Mid-Infrared Observing Conditions at the South Pole

• Main Authors: Chamberlain Ashley Burton, M. A. Chamberlain, M. C. B. Ashley, M. G. Burton, A. Phillips, J. W. V. Storey
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2000
• Subjects: South Pole; South pole
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.27.3848; http://www.phys.unsw.edu.au/~mgb/Antbib/mismfinal.ps.gz

Measurements of the mid-infrared sky brightness at the South Pole throughout the winter of 1998 show that the sky background is extremely low and stable. For 50% of the time the flux in the 8.78 to 9.09 m window is below 50 Janskys per square arcsecond. Typical background levels in this window during clear conditions are of the order of 20 Janskys per square arcsecond. This is almost an order of magnitude better than any other site on earth. The lower limit to the sky background across most of the N-window appears to be set by the aerosol content of the sky, rather than by residual water vapor. These data were acquired remotely using an automated instrument housed in the AASTO (Automated Astrophysical Site-Testing Observatory). Subject headings: site testing; atmospheric effects -- 3 -- 1. Introduction Astronomical observations in the mid-infrared from the ground are limited by an atmospheric thermal background flux that is orders of magnitude greater than that of the objects studied.