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A method of daytime collimation of a Cassegrain-type reflecting telescope is described, which uses a circular target aligned on the optical axis of the primary mirror. Basic construction details are given for making a suitable target and a procedure is outlined for collimating both Schmidt–Cassegrain and Ritchey–Chrétien telescopes.

Four low resolution (R~1000) spectra were obtained of the RV Tauri-type variable AC Her during its rise from a deep minimum in July 2014. These show changes in spectral type and Balmer line equivalent width as the star brightened, consistent with earlier observations.

Edwin Alfred Holmes (1839-1919) is best remembered for his discovery of a bright comet in 1892, now known as Comet 17P/Holmes. An amateur astronomer and authority on optics, he was an original member of the BAA and contributed to its Journal and meetings for many years. As a prolific writer of letters to English Mechanic, he developed a reputation for his controversial and acerbic penmanship.

We present the 13-year lightcurve of HW Boo between 2001 May and 2014 May. We identified 12 outbursts, which typically lasted 2 to 5 days, with an amplitude of 2.7 to 3.6 magnitudes. We discuss whether HW Boo might be a dwarf nova of the SU UMa family or an Intermediate Polar, but further observations are needed to support classification.

This report describes and analyses observations of the brighter or more interesting comets discovered or at perihelion during 2005.

BAA observations between 1995 April and 1996 February are reviewed. Highlights of the apparition were observations of the phenomena of the triple ring-plane crossings by the Earth and the ring-plane crossing of the Sun, the results of which show that the predicted times were correct to within a few hours. Transits and shadow transits of Titan, Rhea, Dione and Tethys were observed. Several mutual satellite events were also observed, either visually or by means of CCD cameras. White spot activity could again be followed in the planet’s northern Equatorial Zone (EZ), though it was much reduced from 1994-’95: the long-enduring white spot (WS1) had survived solar conjunction and continued to move with a rotation period close to 10h 22m, as did another short-lived feature…

In 1839, Ebenezer Porter Mason (1819-1840) produced detailed drawings of the Omega Nebula (M17), the Trifid Nebula (M20) and the eastern part of the Veil Nebula. This paper reviews his life and his observations, comparing his results with those of the modern amateur astronomer.

The semiregular variable Z UMa experienced a particularly deep minimum at the end of 2014 March, followed by a three-month rise to maximum.