Recent observations of Cepheids using infrared interferometry and Spitzer photometry have detected the presence of circumstellar envelopes (CSE) of dust and it has been hypothesized that the CSE’s are due to dust forming in a Cepheid wind. Here we use a modified Castor, Abbott & Klein formalism to produce a Cepheid wind, and this is used to estimate the contribution of mass loss to the Cepheid ...

Only a few solar-type main-sequence stars are known to be orbited by warm dust particles; the most extreme is the G0 field star BD +20 307 that emits 4% of its energy at mid-infrared wavelengths. We report the identification of a similarly dusty star HD 23514, an F6-type member of the Pleiades. A strong mid-IR silicate emission feature indicates the presence of small warm dust particles, but wi...

The intrinsic and practical predictability of the Martian atmosphere is determined by use of a comprehensive numerical circulation model and ensemble forecasting techniques. Initial conditions were derived for various seasons of the Martian climate from newly available assimilations of global observations of temperature and dust optical depth in the Martian atmosphere, obtained by the Thermal E...

A farmer and his two sons during a dust storm in Cimarron County, Oklahoma, 1936, Photo: Arthur Rothstein The Dust Bowl, or the Dirty Thirties, was a period of severe dust storms causing major ecological and agricultural damage to American and Canadian prairie lands in the 1930s, particularly in 1934 and 1936. The phenomenon was caused by severe drought coupled with decades of extensive farming...

The quality of pressure distribution over the atmosphere of the sea level and geopotential altitude at different atmosphere layers affect on many climate and meteorology phenomena of the earth surface. One of the important meteorology phenomenon is the occurrence of frost phenomenon especially late spring frost. In this surrey, occurring late spring frost days and minimum temperature during the...

After having presented a theoretical outline of the light echo phenomenon and results of simple numerical simulations we study the available images of the light echo in V838 Mon obtained with HST. From an analysis of the observed expansion of the light echo we conclude that the distance to V838 Mon is greater then ∼5 kpc. We also investigate the structure of the dust distribution in the vicinit...

The cometary atmosphere is a unique phenomenon in the solar system. Owing to its negligible gravity, comets produce highly variable extensive dusty atmospheres with a size much larger than the characteristic size of the cometary nucleus. As the comet approaches the sun, the water vapor with some fraction of other gases sublimates, generating a cloud of gas and dust from the surface of cometary ...

Electromagnetic wave propagation in arid and semi-arid regions is influenced by sand and dust storms. Meagre information has hitherto been reported as to the effect of storms on telecommunication systems operating in such regions. This paper presents a survey of current understanding of the wave propagation during storms. In this first part of the review—Part I, detailed parametric assessment o...

Some time ago the author had occasion to prepare a quantity of phenyl thio carbamide, and while placing it in a bottle the dust flew around in the air. Another occupant of the laboratory, Dr. C. R. Noller, complained of the bitter taste of the dust, but the author, who was much closer, observed no taste and so stated. He even tasted some of the crystals and assured Dr. Noller they were tasteles...