Genesis Solar Wind Samples
The Genesis mission, launched in August 2001, collected solar wind at Earth-Sun L1 location for 28 months, and returned to Earth September 2004 with collectors (very pure materials with highly polished surfaces) into which solar wind atoms were implanted, typically 40 to 100 nm below the surface. These samples can be analyzed by sophisticated laboratory instruments in order to precisely determine the composition of the Sun. Since the Sun contains >99% of the mass in the solar system, knowing its elemental and isotopic composition provides a good estimate of the composition of the solar nebula at the time when the planets were forming.
Even though the Genesis capsule crashed upon Earth return, the Genesis samples were recovered (see Salvaging Genesis Sample Science), and the Genesis’ solar data is contributing to new insights in tracing the chemical evolution of diverse planetary samples (including samples from the Moon, asteroids, comets, and Mars), most of which came from a common starting material, the solar nebula. To date, more than 400 Genesis samples have been allocated to the science community.
The Genesis mission included three separate collections: high speed solar wind, coronal mass ejection solar wind and interstream low speed solar wind. Information from these different solar regimes is adding to the understanding of solar physics (figure 1).
A catalog of the collector fragments is available here. The catalog contains images, the material, the dimensions and area, the solar wind regime, and a qualitative assessment of surface condition. Cataloging is an ongoing process with more than 1850 samples characterized.
Figure 1. Genesis mission collected separately three regimes of the solar wind: Interstream slow solar wind, coronal hole high speed solar wind, and coronal mass ejection solar wind.
Image courtesy of Roger Wiens, Los Alamos National Laboratory
More about the Genesis Mission, including the science goals and results, are located at the Genesis Mission page at http://genesismission.jpl.nasa.gov.