Before the DART impact: LICIACube - The Light Italian Cubesat for Imaging of Asteroids

Introduction: In late September 2022 the NASA mission DART will perform the first test of the kinetic impactor technique conceived to deflect an asteroid en route to Earth. With a mass of 650 kg and an impact velocity of about 6.6 km/s, DART is expected to change the binary orbital period of Dimorphos, the 160-m moon of Didymos Near-Earth Asteroid (NEA), by about 10 min, an effect that can be easily measured by ground-based telescopes [1] [2].LICIACube: LICIACube (Light Italian Cubesat for Imaging of Asteroids) is the first purely Italian spacecraft to be operated in deep space. It is a 6U cubesat platform developed by the Argotec company and managed by the Italian Space Agengy (ASI) with the aim to contribute in the NASA DART Planetary Defence objective and to perform autonomous science at the asteroid [3]. LICIACube has been launched together with DART on November 2021: after a 10-months interplanetary cruise it will be released 10 days before the foreseen DART impact on Dimorphos and it will be guided along its fly-by trajectory with a closest approach (CA) of around 55 km from the Dimorphos' surface (Fig. 1). Figure 1 - The nominal LICIACube missionLICIACube is equipped with two different payloads named LEIA (Liciacube Explorer Imaging for Asteroid) and LUKE (Liciacube Unit Key Explorer) (Fig. 2). High-resolution images, obtained by LEIA at the CA (up to 1.5 m/px) will allow us to study the surface morphology of Dimorphos and the presence of boulders/large blocks on its surface. The LUKE data (up to 8 m/px at CA, with a RGB filter system) will give us also the opportunity to investigate the composition of Dimorphos throughout spectrophotometric analyses. It will then be possible to map the surface composition of the object and to derive the surface heterogeneity at the observed scale.After imaging the DART impact, during the fly-by the two instruments will allow us to investigate the nature of the target, explore the difference between the impact and non-impact regions, and to study the nature and the evolution of the produced plume, in order to deeply investigate the composition and the structure of the material composing a small double NEA.Figure 2 - LICIACube and its payload After the Dimorphos fly-by, LICIACube will download the obtained images directly to Earth: the LICIACube Ground Segment has a complex architecture based on the Argotec Mission Control Centre, antennas of the NASA Deep Space Network and data archiving and processing, managed at the ASI Space Science Data Center.Acknowledgements: The LICIACube team acknowledges financial support from Agenzia Spaziale Italiana (ASI, contract No. 2019-31-HH.0 CUP F84I190012600).References: [1] Rivkin A.S. et al., (2021) PSJ, in press. [2] Cheng A. F., et al. (2018) PSS, 157, 104. [3] Dotto E., et al. (2021) PSS 199, 105185.