The Journal of the British Astronomical Association

Volume 121, No.2: 2011 April

Summary contents page

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

Cover image
NGC 2239, the Rosette Nebula in Monoceros. Mapped colour, 200 min Ha (r), 150 min S11 (g) & 90 min Hb (b). ST10 on Takahashi FSQ, steered by ST8 on 406mm RCOS with adaptive optics.  Gordon Rogers, 2011 March 4–8

Notes and News

From the President (David Boyd) / Aurora Section (Ken Kennedy) / Uranus & Neptune: an interim report on the 2010 apparition (Mike Foulkes) / Solar Section (Lyn Smith) / A second interim report of the 2010/2011 Saturn apparition (Mike Foulkes) / An abundance of SIDs (Paul Hyde)

The Presidential Address, 2010

Pro-am collaboration in astronomy – past, present and future
... David Boyd

The 2010 BAA Presidential Address, given on 2010 October 27 at the Royal Astronomical Society Lecture Theatre, Burlington House, Piccadilly, London W1

Refereed papers

Making visual lunar and planetary observations at the Lowell Observatory ... Paul Abel

In the last year or so, I have been interested in the idea of using a small to medium sized professional telescope for making visual observations of the Moon and planets. In Europe and the US there are a number of good refractors which, if they are used at all, provide little more than occasional views of the heavens to interested members of the public. Those are the fortunate ones; many more seem to have been allowed to fall into disrepair (Herstmonceux for example) and languish in a state of limbo, perhaps waiting to become a hazard to health and safety so that they can then be humanely culled. The great Meudon refractor has been out of action since the early 1990s, but at least the dome has been restored and money has been allocated for the refractor be refurbished. We can only hope the telescope might be back in action relatively soon.
While it may be the case that, in the current economic climate, it is not cost effective to upgrade these instruments with the latest CCD software and technology, I have always thought that these great stalwarts of astronomical history deserve a rather better retirement, and could come to play an increasingly important role in the activities of the visual amateur astronomer. Recently, I began to wonder just how hard it would be to get some time on such a telescope using only the funds available to amateurs. I decided to test the water by getting time on a famous telescope: the Alvan Clark refractor at the Lowell Observatory in Arizona.

The orbital and superhump periods of the deeply eclipsing dwarf nova SDSS J150240.98+333423.9
Jeremy Shears et al.

The speed of the lunar shadow on Earth during solar eclipses
... Wilhelm Carton

Currently there is no direct method to calculate the speed with which the lunar shadow rushes past points on the central line during a total or annular solar eclipse. Two well-known specialists in the field of eclipse computations admit that they are forced to use a ‘two-sites difference’ method. I present here a method inspired by my background in construction engineering. The technique decomposes vector quantities (forces, velocities) into their components along a 3-D system of rectangular axes, finally composing the three component sums to obtain the result.

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  • Asteroids and dwarf planets and how to observe them by Roger Dymock
    Springer, 2010. ISBN 978-1-4419-6438-0. Pp. xiii + 248, £27.50 (pbk, available from BAA Sales).
    Reviewed by Ted Bowell
  • Cosmic Challenge: The ultimate observing list for amateurs by Philip S. Harrington
    Cambridge University Press, 2011. ISBN 978-0521-89936-9. pp xi + 469, £27.50 (hbk).
    Reviewed by Callum Potter
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    BAA Update

  • Meeting of the Historical Section, 2010 November 27 ... Lee Macdonald

  • Obituary: Elmer J. Reese, 1919-2010 ... John H. Rogers & Reta F. Beebe
  • Obituary: Valerie Ann White, 1952-2010 ... Sheridan Williams

  • Observers' Forum

  • The Owl Nebula, M97 ... Stewart L. Moore
  • A useful DSLR camera modification ... Jack Martin
  • M97, the Owl Nebula, imaged by Andrea Tasselli, Leicester, UK.

    Sky notes for 2011 April & May by Callum Potter

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