The Fire and Ice missions will for the first time explore two extreme regions of our solar system. The scientific goal of the solar probe is to investigate the origin of both the solar corona and the solar wind. The solar wind outflowing from the corona creates the heliosphere and influences the entire solar system, including the Earth. The processes of solar coronal heating and the solar wind acceleration have defied explanation by remote sensing observations, but in-situ measurement of the plasma characteristics at small distances from the Sun should identify the responsible physical mechanisms. Close imaging of the corona and disk at high latitude angles should untangle the projection effects that plague us here in the ecliptic when we try to understand the solar corona.
Perihelion is planned to be over the west limb.
The currently preferred option for the Fire mission is two spacecraft, one Russian and one American, launched by a single Russian Proton with a U.S. Star 48 final stage. After launch the two spacecraft separate and independently use a Jupiter gravity assist to place them on their trajectories to perihelion at, respectively, four solar radii for the U.S. spacecraft and ten solar radii for the Russian spacecraft. Each country is developing a backup plan to pursue the solar probe objectives alone if the other side is unable to carry out its mission. This has been the 2649th access to this page since April 20, 1995.