Didymos

asteroid

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Last updated

July 22, 2026

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Didymos is a binary asteroid system, consisting of a larger asteroid named Didymos and a smaller moonlet called Dimorphos. This system gained significant attention due to NASA's Double Asteroid Redirection Test (DART) mission. In September 2022, the DART spacecraft intentionally collided with Dimorphos. The primary goal was to test humanity's ability to deflect an asteroid's trajectory, a crucial aspect of planetary defense. The mission successfully altered Dimorphos's orbit around Didymos, demonstrating a viable method for potentially preventing future asteroid impacts with Earth.12

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Earth impact hazard
Defending Earth from a colliding object
…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 larger change, and even changed Dimorphos’s…
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…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 larger change, and even changed Dimorphos’s…
Read More