Asteroid defense mission shifted the orbit of more than its target
Ars Technica • • general
Key Points:
- On September 26, 2022, NASA’s DART spacecraft intentionally crashed into the asteroid moonlet Dimorphos, successfully reducing its orbital period around the larger asteroid Didymos by 33 minutes and demonstrating the kinetic impact method of planetary defense.
- Long-term observations revealed that the DART impact also altered the entire Didymos system’s orbit around the Sun by decreasing its velocity by approximately 11.7 micrometers per second, a small but significant nudge that accumulates over time.
- The impact generated ejecta debris that acted like a rocket plume, doubling the momentum transfer to the system (momentum enhancement factor beta ≈ 2), which contributed to shifting the binary system’s center of mass.
- Analysis showed
