Solar probe

Solar probe can refer to:

Solar Probe Plus

Solar Probe Plus or Solar Probe+, previously NASA Solar Probe, is a planned robotic spacecraft to probe the outer corona of the Sun. It will approach to within 8.5 solar radii (0.034 astronomical units or 5.9 million kilometers or 3.67 million miles, roughly 1/8 of the perihelion of Mercury) to the 'surface' (photosphere) of the Sun. The project was announced as a new mission start in the fiscal 2009 budget year. On May 1, 2008 Johns Hopkins University Applied Physics Laboratory announced it will design and build the spacecraft, on a schedule to launch it in 2015. The launch date has since been pushed back to 2018, with the Delta IV Heavy as the launch vehicle.

Trajectory and mission

Early conceptual designs for the Solar Probe mission used a gravity assist maneuver at Jupiter to cancel the orbital angular momentum of the probe launched from Earth, in order to drop onto a trajectory close to the Sun. The Solar Probe Plus mission design simplifies this trajectory by using repeated gravity assists at Venus, to incrementally decrease the orbital perihelion to achieve multiple passes to approximately 8.5 solar radii, or about 6,000,000 km (3,700,000 mi).