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.Due
to budget cuts ,now it will cost more because they have to store the
space probe in a clean room which cost about 1million for every few
months or so.. PS You can't just leave sitting around the office LOL!
This art photo show how the solar cell will be during the close approach
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 multiple 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).
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 penumbra of the shield. 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 of 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.
As the probe passes around the Sun, it will achieve a velocity of up
to 200 km/s (120 mi/s) at that time making it the fastest manmade object
ever, almost three times faster than the current record holder, Helios
II.
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