Volume 15, Number 3, September 1999
By Ramona Kessel
Jesse Leaman and his attendant, Christina Lugo, both of East Stroudsburg University in Pennsylvania, were at the SSDOO for the summer of 1999. Jesse worked with mentor Ramona Kessel on a Sun-Earth connections research project. The project involved many things, not the least of which was learning several new computer systems. Jesse uses voice activation to operate computers, and the software had to be 'taught' new environments and procedures. Jesse also took advantage of the vast data stores at the NSSDC and on CDAWeb to carry out the research.
First of all, he learned to identify crossings of Earth's outer magnetic boundary or bow shock from in-situ satellite measurements. He used the International Solar-Terrestrial Physics (ISTP) program satellites, Geotail and Wind, and also IMP-8. Then he used a least-squares fit of the data on either side of the bow shock to a set of conservation equations across the boundary to determine the normal direction to the surface. In general this surface follows a model surface that is an empirical fit of many satellite crossings since the 1960s. However, at times of transient solar wind features the surface can deviate substantially from the model. Jesse and his mentor were studying the interaction of high speed solar wind streams with the bow shock. These occur most dramatically during the declining phase of the solar cycle. Jesse analyzed several of the high speed stream interactions of which there are multiple (up to 30) crossings of the bow shock by the satellite making the measurements. He also examined times in between the high speed streams for comparison. The surface normals he determined are the basis of the research and will be used in several presentations and papers in the next year by both Jesse and his mentor. In fact, Jesse won the Rashaan Jackson award for best student presentation for his final summer presentation.
One interesting story about the summer involves Jesse's expectations. When Jesse first started as a student, he solved a few of the least squares problems and then asked, "What's the final answer?" His mentor, Ramona Kessel, explained that science answers take time, a lot of hard analysis of data, and persistent questioning. Jesse took that on board and continued to work hard and look for answers. In Jesse's final presentation, he said he was naive when he started but now knew much more about how science is done.
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