October 23, 2013
American Center for Physics
College Park, MD
Date: Wednesday, 23 October, 2013 (NEW DATE!!)
Speaker: Keith Strong
Topic: The Solar Cycle Conundrum
Time and Location: 1:00 pm, with Q&A to follow; in a 1st floor conference room at the American Center for Physics (www.acp.org), 1 Physics Ellipse, College Park, MD — off River Rd., between Kenilworth Ave. and Paint Branch Parkway.
Abstract: We have known for 170 years that sunspots come and go on a roughly 11-year timescale. Despite many efforts to develop empirical and physical models of the solar cycle, we have failed to find a method of predicting the timing or amplitude of the upcoming solar cycle with any degree of confidence. While this was once considered an interesting intellectual exercise to test how well we understood the inner workings of the Sun, it now has become an important economic factor as our dependence on space technology increases. The vulnerability of our space assets to space weather effects increases with the solar activity levels that are driven by the solar cycle.
The Sun is a magnetic variable star, so we will look at the basic characteristics of the solar dynamo that have to be reproduced by any solar cycle model. We will then briefly discuss some of the techniques used to predict solar activity and see how well they have done so far in predicting the current solar cycle. Extended observations of the Sun’s magnetic field from SOHO and various ground-based observatories, in conjunction with coronal imaging, has led us to find some new aspects of the solar cycle that have shown some promise for predicting certain aspects of the solar cycle. One of the main problems we face in understanding the solar cycle is that the Sun is under sampled. We will discuss a potential new solar mission that would provide new insights into the solar cycle.
Biography: Dr Strong attained his undergraduate degree in Astronomy at University College, London (UCL). He completed his Ph.D. on X-ray Spectroscopy of the Sun at the Mullard Space Science Laboratory in 1979. After a brief attempt to become Britain’s first astronaut, he joined Lockheed Solar Astrophysics Laboratory. He was appointed Principle Investigator of the X-ray Polychromator Experiment on NASA’s Solar Maximum Mission satellite in 1984. He worked in Japan on the Yohkoh Soft X-ray Telescope for three years. In 1995, he was selected as manager of the Solar & Astrophysics Laboratory, where he helped them win instrument contracts on GOES-N, TRACE, STEREO, SDO, Triana, JWST, and GOES-R. In 2000, he chaired NASA’s Sun-Earth Connection Roadmap that introduced the “Living With a Star Program”. He retired from Lockheed Martin as acting director for space sciences in 2007 and has an emeritus position at NASA’s GSFC through the University of Maryland.