Abstract Thermal emission from the interplanetary dust cloud has been confirmed by IRAS to be the most prominent component of the sky brightness in the 10–25 μm range. It is indeed a severe foreground for astronomical observations. It is also a major source of information on the local properties of the dust grains. Unlike the solar scattered light (zodiacal light), the thermal emission of the grains is isotropic; even more progress can therefore be expected from the inversion of IRAS integrated brightnesses. The pre-IRAS understanding of the interplanetary dust cloud is reviewed. Recent results obtained through inversion methods are presented. In the ecliptic near 1 AU, the heliocentric gradient of temperature is about −0.33, i.e. conflicts with a greybody assumption, while the gradient of albedo is about −0.7, i.e. conflicts with a homogeneous cloud assumption. Out of the ecliptic, the dust distribution is still open to dispute. It is however neither smooth (dust bands and trails, warped symmetry surface), nor homogeneous (location dependence of local polarization or albedo). Such results imply that the mixing ratios of the various interplanetary dust sources (comets, asteroids, β meteoroids) strongly depend upon location in the cloud.
IRAS observations and local properties of interplanetary dust
Advances in Space Research ; 10 , 3-4 ; 163-170
1989-01-01
8 pages
Article (Journal)
Electronic Resource
English
IRAS observations of cometary dust
Elsevier | 1984
|IRAS observations of cometary dust
NTRS | 1984
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