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A(B) and A(V) are the total extinction at the B and V filter bands. Another measure used in the literature is the absolute extinction A(λ)/A(V) at wavelength λ, comparing the total extinction at that wavelength to that at the V band. R(V) is known to be correlated with the average size of the dust grains causing the extinction.
In Saturn's magnetosphere the active moon Enceladus at 4 (= 6.0 × 10 4 km is Saturn's radius) is a source of oxygen and water ions at a density of 10 9 m −3 and an energy 5 eV. Dust particles are charged to a surface potential of -1 and -2 V. Outside 4 the ion energy increases to 100 eV and the resulting surface potential rises to +5 V. [166 ...
Cosmic dust – also called extraterrestrial dust, space dust, or star dust – is dust that occurs in outer space or has fallen onto Earth. [ 1 ] [ 2 ] Most cosmic dust particles measure between a few molecules and 0.1 mm (100 μm ), such as micrometeoroids (<30 μm) and meteoroids (>30 μm). [ 3 ]
The Zone of Avoidance (ZOA, ZoA), or Zone of Galactic Obscuration (ZGO), [1] [2] is the area of the sky that is obscured by the Milky Way. [ 3 ] The Zone of Avoidance was originally called the Zone of Few Nebulae in an 1878 paper by English astronomer Richard Proctor that referred to the distribution of " nebulae " in John Herschel 's General ...
The vast majority of the electromagnetic radiation from the central stars is absorbed by surrounding dust, then emitted as mid-and far infrared appropriate to the temperature of the dust. This allows almost the entire energy output of the system to be observed at wavelengths that are not strongly affected by interstellar extinction, leading to ...
The thin disk contributes about 85% of the stars in the Galactic plane [3] and 95% of the total disk stars. [2] It can be set apart from the thick disk of a galaxy since the latter is composed of older population stars created at an earlier stage of the galaxy formation and thus has fewer heavy elements. Stars in the thin disk, on the other ...
A comparison of this value with the apparent magnitude allows the approximate distance to be determined, after correcting for interstellar extinction of the luminosity because of gas and dust. In a gravitationally-bound star cluster such as the Hyades, the stars formed at approximately the same age and lie at the same distance. This allows ...
Circumstellar dust is cosmic dust around a star. It can be in the form of a spherical shell or a disc , e.g. an accretion disk . Circumstellar dust can be responsible for significant extinction and is usually the source of an infrared excess for stars that have it.