Papers – Page 21 – British Astronomical Association

An oddity in the times of the Moon’s perigees

The times of the passage of the Moon through perigee repeat near the same calendar dates after four years. Yet the time intervals show an odd variation.

Noctilucent cloud over Britain and Western Europe, 2013–2014

A summary of observations of noctilucent cloud reported to the BAA in the 2013 and 2014 NLC seasons.

Patrick Henry Hepburn (1873 − 1929) – Part II: A decade of highs and lows

The life and times of one of the BAA’s most extraordinary Presidents and eclipse chasers is described, including his fascination with the rings of Saturn, his remarkable physical and mental stamina, his complex home life and his tragic demise.

Analysis of a Perseid fireball spectrum

Analysis is presented of a Perseid fireball spectrum recorded by videography on the night of 2013 August 12/13. Two significantly different spectra were obtained in one of the video frames, which we interpret as being due to an afterglow following an end flare of the fireball and emission from the surviving fragment.

Outbursts of the dwarf nova CSS 121005:212625+201948 in Pegasus

A monitoring programme of CSS 121005:212625+201948 covering nearly two observing seasons has shown that it is a typical SU UMa dwarf nova, but has one of the shortest supercycles of its class.

Saturn in 1999−2000

A report of the Saturn Section (Director: M. Foulkes)

Patrick Henry Hepburn (1873−1929) – Part I: Solicitor, Eclipse-chaser and Major

SN2008S – A new class of optical transient in NGC 6946: an amateur discovery

The purpose of this paper is to bring to the attention of the amateur astronomical community the writer’s discovery of a previously unknown class of object, the significance of which does not appear to have been reported in amateur publications.

Rømer revisited: A modern estimation of the speed of light from observations of Jupiter’s Galilean satellites

Ole Rømer (1644−1710) is remembered today for establishing, from observations of eclipses of the Galilean satellites of Jupiter, that the velocity of light is finite. This paper describes the use of amateur timings of Galilean eclipses observed during 2012−’14 to recreate Rømer’s work, together with a theoretical investigation of the accuracy of such approaches for estimating the speed of light.

A new and improved ephemeris for the hot subdwarf eclipsing binary SDSS J082053.53+000843.4

SDSS J082053.53+000843.4, for brevity here referred to as J08205, is a 15th magnitude short period, 0.0962404(1)d (~2h 18.6m), detached eclipsing