EXPLAINED | NASA DART Mission Is All Ready To Hit Its Target. Know All About It

NASA's Double Asteroid Redirection Test or DART is a spacecraft that will travel at a speed of 24,000 kilometres per hour in order to crash into an asteroid next year

Illustration of the DART spacecraft approaching the Dimorphos and Didymos asteroids | PHOTO: NASA

New Delhi: NASA is all set for a first-of-its-kind mission that will investigate and demonstrate a method of asteroid deflection by changing an asteroid's motion in space.

The Double Asteroid Redirection Test (DART) spacecraft will travel at a speed of 24,000 kilometres per hour to crash into an asteroid next year.  

What Is DART's Target?

The binary, near-Earth asteroid system Didymos is composed of two asteroids, Didymos and Dimorphos. Didymos has a diameter of around 780 metres, and is located at a distance of 487,446,221 kilometers from Earth. Smaller in size, Dimorphos has a diameter of around 160 metres and it orbits Didymos.

This binary asteroid system Didymos is DART's target. 

 DART will impact Dimorphos, aiming to change its orbit within the binary system.

Though the asteroid will pose no threat to Earth, the spacecraft will be made to collide with it to change the asteroid's speed and path, as a test of NASA's ability to achieve a kinetic impact on an asteroid and observe its response, the space agency has said. 

 

An illustration of how DART will impact the orbit of Dimorphos about Didymos | Photo: NASA

How Will DART Work?

When DART impacts Dimorphos, the spacecraft will change the orbit of the asteroid within the binary system. Then, the results of DART's kinetic impact with Dimorphos will be analysed by the DART Investigation Team. The team will use telescopes on Earth to study how much the spacecraft's impact changed the asteroid's motion in space. 

The databases of astronomers consist of highly detailed computer simulations of kinetic impacts on asteroids. NASA will compare the results of DART's kinetic impact with these simulations, and assess the effectiveness of the mitigation approach. 

If the approach proves to be effective, NASA will apply it in future planetary defence strategies. Scientists will also understand the accuracy of the computer simulations and the precision with which they reflect an asteroid's behaviour.

Why Didymos Chosen As DART's Target?

NASA has selected the Didymos asteroid system because it does not pose any threat to Earth, and will serve as the perfect testing ground to see if the intentional crash of a spacecraft into an asteroid is effective in changing its speed and direction. 

If the experiment turns out successful, Earth-threatening asteroids could be deflected in future using the same technique.

 

Technicians lower NASA’s Double Asteroid Redirection Test (DART) spacecraft onto a work stand inside the Astrotech Space Operations Facility at Vandenberg Space Force Base in California | Photo: NASA

DART Mission Objectives

DART is a test of technology, through which NASA intends to assess its ability to achieve a kinetic impact on an asteroid and observe the asteroid's response. The international planetary science community will come together to address the global issue of planetary defence.

• DART will demonstrate a kinetic impact with Dimorphos
• DART will change the binary orbital period of Dimorphos. The binary orbital period or the revolution period is the time an astronomical object in a binary system takes to complete one orbit around the other object in the system.
• Investigation teams will use ground-based telescopes observations to measure the orbital time period of Dimorphos before and after the impact
• NASA will measure how the impact affects Dimorphos, and will also analyse how ejecta is released from the asteroid after the impact.

DART Mission Timeline

October 26: DART was transported from the Astrotech Space Operations Facility to the SpaceX Payload Processing Facility (PPF), which is a part of Space Launch Complex 4 at Vandenberg Space Force Base in California. 

October 27: DART was removed from its container, following which technicians conducted experiments on it to confirm it was in good health.

October 28: For three days, a series of operations were performed. DART was set up, fuelled with hydrazine, pressurised, and cleaned up.

After all operations are complete, DART will be integrated with a payload adapter, encapsulated in a payload fairing, attached to a Falcon 9 rocket, and transported to the launch pad. 

DART is scheduled for launch on November 24, at 1:20 am EST (November 24 at 10:50 am IST), aboard a SpaceX Falcon 9 rocket from Vandenberg Space Force Base.