Speaker
Description
Satis is an ESA planetary defence mission study. The mission consists of a stand-alone 12U-XL CubeSat that aims to rendezvous with a Near-Earth Object (NEO). Satis serves as pioneer to demonstrate a completely new class of small, fast-response missions for planetary defense. Here, we present the Satis mission and its science and planetary defence objectives.
The main objectives of the mission is to characterize a NEO closely. The interior structure of such an asteroid carries the imprint of its collisional and accretion history and is important for planetary defense mitigation attempts and Hypothetical impact assessment [1]. Satis aims to perform detailed characterization of basic physical parameters relevant to planetary defence; interior structure, surface properties and the dynamical state.
The feasibility of the Satis mission concept was studied by an ESA CDF study [2] and since then the mission and system design further advanced [3]. The mission concept is built on a stand- alone CubeSat. The mission starts on a dedicated micro-launcher equipped with a kick stage. The kick stage will be used to inject the CubeSat onto the required escape velocity vector. Following commissioning, the CubeSat will use a high-performance miniaturized electric propulsion system for the interplanetary transfer to achieve the rendezvous with Apophis. The mission duration will cover operations close to the asteroid up to six months. Proximity operations will lead the spacecraft very close to enable detailed analysis of the asteroid. Communication and navigation will be performed using a miniaturized X-band transponder interfacing with ESTRACK deep space ground stations. The payloads considered include a visual camera, thermal imager, radio science experiment as well as Hyperspectral, VIS/NIR imagers to fulfil the science objectives.
Satis Phase A study including Mission Definition and Preliminary Requirements Reviews was successfully completed in the last quarter of 2024 and the Phase B will start in 2025. The target of Phase A study, Apophis encounter with Earth would enable the direct observation of changes in the asteroid’s rotation, possible surface changes, as well as its long-term orbit. Satis would observe these parameters to assess the effects of an Earth close encounter to better characterize the NEO and the evolution of asteroids. During the Phase B study, a fast NEO characterization mission will be considered also without a close encounter and alternative targets, especially other Potentially Hazardous Asteroids (PHA) [4]. The preliminary study identified few hundred potential targets compatible with the Satis mission launch and orbital parameters from the Minor Planet Center database. During the phase B Study these potential targets will be further studied along the mission and payload studies.
References: [1] Senel C. and Karatekin Ö. 8th IAA Planetary Defence Conference, 3-7 April, 2003, Vienna. [2] Satis CDF study (2022) ESA-TECSYE-HO-2022-003030. [3] Fogliano, V. et al. (2024) Small Satellites Systems and Services (4S) Symposium, 27-31 May, 2024, Palma de Mallorca. [4] Karatekin, Ö. et al. (2024) Europlanet Science Congress 2024 Vol. 17, EPSC2024-249.