The Solar Wind Electrons Alphas and Protons (SWEAP) investigation is the set of instruments on the Parker Solar Probe (PSP) spacecraft that will directly measure the properties of the plasma in the solar atmosphere. SWEAP includes two types of instruments: the Solar Probe Cup (SPC) and Solar Probe Analyzers (SPAN). SWEAP has a total of four sensors and is designed to take measurements of the solar wind including electrons, ions of hydrogen (protons), and helium.
The SWEAP Investigation is lead by Dr. Justin C. Kasper of University of Michigan and the Smithsonian Astrophysical Observatory. Institutions participating in SWEAP include the University of California, Berkeley Space Sciences Laboratory, the University of Michigan, the NASA Marshall Space Flight Center, the University of Alabama Huntsville, NASA Goddard Space Flight Center, the University of Iowa, Los Alamos National Laboratory, University of New Hampshire, Draper Laboratory, and the Massachusetts Institute of Technology.