In Autumn 2022, the NASA Double Asteroid Redirection Test Mission (DART) will impact the surface of asteroid Dimorphos, a ~165 m body orbiting around asteroid (65803) Didymos, with the main aim to demonstrate the kinetic impactor technique for Planetary Defense. During the last minutes of the mission, the DRACO scienti c camera onboard DART will image the surface of both the primary and the secondary asteroids at different spatial scales, allowing the detection of boulders larger than 0.6-1.5 m on the impacted side of Dimorphos and larger than 11-21 m on Didymos. To complement such observations, the ASI "Light Italian Cubesat for Imaging of Asteroids" (LICIACube) will be released from DART ten days before the impact and will be then autonomously guided through a yby with closest approach distance of 55 km from Dimorphos. Through the LEIA (LICIACube Explorer Imaging for Asteroid) narrow angle camera, it will be possible to safely witness the DART redirection test in situ, while its crater and the ejecta and plume are being formed. At closest approach LEIA will image Dimorphos at ~2 m/px: we will therefore be able to identify all boulders larger than 4-7 m located on the imaged side of the asteroid. The analysis of the boulder surface densities and size frequency distributions (SFD) on Didymos and Dimorphos will be important to understand the processes that originated them (impact cratering versus parent body disruption). In addition, we will compare the SFD derived on the binary asteroid with those obtained on other S-type or carbonaceous minor bodies, highlighting the similarities and differences. In this work, the results of the boulder SFD expected from both LICIACube and DART images are presented. Acknowledgments: This research was supported by the Italian Space Agency (ASI) within the LICIACube project (ASI-INAF agreement AC n. 2019-31-HH.0).
Surface densities and boulders size-frequency distribution on binary asteroid (65803) Didymos- Dimorphos
Alessandro Rossi;
2020
Abstract
In Autumn 2022, the NASA Double Asteroid Redirection Test Mission (DART) will impact the surface of asteroid Dimorphos, a ~165 m body orbiting around asteroid (65803) Didymos, with the main aim to demonstrate the kinetic impactor technique for Planetary Defense. During the last minutes of the mission, the DRACO scienti c camera onboard DART will image the surface of both the primary and the secondary asteroids at different spatial scales, allowing the detection of boulders larger than 0.6-1.5 m on the impacted side of Dimorphos and larger than 11-21 m on Didymos. To complement such observations, the ASI "Light Italian Cubesat for Imaging of Asteroids" (LICIACube) will be released from DART ten days before the impact and will be then autonomously guided through a yby with closest approach distance of 55 km from Dimorphos. Through the LEIA (LICIACube Explorer Imaging for Asteroid) narrow angle camera, it will be possible to safely witness the DART redirection test in situ, while its crater and the ejecta and plume are being formed. At closest approach LEIA will image Dimorphos at ~2 m/px: we will therefore be able to identify all boulders larger than 4-7 m located on the imaged side of the asteroid. The analysis of the boulder surface densities and size frequency distributions (SFD) on Didymos and Dimorphos will be important to understand the processes that originated them (impact cratering versus parent body disruption). In addition, we will compare the SFD derived on the binary asteroid with those obtained on other S-type or carbonaceous minor bodies, highlighting the similarities and differences. In this work, the results of the boulder SFD expected from both LICIACube and DART images are presented. Acknowledgments: This research was supported by the Italian Space Agency (ASI) within the LICIACube project (ASI-INAF agreement AC n. 2019-31-HH.0).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
