Solar eclipse observations from the ground and air from 0.31 to 5.5 microns

Friday, March 29, 2019

We present spectra and broad-band polarized light data from a suite of instruments deployed during the 21st August 2017 total solar eclipse. Our goals were to survey solar spectra at thermal infrared wavelengths during eclipse, and to test new technology for measuring polarized coronal light.

Graph of Spectra of the limb photosphere
Spectra of the limb photosphere during the 21st August 2017 eclipse as obtained from Camp Wyoba, Wyoming.

An infrared coronal imaging spectrometer, flown at 14.3 km altitude above Kentucky, was supported on the ground by observations from Madras, Oregon (elevation 683 m) and Camp Wyoba on Casper Mountain, Wyoming (2402 m). In Wyoming we deployed a new infrared Fourier Transform Spectrometer, three low-dispersion spectrometers loaned to us by Avantes, a novel visible-light camera PolarCam, sensitive to linear polarization, and one of two infrared cameras from FLIR Systems, the other operated at Madras. Circumstances of eclipse demanded that the observations spanned 17:19 to 18:26 UT. We analyze spectra of the limb photosphere, the chromosphere, prominences, and coronal lines from 310nm to 5.5$\mu$m. The PolarCam data are compared with the K-Cor synoptic instrument on Mauna Loa from the same day. We discuss novel results, including a detection of the \ion{He}{1} 1083 nm multiplet in emission during the whole of totality.

Publication Name: ApJ

First HAO Author's Name: Philip Judge