Comparisons of Novel Imaging and Spectroscopic Infrared Eclipse Observations in 2017

Abstract:

The 2017 total solar eclipse was a valuable opportunity to make unique observations in the Mid-Wave Infrared (3–5 μm) passband at high altitudes to study organized structures in the corona in an under-observed wavelength range. Using two NASA WB-57 research aircraft at 52,000 feet, we observed about 7.5 minutes of totality. We compared our images to measurements taken by the Airborne Infrared Spectrometer (AIR-Spec) on the NSF HIAPER Gulfstream V flying at 47,000 feet and observations from the Solar Ultraviolet Imager (SUVI) on the GOES-16 spacecraft. Directly comparing these data allows us to interpret our broadband images in the context of these new spectral measurements that highlight the physical processes in the corona. Overlaying the AIR-Spec spectra at their four slit positions on our broadband MWIR images reveal the IR spectral lines contributing from a solar prominence and an active region that we focus on. SUVI gives us a calibrated reference against which to compare our two experimental data sets. Comparison of the spectral data from AIR-Spec with high-resolution filter imaging from WB-57 and SUVI provides temperature diagnostics and spatial context not available from existing EUV and visible light observations to probe the physical nature of the structures. This study is a pathfinder for future coordinated observations with upgraded instrumentation to measure key spectral lines, sampling temperatures and ionization states largely inaccessible in other wavelengths, to improve understanding of heating and evolution of coronal structures. This research was possible through by the Boulder Solar REU program’s innovative virtual curriculum, funded by the National Science Foundation, award #1659878.