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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.

The twelve-year lightcurve of the nova-like cataclysmic variable HS 0506+7725 between 2006 April & 2018 November is presented. This shows that the star spends most of the time in a normal state at about magnitude 14.7, but multiple excursions to a fainter state at magnitude 16.0–17.0 were apparent. These normal-state/low-state transitions of up to 2.3 magnitudes are typical of the VY Scl subclass of CVs. In the case of the best characterised fading episode, both the fading and the subseqent return to normal brightness were observed; the complete transition lasted about 43 days. Further monitoring of this system by amateur astronomers is encouraged to identify and characterise future low states.

Using observations submitted to the BAA Solar Section, the largest sunspot groups of Solar Cycle 24 are discussed and example images shown. The characteristics of the cycle are also described and a comparison is made between the sizes of its larger sunspot groups and those of previous cycles, stretching back over 100 years.

Multicolour broadband photometry and flux-calibrated low-resolution spectroscopy, obtained between 2014 & 2018, are used to investigate the behaviour of the highly variable Herbig Ae star RR Tauri.

John Glasby was a popular Director of the BAA Variable Star Section from 1965–’71; an exciting period during which George Alcock discovered three novae. Glasby’s legacy is still felt today, because he steered the Section towards more observations of cataclysmic variables as well as starting a binocular variable star programme. He also wrote three books on the subject of variable star observing, filling a major gap in the literature, along with hundreds of works of pulp fiction. Unfortunately, so much controversy surrounded major errors in his BAA reports that any positive contribution he did make has long since been forgotten. This paper is an attempt to unravel the complex enigma of John Glasby’s directorship and the set of unfortunate circumstances that damaged his astronomical reputation.

Data regarding (514107) 2015 BZ509, a retrograde co-orbital asteroid of the planet Jupiter, is presented and discussed.

Paper II described the extreme changes in Jupiter’s North Equatorial Belt (NEB) which took place in 2011–’12: quiescence, narrowing and fading of the belt, along with acceleration of the prograde NEBs jet to super-fast speed. Here we describe how this anomalous state was terminated in 2012, in a rapid and vigorous disturbance known as an NEB Revival – the first in living memory. At the same time, the North Temperate Belt (NTB) had entered a similar preparatory state, which was terminated by an NTB Revival initiated by a typical outbreak on the super-fast NTBs jet. The two concurrent Revivals appeared to constitute a ‘great northern upheaval’ extending from the equator to ~38°N, which may have been the first such event ever recorded. We compare this dual event with the more typical ‘global upheavals’, which consist of near-simultaneous Revivals of the NTB and the South Equatorial Belt (SEB), along with equatorial coloration. We also discuss the current understanding of global upheavals.