- DART is a planetary defense-driven test of technologies for preventing an impact of Earth by a hazardous asteroid.
- Under this NASA launched a mission in Nov 2021, aboard Space X Falcon 9 rocket. It sent a space capsule of the size of a fridge towards an asteroid to shoot it off course. The target asteroids were 11 million kms away from Earth and DART mission reached here after 11 months of journey.
- DART’s test target was an asteroid (Diomorphos/Didymos B) that passed the earth in 2022 and will come back two years later.
- It’s primary body (Didymos A) is 780 meters across, its secondary body (or “moonlet”) – Didymos B is about 160 meter in size, which is more typical of the size of asteroids that could pose the most likely significant threat to Earth.
- NOTE: DART’s target asteroid was NOT a threat to earth, and it is only a test mission.
- In Sep 2022, this space capsule was crashed into Dimorphous/Didymos-B.
- It used autonomous targeting, using images of the asteroids it acquires as it approaches. DART needed to recognize the asteroid itself, automatically lock onto Dimorphous, and adjust its trajectory to hit it. This is while it was moving at a speed of 24,000 km per hour.
Aim of the project: Prepare to save earth from future threat of asteroids.
- DART is the first mission to demonstrate the Kinetic Impactor Technique – striking the asteroid to shift its orbit – to defend against potential future asteroid impact.
Aim of this test: Evaluate weather Kinetic Impactor technique can be used to deflect an object (Dimorphous/Didymos B) from its orbit.
Why Didymos system was chosen?
- Because it is a binary pair, it will be possible for astronomers on Earth to assess the results of the impact.
- These asteroids post no risk to Earth and have been chosen as the target for partly due to that fact.
How observations were made:
- Measurements from telescopes on Earth.
- LICIACube: It is an Italian Space Agency CubeSat (a small type of satellite) that was deployed from a spring-loaded box aboard the craft on 11th Sep. LICIACube followed along and photographed the collision and its aftermath.
- For the first time, human has changed the orbit of a planetary body. The impact shortened Dimorphos’ orbit time by 32 minutes.
- Proof: The test was a proof of concept for many technologies, that NASA has invested over the last few years.
- DART has also given some fascinating data about both asteroid properties and the effectiveness of a kinetic impactor as a planetary defence technology.