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 (5.9 million kilometers or 3.67 million miles) 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.This was due to budget matters.
The mission is designed to survive the harsh environment near the Sun,
where the incident solar intensity is approximately 520 times the
intensity at Earth orbit, by the use of a solar shadow-shield. The solar
shield, at the front of the spacecraft, is made of reinforced carbon-carbon composite. The spacecraft systems, and the scientific instruments, are located in the umbra
of the shield, where direct light from the sun is fully blocked. The
primary power for the mission will be by use of a dual system of
photovoltaic arrays. A primary photovoltaic array, used for the portion
of the mission outside 0.25 AU, is retracted behind the shadow shield
during the close approach to the Sun, and a much smaller secondary array
powers the spacecraft through closest approach. This secondary array
uses pumped-fluid cooling to maintain operating temperature.The first time in history where they are going to used water like stuff to cool down the space probe as it get within 3 million miles from the sun.
It would used flyby of Venus to get the orbit closer to the sun. The shield is base on design of the MESSENGER space probe that orbit Mercury,This shield s 4inch thick.They wanted to do this for 50 years but the tect wasn't there let. They are also planing a solar orbiter this is between NASA and the ESA
In September 2010, NASA selected five investigations for Solar Probe Plus:
Solar Wind Electrons Alphas and Protons Investigation,
which will specifically count the most abundant particles in the solar
wind — electrons, protons and helium ions — and measure their
properties. The investigation also is designed to catch some of the
particles in a special cup (known as a Faraday cup) for direct analysis.
Principal Investigator: Justin C. Kasper, Smithsonian Astrophysical Observatory, Cambridge, Mass.
The Wide-field Imager, a telescope that will make
3-D images of the sun's corona, or atmosphere. The experiment actually
will see the solar wind and provide 3-D images of clouds and shocks as
they approach and pass the spacecraft. This investigation complements
instruments on the spacecraft providing direct measurements by imaging
the plasma the other instruments sample. Principal Investigator: Russell Howard, Naval Research Laboratory, Washington
The Fields Experiment, which will make direct
measurements of electric and magnetic fields, radio emissions, and shock
waves that course through the Sun's atmospheric plasma. The experiment
also serves as a giant dust detector, registering voltage signatures
when specks of space dust hit the spacecraft's antenna. Principal Investigator: Stuart Bale, University of California Space Sciences Laboratory, Berkeley, Calif.
The Integrated Science Investigation of the Sun,
which consists of two instruments that will take an inventory of
elements in the Sun's atmosphere using a mass spectrometer to weigh and
sort ions in the vicinity of the spacecraft. Principal Investigator: David McComas, Southwest Research Institute, San Antonio.
Heliospheric Origins with Solar Probe Plus Principal
Investigator Marco Velli, of NASA's Jet Propulsion Laboratory,
Pasadena, Calif., is the mission's observatory scientist, responsible
for serving as a senior scientist on the science working group. He will
provide an independent assessment of scientific performance and act as
a community advocate for the mission.