2015•Scholarly Commons (Embry–Riddle Aeronautical University)Requires access
Geocoronal Balmer-Alpha Emission Observed by the Wisconsin H-Alpha Mapper During the Southern Sky Survey
E. J. Mierkiewicz, L. M. Haffner, S. M. Nossal, M. L. Wilson, C. Freer, B. Babler, D. D. Gardner, F. L. Roesler
Open publisher page 0 citations
Abstract
After a successful eleven-year run at Kitt Peak Observatory (AZ), the Wisconsin H-Alpha Mapper (WHAM) was moved to Cerro Tololo (Chile) in 2009 to complete the southern portion of the Galactic Balmer-alpha survey. Although WHAM is primarily used for making observations of the interstellar medium, the terrestrial emission present in each of WHAMs astronomical spectra offers a rich resource for studying the Earths atmosphere. Here we present an overview of the terrestrial Balmer-alpha emission collected during WHAMs first five years of operation under southern skies. Seasonal trends and comparisons with northern hemisphere observations will be discussed. WHAM can detect Balmer-alpha emission as faint as 0.05R in a 30s exposure, covering a 200 km/s (4.4 Angstrom) spectral region with 12 km/s spectral resolution from a 1 degree beam on the sky. With this sensitivity, hundreds of spectra can be collected in a single clear night. Although not capable of fully resolving the geocoronal Balmer-alpha line profile itself, WHAMs sensitivity makes it an exceptional instrument for geocoronal Balmer-alpha intensity observations.