The Journal of the British Astronomical Association

Volume 117, No.5: 2007 October

Summary contents page

Detailed contents: Notes and News / Articles / Observers' Forum / Reviews / Letters / Meetings / BAA Update

Cover image

M20 (NGC 6514), the cluster and nebula complex in Sagittarius known as the Trifid Nebula. Intes Micro MK67DL 150mm f/12 Mak-Cass reduced to ~f/6 via focal reducer, with SXV-H9 CCD camera and Astronomik IIC RGB filters. Imaged from Marina di Tertenia, Sardinia, in August 2004 by BAA Deep Sky Section member Andrea Tasselli.

Notes and News

From the President (Richard Miles ) / Satellite antenna dish acquired for use by the BAA (Terry Ashton) / Dark skies for the Leonids in November (Neil Bone ) / Solar Section (Lyn Smith) / The climax of Jupiter's global upheaval (John Rogers) / Part-time Accountant required for the BAA / The variability of Venusian markings in the visual waveband (Richard McKim)

Refereed articles

The 2008 August 1 total solar eclipse... Sheridan Williams

This eclipse traverses northern Canada, the Arctic, northern Russia, Kazakhstan, Mongolia and ends in China. To my mind a total solar eclipse is the most moving and spectacular experience on Earth, and should be near the top of your list of things to do before you die. It is difficult to explain to those who have never seen one, why a total eclipse unleashes such vivid emotions.
There are only about seventy total solar eclipses per century, and there was none in 2007. The next three after 2008 are in 2009, 2010 and 2012, but none of these has an observing location where weather prospects are better than for the Gobi Desert in 2008. For this reason I thoroughly recommend that you head off to China, as you won't get another weather-favourable opportunity until 2013, and unfortunately that will be a very short eclipse in Central Africa.

Scaling the magnitude: the fall and rise of N. R. Pogson... Vishnu Reddy, Keith Snedegar & B. R. Kumar

A study of the life and work of the neglected British astronomer N. R. Pogson, whose magnitude scale is still the standard formulation for normal use.

The Ashen Light of Venus: A century of observations by McEwen and Moore... Richard McKim & Patrick Moore

This paper is a catalogue and analysis of the Ashen Light sightings from two remarkably long series of Venus observations held in the BAA Mercury & Venus Section archives spanning 1892 to 1999. The records comprise overlapping series of visual records by the first two Directors of the Section, Henry McEwen and Patrick Moore. The Ashen Light was seen during 25 of the 56 adequately-observed elongations. By analysing the results in terms of the eight-year 'cycle' of Venus elongations we demonstrate that the Ashen Light's visibility does not simply depend upon terrestrial viewing conditions: those elongations that permitted Venus to be viewed at reasonable altitude against a dark sky were not the only occasions when the Light was well seen. At times the phenomenon can become especially conspicuous, as in 1953 and 1956 (when it was visible semi-continuously for more than a month), and in 1895, 1935, 1940, 1957, 1980 and 1988 (where there were fewer good sightings). There also exist long intervals where, despite excellent conditions and observational coverage, the Ashen Light has remained remarkably obscure.

Click here to obtain a PDF file of any of these articles

Report of the Council and Accounts for the year 2006-2007

BAA Update

  • Meeting of the Asteroids & Remote Planets Section, Newbury, 2007 June 2 ... Roger Dymock
  • Obituary: Frank M. Bateson OBE, FRAS, FRASNZ, 1909-2007 ... Grant Christie & Roger Pickard
  • Obituary: John Charles Clint Larard, 1937-2007 ... Guy M. Hurst

  • Letters

  • The oldest identified classical nova ... Göran H. I. Johannson
  • The apochromatic dialyte refracting telescope ... John Wall
  • Venus in transit, daytime seeing, and images of Mercury ... Richard McKim
  • Discovery and nomenclature of the Mare Orientale ... Patrick Moore
  • Memories of Michael Gadsden ... Wilfried Schröder

  • Observers' Forum

  • Daytime photometry of stars and planets ... Richard Miles
  • A daylight occultation of Venus ... Richard McKim

  • Observing the Cat's Eye Nebula ... Stewart L. Moore

  • Supernova 2007af in NGC 5584 ... Guy M. Hurst
  • [Reappearance of Venus from occultation by the Moon, 2007 June 18 at 15:30 UT. Image by John Vetterlein]


  • Understanding variable stars by John R. Percy
    Cambridge University Press, 2007. ISBN 0-521-23253-8. Pp xxi + 350, £30.00 (hbk).
    Reviewed by Chris Jones
  • Introduction to astronomical photometry by Edwin Budding & Osman Demircan
    Cambridge University Press, 2007. ISBN 0-521-84711-7. Pp xvi + 434, £45.00 (hbk).
    Reviewed by David Boyd

  • CLICK HERE to read scores more authoratitive book reviews from the BAA Journal

    In Association with

    Search for all your leisure needs at

  • Sky notes for 2007 October & November
  •   by Neil Bone

    Back to top of page

    Go to the BAA Journal home page