The European Space Agency (ESA) operates a number of space missions, both individually and in collaborations with other space agencies such as U.S. NASA, Japanese JAXA, Chinese CNSA, as well as space agencies of ESA member states (eg. French CNES, Italian ASI, German DLR, Polish POLSA).
A staple of the ESA's Science Doctrine is the Cosmic Vision Programme, a series of space science missions chosen by ESA to launch through competitions, similar to NASA's Discovery and New Frontiers programmes. It follows the Horizon 2000 and Horizon 2000+ programmes which launched notable missions such as Huygens (Titan lander), Rosetta (comet orbiter and lander), and Gaia (astrometry telescope). These missions are divided into two categories: "Sun and Solar System", space probes studying the Solar System (eg. Solar Orbiter studying the Sun and JUICE currently on its way to Jupiter) and "Astrophysics", space telescopes contributing to interstellar astronomy (eg. CHEOPS characterising exoplanets and Euclid focused on dark matter and dark energy).
A similarly operated programme focused on Earth observation, known as the FutureEO Programme (former Living Planet Programme), has launched various "Earth Explorer" satellites, which serve many aspects of Geoscience, often related to climate change. These include eg. GOCE and Swarm studying Earth's gravitational and magnetic fields, CryoSat-2 studying Earth's polar ice caps, and EarthCARE characterising clouds and aerosols in the atmosphere. The Earth Explorer missions will be complemented by a series of smaller "Scout" satellites.
A number of Solar System, Astrophysics, and Earth observation missions by ESA have operated outside of a canonical programme, such as Giotto , Ulysses , Mars Express , Hipparcos , or Envisat . ESA also takes part in human spaceflight missions of other space agencies and commercial partners, eg. by providing European astronauts and major hardware components to the Space Shuttle, Mir , ISS, and Artemis programmes and supporting the Gaganyyan programme. ESA works with European space industry on development of launch vehicles and reentry systems like the Ariane and Vega rockets and the Space Rider spaceplane. Together with other European institutions, ESA develops and operates various satellite constellations for Earth observation, meteorology, communication, and navigation, eg. Meteosat , Sentinel , Galileo , or EDRS. ESA's portfolio also includes public-private partnerships with European satellite operators such as Eutelsat and Inmarsat.