Kinetic impactor technology successfully altered the orbit of the asteroid Dimorphos by approximately 33 minutes during a September 2022 test, according to NASA.
How the DART Mission Proved Kinetic Impactors Work
In September 2022, NASA intentionally crashed the Double Asteroid Redirection Test (DART) spacecraft into Dimorphos, a small moonlet orbiting the larger asteroid Didymos. According to NASA, the primary goal of the high-speed collision was not to obliterate the target, but to test whether human technology could successfully alter the path of a celestial body.
Data recorded after the impact showed that the spacecraft’s kinetic force shortened the time Dimorphos takes to complete an orbit around Didymos by about 33 minutes. While that shift in speed and trajectory appears minor, scientists note that a small nudge given early enough can cause a dangerous asteroid to completely miss Earth over a long journey through space. However, researchers stress that understanding an asteroid’s precise mass, shape, internal structure, and surface composition is vital for calculating the exact effectiveness of a kinetic impact.
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The Role of ESA’s Hera Mission and NEO Surveyor
To build upon the data gathered by NASA, the European Space Agency (ESA) is developing the Hera mission. According to ESA, the upcoming spacecraft will conduct a detailed survey of the Didymos and Dimorphos system to measure the crater left by DART and analyze the physical properties of the asteroid pair. This follow-up survey aims to transform the initial experiment into a reliable, repeatable planetary defense technique.
NASA emphasizes that planetary defense strategies rely heavily on early detection systems. To address hard-to-find objects with dark surfaces that reflect very little light, NASA is developing the NEO Surveyor, a dedicated space telescope designed to discover and characterize near-Earth objects that pose potential collision risks.
Frequently Asked Questions
What is a kinetic impactor?
A kinetic impactor is a spacecraft designed to crash into an asteroid at high speed, transferring momentum to give the asteroid a small push and alter its orbital trajectory over time.
Did the DART mission destroy the asteroid?
No. According to NASA, DART did not destroy Dimorphos; it successfully altered the moonlet’s orbit around Didymos by approximately 33 minutes.
Why is early detection necessary for asteroid deflection?
NASA notes that an asteroid must be detected far in advance of a potential impact so scientists have enough time to calculate its trajectory, plan a deflection mission, and allow the small course change to safely steer the object away from Earth.
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