Solar Orbiter is an ESA-led mission due for launch in 2017. It will travel closer to the Sun than any previous mission, going to within approximately a quarter of the Earth’s distance from the Sun.
- Solar Orbiter is part of ESA's Cosmic Vision Programme
- The mission is to travel closer to the Sun than any previous Sun-watching mission
- Officially adopted by ESA on 4 October 2011 to proceed to Implementation Phase
- The launch of the Solar Orbiter mission is planned for 2017
- The nominal mission lifetime is 6 years
The mission orbit will take the spacecraft on an ellipse around the Sun that will process taking it up to the Sun’s higher latitudes to study the polar regions for the first time and to enable the solar features to be kept in view and tracked for several weeks. The spacecraft journey to reach a solar inclination of over 30° will take over three years and will use several Venus and Earth flybys.
The suite of instruments on board the spacecraft will undertake remote sensing observations of features in the direction they are pointed and in situ measurements as the solar wind bombards the spacecraft. This combination of remote and in situ instruments will enable in depth studies of the connections between the Sun and space. This unique mission could provide major breakthroughs in our understanding of how the inner solar system works and is driven by the solar activity.
The three-axis stabilised design of the spacecraft is being developed to withstand the scorching heat from the Sun that will hit one side and the cold of space on the opposite side always remaining in shadow. The spacecraft is based on the design used for the BepiColombo mission, which also travels relatively close to the Sun, and the solar arrays are being engineered to provide the critical power supply without overheating.
Solar Orbiter is managed and financed mainly by ESA with strong international collaboration with NASA as part of the International Living with a Star initiative.
Solar Orbiter merged as one of two Medium sized missions selected for the M1/M2 missions, part of the Cosmic Vision programme.
For further information please see the Solar Orbiter pages on the ESA website.
Solar Orbiter will be the first spacecraft to provide close-up views of the Sun’s polar regions.
The mission orbit is designed to be synchronous with the Sun’s rotation providing long duration observations for the first time. This will enable the mission to observe the build up of events such as solar storms.
Solar Orbiter will carry a comprehensive suite of instruments studying remote features on the Sun and in situ measurement at the spacecraft providing a close link between the origin of solar features such as solar eruptions and their emergence into space.
The Solar Orbiter spacecraft is based on the Mars Express/Venus Express design reusing the technology developed for the BepiColombo spacecraft. Additional heat protection will be added to enable it to operate in extreme thermal environments. The instruments will be provided with cut-outs and doors in the heat shield with the overall dimensions of 2.5 x 3.0 x 2.5 m. The instruments have been selected jointly by ESA and NASA as part of the collaboration to provide the in situ and remote observations.
In situ instruments
- SWA (Solar Wind Analyser) will use three components to measure the different elements of the solar wind and characterise their behaviour under different solar conditions. MSSL of the University of College London will lead the development of this instrument suite.
- EPD (Energetic Particle Detector)
- MAG (Magnetometer) will have two sensors located on a deployable boom in the shadow of the spacecraft, i.e. away from the Sun, enabling it to sample the magnetic field in situ and providing important diagnostic information. Imperial College London will lead the development of this instrument.
- RPW (Radio and Plasma Waves)
- PHI (Polarimetric and Helioseismic Imager)
- EUI (Extreme Ultraviolet Imager) will be a suite of imaging telescopes that will provide images of the hot and cold layers of the solar atmosphere and of the solar corona showing the dynamics in fine detail and providing the link between the solar surface and outer corona. MSSL of the University College London is a Co-Investigator for this instrument.
- SPICE (Spectral Imaging of the Coronal Environment) is a telescope with a grating spectrograph and two active pixel sensor detectors that will provide images of the solar disk and corona. SPICE will be able to study features both on the surface and out in the corona and to look at the connection between them. Rutherford Appleton Laboratory is Principal Investigator for this instrument.
- STIX (X-ray Spectrometer Telescope)
- METIS/COR (Coronagraph)
- SolOHI (Heliospheric imager)
The UK is playing a major role in the development of Solar Orbiter with UK teams from University College London, Imperial College London and Rutherford Appleton Laboratory involved in four out of the ten instruments and holding the industrial lead. Principle Investigators from UCL’s Mullard Space Science Laboratory and Imperial College London lead the development of the Solar Wind Analyser (SWA) and Magnetometer (MAG) respectively.
The UK Space Agency is funding the UK involvement.
UK industry will play a key role in mission development. EADS Astrium Limited, based in Stevenage, is leading the industrial study for the spacecraft development. Further industrial involvement will be confirmed following mission selection.