Mission analysis activities focus on the preliminary definition of space missions, so as to determine the optimal mission profile to achieve a given objective. The development of specific algorithms and software tools provides comprehensive analysis capabilities to cope with these activities.

Mission analysis addresses the study of launch windows, ascent and re-entry profiles, transfer trajectories and operational orbits, as well as interplanetary navigation aspects. Each field of expertise is directly applicable to a wide spectrum of mission scenarios, such as:

*Earth orbiting missions, mainly GEO and LEO missions (Earth observation, remote sensing and telecommunications satellites).
* Interplanetary missions to a variety of different targets,as plane

ts, natural satellites, Lagrange points asteroids and minorbodies, comprising trajectory design, optimisation and navigation.
*Mission analysis and design of satellite constellations forEarth observation, telecommunications, science and navigation also playan important role.
*Design and optimisation of entry, descent and landingmissions, including planets (Mars), natural satellites (Moon, Titan)and asteroids.

DEIMOS has outstanding presence in the field of mission analysis, leading and participating in a number of programmes and initiatives. As a result, DEIMOS has developed an important know-how in terms of software tools to support the resolution of most of the problems in the domain by using up-to-date techniques, like low thrust propulsion, fuzzy boundaries or manifolds to represent the dynamics around libration points.

Areas of expertise:

DEIMOS expertise in the scope of mission analysis includes the following relevant areas:

• Mission Design and Feasibility: DEIMOS expertise enables to accomplish feasibility studies to assess the possibility of achieving a given mission objective using the available technologies and resources, and taking into account the relevant constraints. Launch window calculation, eclipse analysis, trajectory definition, orbit maintenance, lifetime studies and risk assessment are key issues to be dealt with. Satellite disposal and re-entry analysis are also analysed. Tailored algorithms and software tools are developed to simulate the space environment and its effects on the mission design (celestial mechanics, spacecraft tracking capability, propellant budget). DEIMOS analysis capability covers all the relevant phases of interplanetary mission design. Starting from spacecraft orbit injection, the analyses encompass orbit transfers, escape trajectory definition, interplanetary navigation and manoeuvre computation. Lunar gravity assist, Weak Stability Boundary orbits, multi-body fly-bys, aero-braking phases and rendezvous with deep space bodies (such as comets and asteroids) can be implemented, depending on the specific mission profile. Both chemical and low-thrust propulsion can be considered and modelled.

• Trajectory Optimisation: The experience in this field has been widely demonstrated in several activities, addressing challenging trajectory optimisation problems for planetary and interplanetary mission. The optimisation of launch vehicles ascent profiles and spacecraft trajectories are carried out using ad-hoc optimisation algorithms and numerical methods. Navigation phases and manoeuvre execution are optimised taking into account mission lifetime, propulsion system (chemical or electric) and propellant constraints.

• Interplanetary Navigation: Navigation activities comprise trajectory and orbit determination and the derivation of the required manoeuvres according to a prescribed guidance law. These processes are seen from a statistical point of view to derive an indicative fuel budget and to assess whether the nominal trajectory can be effectively achieved. To do so, DEIMOS has an outstanding expertise, which has been translated into a set of software tools for different mission scenarios, such as electric propulsion missions or libration point missions.