PLATO (PLAnetary Transits and Oscillations of stars) is a medium-class mission (M3) officially selected for the European Space Agency’s Cosmic Vision 2015-2025 programme on 19 February 2014. It draws on the heritage of its predecessors CoRoT, a French mission with European partners, the U.S. Kepler and TESS missions, and ESA’s Cheops mission co-funded by the Swiss Space Agency.
Key information
| Mission | Detect and study new star-planet systems, in particular Earth-like planets orbiting in the habitable zone of Sun-like stars |
|---|---|
| Domain | Science |
| Launch date | Scheduled December 2026 |
| Partners | ESA, CNRS, CEA, universities, OHB, Thales Alenia Space, RUAG |
| Where | Large-amplitude libration orbit around L2 Lagrange point |
| Lifetime | Nominal mission: 4 years Possible extension to 6½ years Design lifetime (until expected depletion of fuel): 8 years |
| Status | In development |
Key figures
- 24 + 2: telescopes on PLATO
- 3%: planet diameter measurement precision using the transit method with PLATO
- 10%: planet mass measurement precision using the radial velocity method with ground telescopes
- 10%: uncertainty on age, mass and radius of stars observed by PLATO
- 20,000 stars observed in each of 10 fields viewed by PLATO
Key milestones
- December 2026: Scheduled launch of PLATO
- October 2018: ESA selects OHB, Thales Alenia Space and RUAG to build satellite
- June 2017: Start of development phase
- 20 June 2017: ESA adopts PLATO mission
- 19 February 2014: ESA selects PLATO for its Cosmic Vision 2015-2025 programme
Project in brief
PLATO is setting out to answer three fundamental questions:
- How do planets and planetary systems form?
- Is our solar system unique or are there other planetary systems identical to our own?
- Do these systems harbour potentially habitable planets
To this end, PLATO will detect thousands of exoplanetary systems in our galaxy and determine their mass and orbital properties, as well as those of their stars and the age of their exosystem. The programme is founded on three pillars:
- Detection of exoplanets using the transit method (learn more here, here or here)
- Characterization of their stars by asteroseismology (learn more here)
- Measurement of the radial velocity of the stars of detected exoplanets, using ground telescopes (learn more here or here).
PLATO will continuously survey a vast field of view of the sky in each hemisphere. Each hemisphere will be surveyed for two years, enabling detection of planets that circle their stars in the same time period as the Earth-like planets in our own solar system, and possibly longer (e.g. Mars orbits the Sun in about 22½ months).
PLATO will carry a payload module (PLM) comprising 24 telescopes operating in the visible portion of the spectrum, affording a vast combined field of view covering a total sky area of some 2,232 square degrees, i.e., roughly 5% of the sky. In comparison, a full Moon seen from Earth only covers about 0.2 square degrees of sky. The payload also includes two additional ‘fast’ cameras for fine pointing of the satellite and identification of targets suitable for closer analysis, especially the composition of their potential atmosphere by other space telescopes like JWST or in the future ESA’s dedicated ARIEL mission.
PLATO is scheduled for launch by an Ariane 62 from Kourou in December 2026 to the L2 Lagrange point 1.5 million kilometres from Earth, in the direction away from the Sun.
CNES’s role
28 nations and some 300 institutes are contributing to the PLATO consortium, led by Germany. France is one of the four main contributors with Germany, Italy and the United Kingdom. CNES is overseeing the French contribution and supervising the work of nine laboratories attached to the national scientific research centre CNRS and CEA, the French atomic energy and alternative energies commission.
Contacts
Project Leader for French Contributions to PLATO
André Debus
E-mail: andre.debus at cnes.fr
Exobiology, Exoplanets & Planetary Protection subject matter expert
Christian Mustin
E-mail: christian.mustin at cnes.fr