Reginald Lawson Waterfield (1900–1986), eclipse chaser & comet photographer extraordinaire: Part II: 1939–’86

‘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)].

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The opposition of Mars, 2016: Part I

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.

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The 2019–’20 eastern elongation of Venus, Part II: Observations of the nightside

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.

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Observing the 2017–’19 primary eclipse of VV Cephei with a low-resolution spectroscope

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.

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The 2019–’20 eastern elongation of Venus, Part I: Observations of the dayside

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.

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Sunspot groups without active region numbers

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.

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The opposition of Mars, 2014: Part II

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.

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Using Gaia DR2 data to determine the distances of young star clusters & their distribution in the galactic plane

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.

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