About ESA
The European Space Agency (ESA) is Europe’s gateway to space. Its mission is to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.
Highlights
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Space in Member States
Find out more about space activities in our 23 Member States, and understand how ESA works together with their national agencies, institutions and organisations.
Germany
Austria
Belgium
Denmark
Spain
Estonia
Finland
France
Greece
Hungary
Ireland
Italy
Luxembourg
Norway
The Netherlands
Poland
Portugal
Czechia
Romania
United Kingdom
Slovenia
Sweden
Switzerland
Science & Exploration
Exploring our Solar System and unlocking the secrets of the Universe
Go to topicAstronauts
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Enabling & Support
Making space accessible and developing the technologies for the future
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Optimising spacecraft cruising, landing and exploration
Optimality principles determine the decision-making during different phases of exploration missions. (A) During an interplanetary phase, the spacecraft dynamics are well identified. Uncertainties are limited and the departure from a theoretical mass optimal guidance is of less importance due to the relatively slow dynamics involved. Please note the time scale of the x-axis in years, and the bang-bang profile of the thrust (solid line). The Venus Express spacecraft is here used for visualization purposes [credit: ESA].(B) During a landing phase (here visualized using Apollo’s Eagle module), according to the specific mission profile, the adaptiveness and robustness of the planned actions have a larger effect on the mission success, also considering that human operators are typically too far away to allow re-planning within an acceptable timeframe. Please note the time scale of the x-axis in minutes and the discontinuous actions. C) During a planetary exploration phase (for instance rovers or flying drones) uncertainties are larger and optimality principles such as careful use of available onboard energy need to be embedded into highly disturbed and fast dynamics (time scale in seconds). Depending on the phase of the missions, control systems may have a lot or very little time to recover from errors and cope with noise. The Ingenuity Mars helicopter [credit: NASA/JPL-Caltech] is used for illustration.
