The opposition of Mars, 2010: Part II

In Part II we discuss white clouds and the polar regions. The equatorial cloud band (ECB) was well observed from Ls= 001° onward. The behaviour of the orographic clouds over the great volcanoes was seasonally normal, in the absence of any large dust disturbance. We saw the Tharsis orographics from Ls= 011°, and the Olympus Mons orographic from Ls= 019°. As with the ECB, observations did not continue late enough to establish their seasonal decline. The 2009-’10 N. polar cap recession was followed in detail nearly as far as the summer remnant stage.

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The brighter comets of 2012

This report describes and analyses the observations of the brighter or more interesting comets discovered or at perihelion during 2012, concentrating on those with visual observations. Magnitude parameters are given for all comets with observations. Any evolution in the magnitude parameters of those periodic comets with multiple returns is discussed. Additional information on the comets discussed here and on other comets seen or at perihelion during the year may be found on the Section visual observations web pages.

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Saturn in the 2008/2009 apparition: Part I

This report describes the observations of Saturn made by Saturn Section members during the 2008/2009 apparition. During this apparition, the rings were edge-on to the Sun and Earth on 2009 Aug 11 and Sep 4 respectively

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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.

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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.

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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.

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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).

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