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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.

‘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 I covers Reggie’s earliest years, the three years he spent abroad in Baltimore, his gruelling eclipse expeditions and his friendships with W. H. Steavenson and others.

Using personal white-light disc drawings of the Sun, it is assessed that some 8% of all sunspot groups observed during the 10 years from 2009 to 2018 have not been assigned an NOAA active region number. This paper examines these groups to try to identify why this might be the case.

In Part II we describe the usual seasonal meteorological indicators such as the Tharsis orographic clouds and the Equatorial Cloud Band (ECB). The ECB was observed to be complete during Ls = 051 to 145° and observations of the Syrtis Blue Cloud were frequently made. In 2014 the N. polar spiral clouds at the edge of the summer cap were particularly well observed from Ls = 117°. Their morphology was observed to change with time, and those clouds over Baltia occurred seasonally earlier than similar features over Utopia. The transition from N. polar cap to hood occurred during Ls = 153 to 162°. The early stages of the recession of the N. polar cap occurred too close to solar conjunction to be well observed, but the later stages were followed quantitatively and the data compared with previous years.

The Gaia space observatory provides parallax values for stars, allowing us to determine their distances. Young star clusters are located close to the galactic plane where their formation took place. The distances of fifty young clusters have been computed, allowing us to see how they are distributed in the Milky Way galaxy. This distribution provides us with evidence of the shapes and distances of the spiral arms in which they were formed.

In this study we examine a lunar dome, termed Laplace 1 (L1), identified using telescopic, LROC WAC and Chandrayaan-1 Moon Mineralogy Mapper imagery; Mineral Mapper reflectance data acquired by the JAXA probe SELENE/Kaguya; the LOLA digital elevation model and the LROC WAC-based GLD100 digital terrain model. The dome lies at coordinates 48.57°N and 26.37°W, about 36km south-east of the crater Maupertuis. It has a base diameter of 7.6 ± 0.3km and a maximum height of 230 ± 20m, resulting in a slope angle of 3.4 ± 0.3°. Spectral data indicate a basaltic composition. We assess the regional geology and infer the physical conditions under which the dome originated. L1 is not reported in lunar dome catalogues; hence our study demonstrates that high-resolution CCD imagery is useful for the recognition of non-catalogued domes. The main goal of this paper is to promote serious lunar research among dedicated amateur astronomers.

David Sinden, an amateur astronomer and former member of the BAA, was the last in a line of opticians that can be traced back to Thomas Grubb. For many years he was chief optician at Sir Howard Grubb, Parsons and Company where he worked on optics for some of the world’s largest telescopes made at the time. He went on to establish his own business, the Sinden Optical Company, before his untimely death in 2005. He was a highly respected and skilled optician whose achievements were considerable. Many of his optics are still in daily use in observatories around the world.