Archives

Part I of this report covered dust storm activity and variations in the albedo markings, along with the remarkable terminator projections seen at high southern latitudes during 2012 March–April. Part II discusses white cloud activity. The appearances of the Equatorial Cloud Band, the Syrtis Blue Cloud and the various orographic clouds were all seasonally normal, while the seasonal commencement of the N. polar cyclonic white clouds were recorded from Ls= 116° onwards; they exhibited obvious signs of vorticity only from Ls= 129°. The N. polar cap retreat was in close accord with the average, but there was a small systematic difference from 2010 when the seasonal separation of Olympia had been slightly delayed: in 2012 the recession of the cap after Ls~ 35° was a little faster. The onset of the N. polar hood was timed at Ls= 151°. The seasonal brightening of Hellas, due to ground frost formation, was well observed in 2012 March–April.

This report describes and analyses observations of the brighter or more interesting comets discovered or at perihelion during 2015, concentrating on those visually observed. Magnitude parameters are given for all comets with observations. Any evolution in the magnitude parameters of those periodic comets with multiple returns is discussed. Additional information on the comets discussed here, and on other comets seen or at perihelion during the year, may be found on the Comet Section’s visual observations web pages.

In this paper we examine the western branch of the Apennine Bench Formation using LROC WAC and NAC images, Clementine multispectral data, the Chandrayaan-1 Moon Mineralogy Mapper (M3), Selene images, the LROC WAC-based GLD100 digital terrain model and terrestrially-obtained CCD images. The study discusses several volcanic features, which are identified as lunar domes and small lunar cones with associated pyroclastic deposits; a possible relationship between them is investigated. We assess the regional geology and provide insight into the distribution and stratigraphy of the volcanic activity which has occurred in the region. Based on the boundaries of the Apennine Bench Formation we argue the presence of a possible megadome extending for 120km and with an average slope angle ξ of 0.5°. Finally, based on CCD telescopic images and the GLD100 dataset, we describe the morphometric properties of four volcanic constructs including their classification.

This paper describes an easy-to-use online form and database for the submission of white light and hydrogen alpha observations to the BAA Solar Section. The graphical output enables an observer to track variations in solar activity over long periods of time, based on their own observations – an advantage over the previous Microsoft Excel-based approach.