NASA DART (Double Asteroid Redirection Test) Imagery Shows Change in the Orbit of Target Asteroid
Analysis of data obtained by NASA's DART investigative team over the last two weeks shows that the spacecraft's kinetic impact with its target asteroid, Dimorphos, successfully changed the asteroid's orbit.
This is the first time that humanity has deliberately changed the motion of a celestial object, and the first full-scale demo of asteroid deflection technology.
Images such as those given in the next pages helped scientists in understanding the orbital change caused by DART's impact...
1. This image, from the LUKE camera on ASI’s LICIACube, was captured on Sept. 26, 2022, just after the impact of NASA’s DART, spacecraft with the asteroid Dimorphos.
This image clearly shows the ejection of material streaming off of Dimorphos due to the impact.
2. This image was acquired by ASI's LICIACube satellite just before its closest approach to the Dimorphos asteroid after the DART mission purposefully made an impact on September 26, 2022.
Didymos, Dimorphos, and the plume coming off of Dimorphos after DART impact are clearly visible.
3. In this image, it is possible to observe the Didymos and Dimorphos from a different perspective, which can be useful to determine the shapes of the asteroids.
4. This image, taken by the SOAR Telescope in Chile, shows a side view of the streams of material from Dimorphos' surface. It was captured two days after the asteroid was deliberately impacted by NASA's DART spacecraft.
The material on the right is forming a more than 6,000-mile-long comet-like tail, forced into shape by pressure from the Sun's radiation.
5. This NASA's Hubble Telescope image from Oct. 8, 2022, shows debris blasted from Dimorphos' surface 285 hours after the asteroid was purposely impacted by NASA's DART spacecraft on Sept. 26.
That tail's shape has changed over time. In order to better understand the asteroid, scientists are continuing to study this material and how it moves in space.
6. This image, about a week after the DART impact, depicts a highly magnified view of how Dimorphos' orbit around Didymos is seen from Earth.
Each time around the orbit, Dimorphos passes through the Didymos' shadow, and after half an orbit, casts a shadow onto Didymos. Telescopes, in reality, can see only the combined light from both asteroids.
The graph depicts how the total brightness dips slightly when one body casts a shadow on the other. The new period of the orbit is determined by DART astronomers by measuring the time intervals between the dips that mark these eclipse events.
7. DART team used this chart to determine the orbit of Dimorphos after impact. The new observations show the Dimorphos eclipses occur at different times (green arrows) than if the period were unchanged (gray arrows).
The observed declines in relative brightness for each night’s dataset correspond to Dimorphos eclipses from a new orbital period of 11 hours and 23 minutes, revealing that the eclipse timing differs from the pre-impact period of 11 hours and 55 minutes.
8. Left: Goldstone observations from Oct. 4, 2022.
Right: Combined Goldstone and Green Bank observations from Oct. 9, 2022
8. The bright line across the middle of these images, shows the asteroid Didymos. The images are views of the Didymos and Dimorphos binary asteroid systems.
9. Yellow box shows the asteroid Didymos.
Left: Goldstone observations from Oct. 4, 2022.
Right: Combined Goldstone and Green Bank observations from Oct. 9, 2022
10. Green circle shows the location of the Dimorphos asteroid, which orbits the larger asteroid, Didymos, seen here as the bright line across the middle of the images.
11. Blue circle shows where Dimorphos would have been had its orbit not changed due to NASA’s DART mission purposefully impacting the smaller asteroid on Sept. 26, 2022.
12. The images show a series of radar images of the Didymos and Dimorphos binary asteroid system captured at different times on Oct. 9, 2022.
Dimorphos, the smaller of the two asteroids, is in Green circle. Didymos is seen as the brighter stripe across the middle.
13. This image shows the plumes of ejecta streaming from the Dimorphos asteroid after NASA’s DART, mission, made an impact with it on Sept. 26, 2022.
Each rectangle represents a different level of contrast in order to better see the fine structure in the plumes. By studying these streams of material, we will be able to learn more about the asteroid and the impact process.