On September 26th, 2022, a spacecraft the size of a refrigerator, weighing 570 kilograms, crashed into an asteroid traveling at six kilometers per second. Launched by the Falcon 9 rocket, this mission, known as DART, marked a significant milestone in space exploration. Not only did it provide invaluable data, but it also showcased the remarkable engineering and physics behind NASA’s planet defense mission.
Contents
The DART Spacecraft and its Tools
The DART spacecraft itself was designed to be a low-cost vessel focused solely on completing its mission. It carried basic tools such as cameras, star trackers, propulsion systems, antenna systems, and an onboard computer. It had no scientific instruments, as its purpose was to redirect an asteroid rather than gather scientific data.
One exceptional aspect of the DART mission was the video footage captured by a small Italian-made spacecraft released by DART. This footage showed the impact, revealing a massive plume of debris being ejected from the asteroid.
Choosing the Right Target
DART’s target was a moonless asteroid called Dimorphos, which orbits the larger asteroid Didymos. This unique target was selected for its specific characteristics. Dimorphos was passing close to Earth, allowing scientists to measure the impact effectively. Additionally, its orbit allowed for optimal observation of the collision’s results.
To hit the small Dimorphos, DART had to rely on an autonomous navigation system. With a significant lag in communication due to the asteroid’s distance, DART used a camera and a small telescope to calculate the thrust needed to stay on course. This system worked similarly to visual guidance software used in military applications.
DART was equipped with the next generation of ion thrusters called NEXT-C, three times more powerful than previous models. These ion thrusters, powered by lightweight solar cells, were designed to accelerate heavy ions of xenon to extreme speeds. They used an electromagnetic field to achieve speeds of 40 kilometers per second. Although there was a small issue with one of the ion thrusters during flight, it did not impact the mission’s success.
Measuring the Impact and Results
Accurately measuring the impact and its effects from Earth was a significant challenge. Determining changes in trajectory required precise measurements, especially considering Dimorphos was 11 million kilometers away. Scientists turned to binary systems, where a smaller moonless asteroid orbits a larger one. By observing the eclipsing path of the smaller asteroid, scientists could measure changes in its orbit.
Using sensitive telescopes located in the southern hemisphere, NASA timed the patterns of light dimming when Dimorphos passed in front of Didymos. This measurement allowed scientists to determine the change in orbit.
The Success of the DART Mission
After just two weeks of gathering data, NASA announced the mission’s success. The collision with Dimorphos resulted in a change in its orbit by a massive 4.5 percent. The orbit around Didymos decreased from 11 hours and 55 minutes to 11 hours and 23 minutes. These results prove that it is possible to deflect an asteroid if the need arises.
FAQs
Q: What were the tools onboard the DART spacecraft?
A: The DART spacecraft carried cameras, star trackers, propulsion systems, antenna systems, and an onboard computer. It did not have scientific instruments.
Q: Which ion thrusters did DART use?
A: DART used the next generation of ion thrusters called NEXT-C, which were three times more powerful than previous models.
Q: How did scientists measure the impact from Earth?
A: Scientists measured the impact by observing binary systems where a smaller asteroid orbits a larger one. By timing the patterns of light dimming when the smaller asteroid passed in front of the larger one, they could measure changes in its orbit.
Conclusion
The DART mission showcased the incredible engineering and physics behind redirecting an asteroid. With precise autonomous navigation and powerful ion thrusters, DART successfully changed the orbit of the moonless asteroid Dimorphos. This achievement provides valuable knowledge and tools for future planetary defense missions, ensuring our little rock in space is a little safer. To learn more about the fascinating world of space travel and physics, sign up for Brilliance.
