How to Use a DART to Get Rid of an Asteroid

Remember that really old 1998 movie Armageddon. You know, the movie where there is an asteroid that is hurtling itself towards Earth and they save the Earth by nuking the asteroid. Yup, that's an actual movie. Starring Bruce Willis. But that is not the point. Asteroids are potentially dangerous to us. While there is a small chance, there is still a chance that an asteroid may collide with Earth. And we don’t want to be the second coming of the dinosaurs. That is why NASA, with help from the ESA and JAXA, has developed the Double Asteroid Redirection Test, or DART.

Render of DART Making Its Approach
Towards the Didymos Asteroid System

DART’s main objective is simple: DART will deliberately crash into the double asteroid Didymos to test whether there would be any effect of a spacecraft impact on the trajectory of an asteroid. DART was first thought of by the ESA and NASA after they struck a collaboration called the Asteroid Impact and Deflection Assessment (AIDA). It entered a conceptual stage in June of 2017 and an assembly phase in August 2018. DART will be launched from Vandenberg Space Force Base onboard a Falcon 9 rocket on November 24, 2021, at 0658 GMT and is predicted to make contact with the asteroid pair Didymos on October 2, 2022.

DART in Falcon 9 
Encapsulation Payload

As you can probably infer, SART has no scientific payloads other than sensors to track the Sun and cameras. Based on information from the sensors, it will be able to autonomously navigate along its trajectory to hit Didymos. DART will make the impact traveling at 6.6 km/s to result in a velocity change of 0.4 mm/s. While this may seem like a minuscule amount, it will result in an extremely large shift in the trajectory of the asteroid system. The estimated velocity change on Dimorphous, the second asteroid in the Didymos pair, is about 0.5 mm/s. To get an accurate reading on velocity change and orbital shift, a smaller spacecraft named Hera would do a detailed reconnaissance and assessment.

DART will utilize NASA’s Evolutionary Xenon Thruster-Commercial (NEXT-C) ion driver. NEXT-C will use electricity generated by DART’s solar panels to create an electric field. This electric field accelerates charged xenon ions to extremely high speeds to propel the spacecraft. Theoretically, ion drives can achieve much higher speeds than traditional, propulsion rockets. DART will be the first spacecraft to test this type of system in space. Ion drives have been used before, but they haven’t been as strong, with NEXT-C being three times stronger than other ion drives. However, it’s not its main method of propulsion.

NEXT-C Ion Drive

DART is also demonstrating Transformational Solar Array Technology which is super-efficient solar cells and can provide three times more power than current solar power technology. The spacecraft is using a Roll-Out Solar Array, similar to what is on the ISS. DART is also the first spacecraft to use a new type of high gain communication antenna called a Spiral Radial Line Slot Array (RLSA). This antenna operates at the X-band Deep Space Network (DSN) frequencies of 7.2 and 8.4-GHz.

LICIA Cube

Another satellite is piggyback riding on DART called the Light Italian CubeSat for Imagine Asteroids or LICIA Cube for short. LICIA Cube is a 6-unit Cubesat made by the Italian Space Agency that will carry out an observational analysis of the Didymos system. It will communicate with Earth directly and will continue to send images to Earth even after DART makes an impact with Didymos.

The DART mission will be instrumental to the fate of mankind and may prove that we will be able to stop an Armageddon-like situation without nukes. Remember, don’t miss the launch of DART, leaving Earth later tonight a little before 11 pm. And mark October 2, 2022, on your calendars.

Trajectory of DART (in pink)

Sources:

“Armageddon (1998 Film).” Wikipedia, Wikimedia Foundation, 23 Nov. 2021, https://en.wikipedia.org/wiki/Armageddon_(1998_film). 

“Double Asteroid Redirection Test.” Wikipedia, Wikimedia Foundation, 23 Nov. 2021, https://en.wikipedia.org/wiki/Double_Asteroid_Redirection_Test. 

“LICIACube.” Wikipedia, Wikimedia Foundation, 23 Nov. 2021, https://en.wikipedia.org/wiki/LICIACube. 

Rao, Rahul. “NASA's Asteroid-Slamming Mission Will Test New Ion Drive System.” Space.com, Space, 22 Nov. 2021, https://www.space.com/dart-mission-test-next-c-ion-drive-propulsion.