Three-dimensional infrared models of the interplanetary dust distribution

Abstract

We have calculated the brightness of zodiacal emission by using the three dimensional optical models of zodiacal cloud. By comparing the calculated brightness distribution with the IRAS observations, we found that the cosine model is the best out of the three for describing the helioecliptic latitude dependence of dust distribution. We also found best parameters for the heliocentric variations of the dust temperature and volumetric absorption cross-section. Inclination and ascending node of the symmetry plane were deduced from annual variations of i) the peak offset latitude and ii) the pole brightness difference. Longitudes of the ascending node derived from i) and ii) are shown to be significantly different from each other.

Interplanetary dust distribution and temporal variability of Mercury's atmospheric Na

“…The correlation coefficient can be more than 0.6 for –104° < Ω < 57° and i > 1.9°. Our results do not correspond completely with the past results [ Leinert et al , 1980; Kelsall et al , 1998; Kwon and Hong , 1998], mainly because of the difference in the position of the observed IPD. Since the IPD density at Mercury is unknown, we cannot conclude whether the IPD vaporization is the dominant release process.…”

Brightness map of the zodiacal emission from the AKARI IRC All-Sky Survey

“…The inclination is not well fixed in our analysis, but is comparable to Kelsall et al's. Many researchers have estimated the symmetry plane's inclination and longitude of ascending node, but their results are not consistent with each other (cf. Table 1 of Kwon & Hong 1998;and Table 3 of Kelsall et al 1998). We think that the inconsistencies of the values of previous researches and ours are caused by the warping of the IPD cloud's symmetry plane.…”

“…This is evidence for an obliquity that the symmetry plane of the zodiacal dust cloud makes with respect to the ecliptic. This enables us to determine the plane's inclination and longitude of ascending node (see Table 1 of Kwon & Hong 1998, and references therein). Another notable feature of the maps is that near the ecliptic plane the ZE in the trailing direction is brighter than in the leading direction.…”