NASA's Double Asteroid Redirection Test (DART) was designed to demonstrate the potential for using a kinetic impactor to deflect the trajectory of a potentially hazardous object, and to investigate the momentum enhancement, beyond that of the spacecraft itself, that is produced by the material ejected in the impact. The DART spacecraft impacted asteroid Dimorphos, the secondary component of the binary asteroid system (65803) Didymos, on 26 September 2022, changing its orbital period by 33±1 (1?) minutes. The successful outcome of the experiment proved the feasibility of the kinetic impactor concept, but to fully understand how the momentum imparted by the ejecta contributed to the changes in Dimorphos' orbit, it is necessary to ascertain the net direction in which the material was expelled. DART's companion spacecraft, LICIACube, observed the aftermath of the event during its post-impact flyby, imaging the complex structures formed by the ejected material, and we are using the parallax imparted by the spacecraft's changing viewpoint to map these structures in three dimensions. LICIACube also detected what appear to be clusters, consisting of dozens of boulders, that were launched in preferred directions. These boulders could represent a notable fraction of the ejecta mass, and determining the directions in which they were emitted could inform on the mechanisms that controlled the impact physics. As part of our ejecta mapping efforts, we will determine the relative positions and velocities of these boulders with respect to Dimorphos, and estimate their contributions to the total momentum yield from the DART impact.
SPATIAL DISTRIBUTION OF THE BOULDERS IN THE DART IMPACT EJECTA: A 3-D ANALYSIS
A Rossi;
2023
Abstract
NASA's Double Asteroid Redirection Test (DART) was designed to demonstrate the potential for using a kinetic impactor to deflect the trajectory of a potentially hazardous object, and to investigate the momentum enhancement, beyond that of the spacecraft itself, that is produced by the material ejected in the impact. The DART spacecraft impacted asteroid Dimorphos, the secondary component of the binary asteroid system (65803) Didymos, on 26 September 2022, changing its orbital period by 33±1 (1?) minutes. The successful outcome of the experiment proved the feasibility of the kinetic impactor concept, but to fully understand how the momentum imparted by the ejecta contributed to the changes in Dimorphos' orbit, it is necessary to ascertain the net direction in which the material was expelled. DART's companion spacecraft, LICIACube, observed the aftermath of the event during its post-impact flyby, imaging the complex structures formed by the ejected material, and we are using the parallax imparted by the spacecraft's changing viewpoint to map these structures in three dimensions. LICIACube also detected what appear to be clusters, consisting of dozens of boulders, that were launched in preferred directions. These boulders could represent a notable fraction of the ejecta mass, and determining the directions in which they were emitted could inform on the mechanisms that controlled the impact physics. As part of our ejecta mapping efforts, we will determine the relative positions and velocities of these boulders with respect to Dimorphos, and estimate their contributions to the total momentum yield from the DART impact.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
