Near-Earth Asteroid risk mitigation strategy in the next decade: from Earth-based facilities to DART and Hera space missions Adriano Campo Bagatin Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías (Universidad de Alicante) Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal (Universidad de Alicante) Planetary defence strategy from NEOs Find & follow From ground, ongoing (~5 new NEOs/day) up NEOs Assess threat From ground, ongoing (NEOCC + SENTRY) Prevent Can only be done in space Kinetic Impactor: most flexible, realistic, tech-ready DART/Hera Validation = Impactor + Rendezvous From the ‘Don Quijote mission’ to the AIDA collaboration The AIDA collaboration (DART, NASA + Hera, ESA): Asteroid Impact and Deflection Assessment Andrea Milani (1848-2019) Don Quijote mission. (ESA, 2003) ESA UNCLASSIFIED - For Official Use DART + Hera target: Binary NEA (65803) Didymos ESA UNCLASSIFIED - For Official Use S type (maybe LL analogue meteorite) LaunchDART outline July 22, 2021 Double Asteroid Redirection Test Falcon 9, VAFB Ballistic Trajectory IMPACT:IMPACT: September September, 30, 20222022 Launch: July 22nd, 2021 LICIACubeLICIACube (Light(Light Italian Italian Cubesat Cubesat forfor Imaging Imaging of of Asteroids) Asteroids) ASIASI contribution contribution 65803 Didymos (1996 GT) DART Spacecraft 1,18065803-m Didymos binary separation 650DART kg arrivalSpacecraft mass DimorphosDidymos-B (1996 GT) Didymos-A 18.8650 kgm × 2.4 m × 2.0 m 163 mmeters 1,180-meter separation 780 m,meters, S-type S-type 6.656.65 km/skm/s closing speed 11.92-hhour orbital orbital period period between centers of A and B 2.26-hhour spin rotation period period Earth-Based Observaciones Earth-Based Observations • Target the binary asteroid Didymos system 0.07 AU range 0.07at impact AU distance to Earth at impact. Predicted ~10-~10minute-min change (~1%) change in• DimorphosImpact orb.Didymos Period.-B and change its orbital period in binary orbit period • Measure the period change from Earth ESA UNCLASSIFIED - For Official Use What will DART provide? 1. First demonstration of KI technique to deflect an asteroid. 2. Test autonomous GNC for hypervelocity impact on 150 m target. 3. Measure Didymoon’s orbital period change due to the DART collision (only from ground observations: e.g. Arecibo). 4. LICIA Cubesat (ASI) to perform ~5-6 min Didymoon fly-by + confirm impact and image ejecta plume. Hera outline Launch: October 2024 Arrival: January 2027 What will Hera provide? Ø Validate DART impact (crater properties/dust environment) Ø Full characterization of the system (mass of components/orbital parameters) Ø Laser ranging to fine shape and size measurement Ø Deployment od 2 cubesats and radio networking A mission of ‘Firsts’ Ø Radio science/gravimeter/accelerometer to constrain • First investigation of a binary asteroid gravity field and internal properties • Smallest asteroid ever visited Ø Hyperspectral imaging of the surface of Dimorphos • First full scale cratering physics experiment Ø Bonus science: • First radar tomography of an asteroid Cratering physics Internal structure • First inter-satellite (cubesats) communication in deep space Binary asteroid formation.