Introduction: Since the discovery of ice in cold, permanently shadowed polar craters on Mercury[1], debate has reopened over the presence of ice in similar environments on the Moon. Though the Moon has similar shadowed craters currently, this has not always been the case. Here we examine a 4.5 billion year history of insolation in the lunar polar environment and the resulting surface and subsur...

Clouds have been observed recently on Titan, through the thick haze, using near-infrared spectroscopy and images near the south pole and in temperate regions near 40 degrees S. Recent telescope and Cassini orbiter observations are now providing an insight into cloud climatology. To study clouds, we have developed a general circulation model of Titan that includes cloud microphysics. We identify...

We present linear polarization characteristics of pulsar radiation as predicted by two models of high-energy radiation from extended regions in the outer magnetosphere: the recently proposed two-pole caustic 1 Two-pole caustic model vs outer gap model The two-pole caustic model differs from the outer gap model in that its emission region extends below the null charge surface toward the polar ca...

Information necessary for the formation of pole cells, precursors of the germ line, is provided maternally and localized to the posterior pole of the Drosophila egg. The maternal origin and posterior localization of polar granules suggest that they may be associated with pole cell determinants. We have generated an antibody (Mab46F11) against polar granules. In oocytes and early embryos, the Ma...

Titan's middle atmosphere is characterized by cyclostrophic winds and strong seasonal modulation. Cassini CIRS observations, obtained in northern winter, indicate that the stratosphere near 1mbar is warmest at low latitudes, with the South Pole a few degrees colder and the North Pole approximately 20K colder. Associated with the cold northern temperatures are strong circumpolar winds with speed...

Light microscope descriptions of meiosis I in males of the fungus gnat Sciara coprophila suggested the presence of a monopolar spindle in which maternal and limited chromosomes move poleward while paternal chromosomes "back away" from the pole. The ultrastructural analysis reported here, based upon serial sections of cells in different stages of meiosis I, shows that the spindle is indeed monop...

The conservative cascade scheme (CCS) combines a one-dimensional mass-conserving finite-volume method with an efficient semi-Lagrangian scheme over the sphere. Major limitations of this scheme are a breakdown in the polar region due to the coordinate singularity and a restriction to polar meridional Courant number Cu # 1. The proposed scheme is an extension of the CCS over the sphere for Cu . 1...

Solutions of partial differential equations with coordinate singularities often have special behavior near the singularities, which forces them to be smooth. Special treatment for these coordinate singularities is necessary in spectral approximations in order to avoid degradation of accuracy and efficiency. It has been observed numerically in the past that, for a scheme to attain high accuracy,...

In Drosophila embryos, germ cell formation is induced by specialized cytoplasm at the posterior of the egg, the pole plasm. Pole plasm contains polar granules, organelles in which maternally produced molecules required for germ cell formation are assembled. An untranslatable RNA, called Polar granule component (Pgc), was identified and found to be localized in polar granules. Most pole cells in...

Polar mesospheric clouds (PMCs) were observed above the geographic South Pole by an Fe Boltzmann temperature lidar from 11 Dec 99 to 24 Feb 00. During this 76-day period 297 h of observations were made on 33 different days and PMCs were detected 66.5% of the time. The mean PMC peak backscatter ratio, peak volume backscatter coefficient, total backscatter coefficient, layer centroid altitude, an...