Solar Probe Plus

The U.S. Solar Probe Plus mission will begin its voyage to the Sun in 2018, aiming to become the first spacecraft to venture into our star’s outer atmosphere. It is scheduled to arrive in 2024.

Once lofted into space by a Delta IV Heavy launcher, Solar Probe Plus will need 7 gravity assists from Venus to reach the Sun’s corona. These successive gravitational boosts will make it the fastest spacecraft of all time. It will also be the first to study the solar wind in situ with its 4 suites of instruments. The solar wind is the stream of ions and electrons that our star ejects at high speed into interplanetary space. Solar Probe Plus will pass several times within less than 7 million km of the Sun’s surface, where it will be exposed to temperatures of 1,400°C.

French research laboratories—the LPC2E environmental and space physics and chemistry laboratory, the LESIA space and astrophysics instrumentation research laboratory, the IRAP astrophysics and planetology research institute, the LPP plasma physics laboratory and the LAM astrophysics laboratory in Marseille—are contributing to Solar Probe Plus’s instruments, with support from CNES. The PROMES processes, materials and solar energy laboratory, which operates the solar furnace in Odeillo in the French Pyrenees, is also working on the mission, studying the behaviour at high temperatures of the parts of the science instruments that will not be protected by the probe’s solar shield.

The Solar Probe Plus mission is being coordinated with the European Solar Orbiter mission as part of the joint HELEX programme (Heliophysics Explorers).