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Presented here is a report covering observations of Venus during the 2018–’19 eastern and western elongations. Part I concerns observations made by Section members during the eastern elongation, while Part II deals with the western elongation. Images and drawings submitted to the Section are presented for analysis and various aspects of the planet’s appearance during the period considered are commented upon.

A search of published literature reveals 54 western reports of candidate naked-eye sunspot observations made before sunspots were first viewed by telescope in 1610. Most have not had critical scrutiny. Criteria for assessing the reports are presented and each report is reviewed accordingly. Brief extracts from original texts are provided, with translations and full documentation of sources. The review identifies 20 cases that are either misdated or attributable to other phenomena, 15 cases that lack evidence, and six cases that are no more than plausible sunspots. A total of 13 reports are assessed as probable sunspot observations, of which 11 can be dated to within a year. Of these, auroral records suggest that up to six may be associated with possible geomagnetic storms. An apparent match in the timing of seven western observations with sunspot records from East Asia is identified and its implications are discussed.

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.

Prominence latitudes were used to track the positions of solar magnetic field boundaries over eight consecutive years. Equatorial zone boundaries moved towards the solar equator, accompanying sunspot active regions, until solar activity began to decline. Polar zone boundary migration towards the solar poles coincided with N/S magnetic field reversal, with polar ‘crowns’ forming in 2013/2014. Day-to-day prominence positions delineated field boundary orientation, which changed appreciably as the solar cycle progressed.

Gyulbudaghian’s Nebula is one of a small number of nebulae that clearly changes in appearance on timescales of months or years. It is associated with the pre-main sequence star PV Cephei and can take on a range of appearances. When PV Cephei is dim, only a faint and diffuse nebulosity is visible with CCDs, but at other times it can be detected in a 0.35m telescope visually. We report on the changes within the nebula observed from 2009 July to 2015 November by members of the BAA Deep Sky Section, using a diverse range of telescopes and cameras. Most of the observations were undertaken without filters, but they have been scaled and resampled to provide indicative trends in brightness for different parts of the nebula.

A team of 110 observers contributed nearly 6,000 observations at this aphelic opposition. Part I discusses albedo features and dust storms, as well as some highly unusual terminator events. Following the 2007 global dust storm, a number of albedo markings were still returning to their customary shapes. Solis Lacus had not yet recovered its 2005 form, but E. Noachis and many other features had returned to normal. There was a succession of minor dust storms over and around the N. polar cap in 2012 January–April, while it was just possible to detect the aftermath of a regional storm centred upon Hellas that had been imaged from martian orbit in 2012 November.