intentionally collided with Dimorphos. This impact successfully altered Dimorphos's orbital period around Didymos, demonstrating a key strategy in planetary defense. This event marked the first experimental test of deflecting an asteroid, showcasing a method to potentially prevent future collisions with Earth.12

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asteroid
Spacecraft exploration
…DART collided with the asteroid Dimorphos, which orbits the larger asteroid Didymos. Dimorphos orbited Didymos every 11 hours and 55 minutes. Mission scientists considered success as DART’s impact altering Dimorphos’s orbit by at least 73 seconds; DART shortened Dimorphos’s orbital period to 11 hours and 23 minutes, a much larger…
Read More
…DART collided with the asteroid Dimorphos, which orbits the larger asteroid Didymos. Dimorphos orbited Didymos every 11 hours and 55 minutes. Mission scientists considered success as DART’s impact altering Dimorphos’s orbit by at least 73 seconds; DART shortened Dimorphos’s orbital period to 11 hours and 23 minutes, a much larger…
Read More

Earth impact hazard
Defending Earth from a colliding object
…spacecraft collided with the asteroid Dimorphos, which orbits the larger asteroid Didymos. Dimorphos orbited Didymos every 11 hours and 55 minutes. Mission scientists considered success to be the alteration of Dimorphos’s orbit by at least 73 seconds. DART shortened Dimorphos’s orbital period to 11 hours and 23 minutes, a much…
Read More
…spacecraft collided with the asteroid Dimorphos, which orbits the larger asteroid Didymos. Dimorphos orbited Didymos every 11 hours and 55 minutes. Mission scientists considered success to be the alteration of Dimorphos’s orbit by at least 73 seconds. DART shortened Dimorphos’s orbital period to 11 hours and 23 minutes, a much…
Read More

impact event
…spacecraft collided with the asteroid Dimorphos, which orbits the larger asteroid Didymos. Dimorphos orbited Didymos every 11 hours and 55 minutes. Mission scientists considered success to be the alteration of Dimorphos’s orbit by at least 73 seconds. DART changed Dimorphos’s orbital period to 11 hours and 23 minutes, a much…
Read More
…spacecraft collided with the asteroid Dimorphos, which orbits the larger asteroid Didymos. Dimorphos orbited Didymos every 11 hours and 55 minutes. Mission scientists considered success to be the alteration of Dimorphos’s orbit by at least 73 seconds. DART changed Dimorphos’s orbital period to 11 hours and 23 minutes, a much…
Read More