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This report describes and analyses the observations of the brighter or more interesting comets discovered or at perihelion during 2013, 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 Comet Section’s visual observations web pages.

This paper considers past and future appearances of the southern constellation of Crux in the skies of Britain.

The southern boundary of Mars’ North Polar Hood (NPH) was measured from 585 Earth-based images made between 2001 and 2016. This analysis covers the late summer, autumn and winter seasons for Mars’ northern hemisphere.

James Henry Worthington became a prominent amateur astronomer during the years preceding the Great War, mainly because of his expeditions to distant solar eclipse tracks and observatory sites, but also because of his interest in the Martian ‘canals’ and his friendship with Percival Lowell. Just prior to the start of the War he built a major observatory at Four Marks in Hampshire, which he generously invited BAA members to use whenever they wished, at least until he moved permanently to the USA.

Results from the 2012 June solar transit of Venus are illustrated and discussed, and make an interesting comparison with our recent report on the 2016 transit of Mercury. As in previous years, observers were able to time the contacts, to see the ‘Black Drop’ effect (caused by inadequate resolution, but often enhanced by turbulence) and to record the ring of light around the unilluminated limb at both ingress and egress. This will be the last transit of Venus until 2117 Dec 11, unless we include the event of 2020 Jun 3, when the planet will be silhouetted against the solar corona.

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.