We present time-series spectropolarimetric observations of sunspots in the Ca II infrared triplet lines, which show a periodic occurrence of anomalous, asymmetric, circular polarization profiles in the umbral chromosphere. The profiles may be caused by the periodic development of an unresolved atmospheric component in a downward flowing magnetized

We present time-series spectropolarimetric observations of sunspots in the Ca II infrared triplet lines, which show a periodic occurrence of anomalous, asymmetric, circular polarization profiles in the umbral chromosphere. The profiles may be caused by the periodic development of an unresolved atmospheric component in a downward flowing magnetized

Continuum subtracted dereddened images in several emission lines reveal the existence of an extended bipolar shell around η Carinae. It is best seen in the light of [ion{O}{3}]5007. The geometrical disposition and mass of the shell-between 5 and 7 Modot-suggest that it was produced by mass outflows from this star. The approximate size and dynamic

We present the results of a 2-D, two fluid (ions and neutrals) simulation of the ambipolar filamentation process, in which a magnetized, weakly ionized plasma is stirred by turbulence in the ambipolar frequency range. The higher turbulent velocity of the neutrals in the most ionized regions gives rise to a non-linear force driving them out of these

Ring diagram analysis, a technique of local helioseismology, has been applied to 120 regions of 15deg×15deg over the solar surface in order to study the mass motions in the upper layers of the convection zone. The horizontal flows from ~0.95 Rsolar up to the surface have been investigated in a region spanning 360deg in longitude and about 75deg in

Available from the Minor Planet Center.