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Since the invention of the telescope, observers of Venus have often reported irregularities in the shape of the planet’s terminator and cusps. Some of these, such as terminator undulations, might be easily ascribed to poor seeing conditions; others, such as cusp extensions near inferior conjunction, are undoubtedly real and evidence of Venus’s atmosphere. This paper considers a third category: detached points of light recorded by several observers at the cusps of the planet, explained by some as high mountain peaks catching the sunlight. Among those who argued for the existence of such mountains was Johann Schröter, a stance that brought him into conflict with the views of William Herschel. Nowadays the ‘ghost mountains of Venus’ are seen for what they are: an illusion encouraged by a growing belief in the plurality of Earth-like worlds.

In Part I we described the interplay of airborne and settled dust with surface features. Here we review meteorological phenomena. Seasonal date limits for the Equatorial Cloud Band and orographic clouds were similar to past years. Despite an unfavourable value of tilt, north polar spiral clouds were witnessed during Ls = 126–153°. Frontal systems, in the form of bands of clouds inclined to the equator and moving off the N. polar region, were recorded. Observers watched to see if the near-opposition coincidence of the sub-Earth and subsolar latitudes on 2016 May 20–21 would result in ‘flashes’ from the Schiaparelli crater in Edom, as in 2001, but the +10° coincidence in the latitude fell too far north, and none were reported. The detachment of Olympia from the NPC occurred by Ls = 72°. The N. polar cap was progressively covered by the hood during Ls = 163–172°, later than in 2014, while the cap summer remnant was larger in 2016; the recession was less extensive than in 2014. Novus Mons separated from the shrin

Observations of Neptune, obtained both visually and by imaging in 2014 and 2015, are presented. In both years, long-lived bright atmospheric features on the planet were detected. For 2015, the daily drift of a major bright storm over a period of four months was determined.

This report describes observations of Uranus made during the 2015 apparition and subsequently submitted to the Section. Throughout this apparition, specific bright zones and dark belts were recorded both visually and digitally, and some variations of detail within them were identified.

‘Reggie’ Waterfield was the BAA’s 33rd president and its most prolific comet photographer from the 1930s to the 1980s. He was also an eclipse chaser and a leading haematologist. Part II covers the World War II era, Reggie’s fight back from a devastating illness, his BAA presidency, and the establishment of a dedicated team of comet photography assistants. The numbering of figures and references continues consecutively from those in Part I [131(3), 158–170 (2021)].

The opposition of 2016 May 22, during Martian Year 33, was the last in a series of aphelic approaches. There had been no obvious albedo changes since the previous opposition. The light yellow area of dust fallout on the NW side of Elysium showed an obvious opposition brightening, and there was also a brightening of the outer rim of Olympus Mons. Three of the various dust storms commenced in unusual or unique locations: in particular, a Regional one in SW Arcadia, and two around Mare Sirenum. A darkening and broadening of Mare Serpentis and a reappearance of Pandorae Fretum resulted from a Regional storm in September. There was no planet-encircling event, but just beyond the recognised seasonal limit for this phenomenon, two Regional events began in the north and expanded in the south; these occurred unusually close together in time. Part II will discuss meteorological aspects and the behaviour of the polar regions.

Presented here is an analysis and discussion of observations made of the nocturnal hemisphere during the 2019–’20 eastern elongation of Venus. These observations of the infrared thermal emission are crucial to the Section’s aim of investigating active volcanism on the planet. We also discuss research by professional astronomers at the Swiss Federal Institute of Technology, supporting the idea of active volcanism, and how the results obtained by Section members thus far support this conjecture.

The 2017–’19 primary eclipse of the red supergiant star VV Cephei has been monitored with low-resolution spectroscopy, by following changes in the hydrogen Balmer emission lines in the spectrum. A number of characteristics of the binary system are derived from the high cadence of observations, including a surprising estimate of 7,425 days for the orbital period since the midpoint of the last eclipse. The appearance of the spectrum near mid-eclipse has also provided a means to estimate interstellar reddening.

This report covers observations of Venus made by Section members during the 2019–’20 eastern elongation. Part I covers observations of the dayside; various features are discussed, including cloud formations and unusual atmospheric phenomena which occurred during this time. Using phase estimates, a date for dichotomy is established, and observations made near inferior conjunction are examined.

A summary of noctilucent cloud activity recorded during the 2019 northern hemisphere observing season.