High precision refraction measurements by solar imaging during occultation: results from SOFIE.
A new method for measuring atmospheric refraction angles is presented, with in-orbit measurements demonstrating a precision of +/-0.02 arcsec (+/-0.1 microrad). Key advantages of the method are the following: (1) Simultaneous observation of two celestial points during occultation (i.e., top and bottom edges of the solar image) eliminates error from instrument attitude uncertainty. (2) The refraction angle is primarily a normalized difference measurement, causing only scale error, not absolute error. (3) A large number of detector pixels are used in the edge location by fitting to a known edge shape. The resulting refraction angle measurements allow temperature sounding up to the lower mesosphere.
Gordley
Larry
L
GATS, Incorporated, 11864 Canon Boulevard, Suite 101, Newport News, Virginia 23606, USA. l.l.gordley@gats-inc.com
Burton
John
J
Marshall
Benjamin T
BT
McHugh
Martin
M
Deaver
Lance
L
Nelsen
Joel
J
Russell
James M
JM
Bailey
Scott
S