Papers – Page 16 – British Astronomical Association

RZ Cas lightcurve and orbital period variations

A binary star model for RZ Cas is fitted to a set of high quality electronic magnitude observations of recent minima, deriving in the process some of the parameters of the system. This lightcurve is then fitted to raw observational data from the BAA, AAVSO, AFOEV and VSOLJ in order to determine the times of minimum. These observed times of minimum supplemented by data from the Lichtenknecker database are then compared to expected times and are shown to be consistent with several significant long-term changes in the period.

The opposition of Mars, 2010: Part I

This report summarises over 8,000 observations by 149 observers between 2009 March and 2010 September, covering martian northern late autumn to winter, spring and early summer (Ls= 232-156°). Part I discusses dust storms and albedo features.

The strange world of V. Axel Firsoff (1910−1981)

Axel Firsoff was one of the most controversial theorists and letter writers in the BAA’s history, submitting huge amounts of correspondence to the Journal between 1956 and 1981 and serving on the Committee of the Terrestrial Planets Section from 1979 to 1981. He was also a successful author, writing more than 20 books from 1942 until his death. In addition, Firsoff was a skilful artist, an accomplished skier, a lunar and planetary observer and an early pioneer in the use of colour filters.

Spectroscopic observation of planetary nebulae

This paper describes how commercially available spectrographs can be used to identify and measure some basic characteristics of planetary nebulae.

Saturn, 2004-’05

The 2004-’05 apparition was very well observed, though the planet showed less atmospheric activity than in the previous apparition. Many images were obtained at visible, infrared, ultraviolet and methane band wavelengths. The planet was at opposition in Gemini on 2005 Jan 13, at declination +21°. Solar conjunctions occurred on 2004 Jul 8 and 2005 Jul 23. Our observers monitored the planet from 2004 Aug 15 (Gray) till 2005 Jun 9 (Yunoki).

Franz von Paula Gruithuisen (1774− 1852) and the ‘Lost City in the Moon’

In the early hours of the morning of July 12 in the year 1822, Franz von Paula Gruithuisen (1774–1852) turned his small telescope to the Moon. What greeted him at the eyepiece, in the environs of the crater named Schroeter, was nothing short of a revelation. The jumbled terrain, caught under raking illumination, coalesced into a regular arrangement which convinced the astronomer he had discovered evidence that the Moon was inhabited….

The BAA Memoirs: an introduction

With the publication of a DVD set of the BAA Memoirs during 2017, a short historical review of these publications seems timely. Most of the Memoirs presented the longer reports of the Observing Sections of the Association, and until just after World War II they were issued fairly frequently, with several numbers appearing every session. From the 1950s they became one-off publications, produced on increasingly rare occasions, with Section reports mostly appearing in the Journal. This article explains how these changes came about, and attempts to give an idea of the diverse nature of this series of lesser-known BAA publications.

The first recorded aurora australis?

This paper presents evidence for a probable aurora australis report and persistent recurrent solar activity in the year 1580.

Frank Wilsenham Hyde (1909-1984): Radio astronomer extraordinaire!

Frank Wilsenham Hyde was a popular character in the BAA from 1957 to 1966, receiving the Association’s Merlin Medal in 1963 and serving briefly as the Editor of the Journal from 1963 November to 1965 December. His extraordinary Radio Astronomy Observatory was the most advanced amateur facility in the UK during the 1960s, and the media even described it as ‘a miniature Jodrell Bank’. However, increasing financial problems led to his dramatic exit from the Association and the dismantling of his observatory in 1967.

Lunar eclipse brightness and the terrestrial atmosphere

This work presents a study of the brightness of 164 lunar eclipses which were observed between 1670 and 2015. Data were analysed via four equations, which we refer to as the Formulae of Colle Leone, named after the observatory with which the author is associated. Attention is given to the quantity of ozone in the stratosphere and to the total optical depth of the atmosphere. The optical depth is correlated with both volcanic phenomena and human activities. No evidence of a correlation was found between the optical depth and solar activity.