AIDA: IMPACT AND DEFLECTION ASSESSMENT MISSION UNDER STUDY AT ESA AND NASA. P. Michel1, A. Cheng2, I. Carnelli3, A. Rivkin2, A. Galvez3, S. Ulamec4, C. Reed2, and the AIDA Team 1Lagrange Laboratory, University of Nice, CNRS, Côte d’Azur Observatory (Observatoire de la Côte d’Azur, CS 34229, 06304, Nice Cedex 4, France; [email protected]) , 2The Applied Physics La- boratory (11100 Johns Hopkins Rd, Laurel, MD 20723, [email protected]), 3ESA HQ (Paris, France, an- [email protected]), 4Deutsches Zentrum fuer Luft- und Raumfahrt (DLR)( , [email protected]).

Introduction: The Asteroid Impact & Deflection easier to measure than would be the case if DART tar- Assessment (AIDA) mission will be the first space geted a typical, single near- asteroid so as to experiment to demonstrate asteroid impact hazard mit- change its heliocentric orbit. It is important to note that igation by using a kinetic impactor to deflect an - the target Didymos is not an Earth-crossing asteroid, oid. AIDA is a joint ESA-NASA mission, which in- and there is no possibility that the DART deflection cludes the ESA Asteroid Impact Mission (AIM) ren- experiment would create an impact hazard. The DART dezvous spacecraft and the NASA Double Asteroid asteroid deflection demonstration targets the binary Redirection Test (DART) mission. The primary goals asteroid Didymos in Oct 2022, during a close approach of AIDA are (i) to test our ability to impact a small to Earth. The DART impact will be observable by near-Earth asteroid by an hypervelocity projectile and ground-based radar and optical telescopes around the (ii) to measure and characterize the deflection caused world, providing exciting opportunities for internation- by the impact. The AIDA target will be the binary as- al participation in the mission, and generating tremen- teroid (65803) Didymos, with the deflection experi- dous international public interest, in the first asteroid ment to occur in October, 2022. The DART impact on deflection experiment. the secondary member of the binary at ~6 km/s will Conclusion: AIDA will return fundamental new alter the binary orbit period, which can be measured by information on the mechanical response and impact Earth-based observatories. The AIM spacecraft will cratering process at real asteroid scales, and conse- monitor results of the impact in situ at Didymos. quently on the collisional evolution of with Current status: Both AIM and DART have been implications for planetary defense, , approved for a Phase A/B1 study, starting in February and near-Earth object science and resource utilization. 2015 for 15 months. Baseline payloads for AIM in- AIDA will return unique information on an asteroid's clude a navigation camera, a (based on DLR strength, surface physical properties and internal struc- MASCOT heritage), a thermal infrared imager, a mon- ture. Supporting numerical simulation studies and la- ostatic high frequency radar, a bistatic low frequency boratory experiments will be needed to realize the po- radar (on the orbiter and on the lander), and some op- tential benefits of AIDA and will be an part of portunity payloads based on standards. AIM is the mission. Various communities will thus be in- conceived as a small and simple platform with no volved and working groups are defined to support the mechanisms providing a flight opportunity to demon- mission studies. strate technologies to advance future small and medi- Additional Information: Support from ESA and um mission. As such, AIM will also demonstrate for NASA is acknowledge. the first time the use of deep-space optical communica- tion. It will allow for the first time accessing direct information on the internal and subsurface structures of a small asteroid, and with DART, determining the in- fluence of those internal properties on the impact out- come. The DART mission will use a single spacecraft to impact the smaller member of the binary near-Earth asteroid Didymos in October 2022. DART uses a sim- ple, high-technology-readiness, and low-cost space- craft to intercept Didymos. DART hosts no scientific payload other than an imager for targeting and data acquisition The impact of the >300 kg DART space- craft at 6.1 km/s will change the mutual orbit of these two objects. By targeting the smaller, 150 m diameter member of a binary system, the DART mission pro- duces an orbital deflection which is both larger and