Composition of the Solar Wind
Abstract
The motivation for systematic observations of the solar wind composition is twofold: (1) It may be used to deduce the composition of the protosolar nebula from which the entire solar system was made 4.6 gigayears ago, thus representing a sample of the galactic chemical evolution at that time and location. (2) It is a tracer of conditions and processes in the solar atmosphere where the solar wind is accelerated, thus providing information about the structure of the corona. With the launch of a new type of composition sensor on the Ulysses mission in 1990 we have now a database of ten elements in more than 30 charge states during more than a complete solar activity cycle. Together with Ulysses' unique, high-inclination orbit that database reveals much about the three-dimensional structure of not just the solar atmosphere, but also of the heliosphere as a whole. We will review the Ulysses observations of solar wind composition both in its quasi-stationary states, steady fast streams and variable slow wind, as well as in its transient states such as coronal mass ejections, and their significance for the structure of the heliosphere.
- Publication:
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37th COSPAR Scientific Assembly
- Pub Date:
- 2008
- Bibcode:
- 2008cosp...37.3366V