The Flare Genesis Experiment


The goal of the Flare Genesis Experiment is to make solar observations at the highest practicable resolution in order to improve understanding of the mechanisms involved in many different types of solar activity, particularly flares and solar filament eruptions. Achieving this goal demanded the development of a balloon-borne platform for an 80-cm F/1.5 optical telescope that could maintain 10 arcsec pointing stability. The first flight of the Flare Genesis Experiment took place in January 1996. In the stratosphere, 37 km above Antarctica, for more than 19 days, the Flare Genesis telescope pointed at the Sun with the planned stability. While the primary science objective, to measure the vector magnetic fields using two liquid crystal polarization modulators, was not achieved on this flight, 18,000 continuum images were obtained. They demonstrate that the major engineering challenges for such a flight were overcome. In addition, we developed an image motion compensation system capable of limiting the motion of the Sun’s image on the focal plane to less than the system’s 0.2 arcsec diffraction limit. Other key elements on board included a lithium-niobate Fabry- Perot etalon filter to provide a tunable 0.016-nm bandpass over a wide wavelength range, a 1538 x 1024- pixel CCD camera and 100 GBytes of on-board storage. We will describe the payload design and how the instruments performed. We will discuss how the constraints of long duration Antarctic ballooning guided the final design and impacted the results. Two more flights are planned before the next solar maximum. Such long-duration balloon flights provide a relatively inexpensive means to observe the Sun at the highest resolution and to develop instrumentation and techniques for future space missions.

American Astronomical Society Meeting Abstracts #188