The NASA Solar Probe Mission: In Situ Determination of Interplanetary Out-of-the Ecliptic and Near-Solar Dust Environments

Abstract

The NASA Solar Probe mission will be one of the most exciting dust missions ever flown and will lead to a revolutionary advance in our understanding of dust within our solar system. Solar Probe will map the dust environment from the orbit of Jupiter (5 AU), to within 4 solar radii of the sun’s center. The region between 0.3 AU and 4 R_s has never been visited before, so the 10 days that the spacecraft spends during each (of the two) orbit is purely exploratory in nature. Solar Probe will also reach heliographic latitudes as high as ∼ 15° to 28° above (below) the ecliptic on its trajectory inbound (outbound) to (from) the sun. This, in addition to the ESA/NASA Ulysses mission, will help determine the out-of-the-ecliptic dust environment. A post-perihelion burn will reduce the satellite orbital period to 2.5 years about the sun. A possible extended mission would allow data reception for 2 more revolutions, mapping out a complete solar cycle. Because the near-solar dust environment is not well understood (or is controversial at best), and it is very important to have better knowledge of the dust environment to protect Solar Probe from high velocity dust hits, we urgently request the scientific community to obtain further measurements of the nearsolar dust properties. One prime opportunity is the July 1991 solar eclipse.