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Ground-Based Photometry of Mars in 2003 and 2005 and Physically Constrained Iterative Estimation

Wednesday, November 2, 2005

Michael Snowden
'Globe-Trotting Astronomer' and
E. Keith Hege
MKS Imaging Technology, LLC

Michael Snowden

Interim report on extensive (10,000) ground-based images obtained of Mars at the National Observatory of Argentina (CASLEO) during the 2003 opposition with similar on-going observations at the Kuiper Telescope in Arizona in 2005. First results reveal surprising clarity in the ultraviolet of Martian atmospheric activity, which has resulted from near-zenith imaging. Photometry of the images have the potential for cloud-opacity calibrations with TES and subsequently for diurnal values that TES cannot see. Current techniques under development for cloud wind vectors may be applicable.

E. Keith Hege

The problem of image estimation in the presence of atmospheric blurring and readout noise can be solved as a forward estimation problem even with unknown PSF. Knowledge of the PSF is useful, as that allows application of the most widely known forward filtering method; the Wiener filter. However, Wiener filtering has another well-known problems. Although it is an optimum filter, it is also a measurement noise amplifier. Other iterative methods, such as Richardson-Lucy and multiple frame blind deconvolution fail to recognize that the simultaneous estimation of the PSF is neither blind, nor is it a decolvolution problem. One need never be blind about the fixed optical properties of the optical system, nor about the noise statistics of the measurements. By providing good physical models of both the fixed optics and the atmospheric and measurement noise, forward models of the measurement PSF can be constructed, and used successfully to estimate data sets from observations for which the atmospheric noise and the measurement noise are random, zero-mean processes. Some results using physically constrained iterative estimation will be shown from data provided by Michael Snowden's 2003 and 2005 Mars opposition observations.

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