MSX Observations of the Zodiacal Cloud

S. Jayaraman, R. G. Walker (VRI), S. D. Price (AFRL)

Data obtained from the SPIRIT III radiometer, aboard the Midcourse Space Experiment (MSX) satellite, has provided us with new and unique observations of the Zodiacal cloud in four infrared wavebands between 6.8 to 25.1 microns. Zodiacal measurements were obtained on a total of 69 observations over the 10 month cryogen phase of the mission. The observations consist of long scans ( tex2html_wrap_inline11 ) at (nearly) constant ecliptic longitude; about two-thirds of these scans include the north ecliptic pole. In aggregate, the scans cover solar elongations between tex2html_wrap_inline13 and tex2html_wrap_inline15 , far larger than the IRAS plus COBE limits of tex2html_wrap_inline17 to tex2html_wrap_inline19 . Thus, the uniqueness of this data set enables us, for the first time, to systematically probe the dust distribution in the zodiacal cloud, as well as the variation in the structure of the cloud, from the sun to the asteroid belt using data from a single experiment. We present samples of the data from the as ecliptic pole-to-pole scans taken at the smaller elongations.