Dust coma structure of comet Halley from SP-1 detector measurements
Autor: | Stanislav Klimov, M. A. Balikchin, S. Savin, V. D. Shapiro, V. N. Smirnov, L. S. Gorn, O. L. Vaisberg, V. I. Shevchenko, M. V. Iovlev |
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Rok vydání: | 1986 |
Předmět: | |
Zdroj: | Nature. 321:274-276 |
ISSN: | 1476-4687 0028-0836 |
DOI: | 10.1038/321274a0 |
Popis: | The SP-1 detectors aboard the Vega 1 and Vega 2 spacecraft measured the spectral and spatial distributions of dust grains, with the aim of investigating the dust release process and other properties of the comet nucleus1–3. The dust particle mass spectra do not exhibit the expected low-mass cutoff4 at 10−14 g; instead, they continue to rise to ∼10−16 g. The apex of the dust paraboloid resulting from scattering of sunlight is estimated to lie at a distance of 40–45×103 km from the nucleus, although there is a small number density of particles well beyond this boundary. Particles of mass 10−12–10−14 g are relatively depleted at large distances from the nucleus, due to stronger light scattering by these particles. Strong inhomogeneity of the dust number density suggests the existence of a sunward-pointing cone of enhanced dust emission, of width 70–80°. The spatial dispersion of a narrow dust jet has been used to estimate the sense and period of rotation of the nucleus and the approximate azimuthal location of the jet source, as well as the mass-dependent velocity dispersion of the dust particles. |
Databáze: | OpenAIRE |
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