The Journal of the British Astronomical Association

Volume 117, No.4: 2007 August

Summary contents page

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

Cover image

The European Space Agency GAIA mission (Global Astrometric Interferometer for Astrophysics) is scheduled for launch in late 2011. This combined astrometric/photometric facility is planned to extend to at least the year 2020 and is expected to set new standards in astrometry & photometry for many years to come. See Richard Miles' Presidential Address A light history of photometry on page 172. (? ESA; illustration by Medialab)

Notes and News

From the President (Richard Miles ) / Perseids set for a favourable showing (Neil Bone) / Solar Section (Lyn Smith ) / Asteroids & Remote Planets Section (Roger Dymock) / Another supernova for Tom Boles (Stewart L. Moore) / Part-time Accountant required for the BAA / Mercury in transit, 2006 November 8-9 (Richard McKim) / A daylight occultation of Saturn (Mike Foulkes)

Photo: A composite image of Saturn at egress adjacent to the Mare Smythii at 20h 18m 21s UT, by Peter Lawrence. 356mm Schmidt-Cassegrain (C14) at F11. Luminera SKYnyx-2-0M camera with Astronomik red filter. The lunar image was taken at 20h 19m 15s UT.

The 2006 BAA Presidential Address

A light history of photometry: from Hipparchus to the Hubble Space Telescope... Richard Miles

Science, and in particular that branch known as physics, has its basis in measurement: that is quantifying a particular phenomenon so that it can be more fully described mathematically. In the case of light, we can use our own eyes to assess the phenomenon, but how can we describe what we see by way of numbers? How can we measure the amount of light we are experiencing? This is what I would like you to understand by way of the term 'photometry'. Let us go on a journey through time past and trace the developments that have taken place in photometry over the years.
Note that in the interest of brevity I shall limit this account to the measurement of light in the visual range of the spectrum. This will mean omitting the study of spectra and spectrophotometry, an examination of which might otherwise prove to be a distraction from the main theme, which is one of technological progress and human achievement.

Lightcurve of the eclipsing binary AR Aurigae recorded by
the author from Mouldsworth Observatory, Cheshire, in 1983.

Refereed articles

Trouvelot's threads: the 'murs enigmatiques' of Etienne Leopold Trouvelot... Nigel Longshaw

A brief biographical sketch of E. L. Trouvelot, with reference to a rather unusual phenomenon he observed in connection with the lunar crater Eudoxus on 1877 February 20, which he was later to term his 'Murs Enigmatiques' (enigmatic walls).

The aurora 2005... R. J. Livesey

This report summarises observations of the aurora relating to the northern hemisphere collected by members and correspondents of the Aurora Section in 2005.

Analysis of the first confirmed superoutburst of V337 Cygni in 2006 May... David Boyd, Tom Krajci, Jeremy Shears & Gary Poyner

During 2006 May the first confirmed superoutburst of the dwarf nova V337 Cygni was observed using unfiltered CCD photometry. The outburst reached a peak magnitude of 15.2 on May 22 and lasted 13 days before the object returned to quiescence at around magnitude 20. Time-series photometry revealed superhumps with a period of 0.07012 0.00033d and amplitude 0.1 magnitude, thereby establishing for the first time its UGSU classification. Astrometry of V337 Cyg in outburst determined an accurate position and enabled the identity of the star in quiescence to be confirmed.

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  • Finding Mercury in daylight ... Chris Hooker
  • The apochromatic dialyte refracting telescope ... Rick Blakley
  • Venus in 2004 ... Christopher Taylor
  • The myth of daylight poor seeing ... John C. Vetterlein

  • Observers' Forum

  • NGC 246: an overlooked planetary nebula in Cygnus ... Stewart L. Moore
  • DV UMa in outburst ... Roger Pickard & Ian Miller

  • [Photo of NGC 246 by Nick Hewitt]

    BAA Update

  • Meeting of the Variable Star Section, Edinburgh, 2007 May 5 ... Melvyn Taylor & Roger Pickard
  • A gallery of Section Directors ... Richard McKim
  • 200,000 variable star observations! ... Roger Pickard

  • Meetings

  • Ordinary Meeting, 2006 November 25 ... Roger Dymock
  • Ordinary Meeting and Christmas Lecture, 2006 December 16 ... Dominic Ford

  • Reviews

  • Nightwatch: A practical guide to viewing the Universe (4th edn) by Terence Dickinson
    A & C Black, 2006. ISBN 0-7136-7939-5. Pp 192, 29.99 (pbk).
    Reviewed by Martin Morgan-Taylor
  • The comet sweeper: Caroline Herschel's astronomical ambition by Claire Brock
    Icon Books, 2007. ISBN 1-84046-720-7. Pp x + 292, 9.99 (hbk).
    Reviewed by Lee Macdonald
  • The de Vaucouleurs atlas of galaxies by Ronald J. Buta, Harold G Corwin & Stephen C. Odewahn
    Cambridge University Press, 2007. ISBN 0-521-82048-0. Pp xii + 344, 70.00 (hbk).
    Reviewed by Stewart L. Moore

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  • Meetings Diary and notices
  • Sky notes for 2007 August & September
  •   by Neil Bone

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