The Journal of the British Astronomical Association

Volume 114, No.2: 2004 April

On this page: Notes and News / Articles / Observers' Forum / Reviews / Letters / Meetings / BAA Update

On the cover: Rosetta is on its way

The European Space Agency's comet orbiter Rosetta was successfully launched on 2004 March 2 by an Ariane 5G launch vehicle from Kourou, French Guiana. Following a ten-year journey through the solar system, Rosetta will go into orbit around Comet 67P/Churyumov-Gerasimenko in early 2014, and release a lander onto the comet's surface. The orbiter and lander each carry a large complement of scientific experiments designed to complete the most detailed study of a comet ever attempted. Background: An artist's impression of the Rosetta lander as it prepares to touch down on the active cometary nucleus. Images: ESA

Notes and News

From the President (Tom Boles) / 'Lukewarm' government response to Parliamentary Select Committee report (Bob Mizon, Campaign for Dark Skies) / Mars in 2003: Final interim report (Richard McKim) / Solar Section (Geoff Elston) / Saturn, 2003-'04 apparition: First interim report (David Graham & Damian Peach) / Aurora Section (R. J. Livesey)
Solar viewers for the transit of Venus

Main articles

An 'off the shelf' plastic runoff shed observatory ... Martin Mobberley

Runoff sheds and runoff roofs have always appealed to me, because they are inexpensive, simple to build and, on warm nights in summer, allow the observer to see the whole sky at once (including impending cloud and bright meteors). They also do not require planning permission or invoke complaints from neighbours. For supernova patrolling a dome would have to be automated, and for planetary observing a dome traps the daytime heat, ruining atmospheric seeing. An additional consideration in my case, as a keen comet imager, is that I must be able to get as low as possible to the horizon without observatory walls impeding the view.

After twenty-three years of building and using runoff sheds, experience had taught me that the new shed must be as small, rigid and lightweight as possible, and the travel up and down the rails must be flawless. A durable, lightweight, runoff shed observatory, constructed using a hardware store garden shed, and housing a robotic Schmidt-Cassegrain telescope, is described. (5pp)

The influence of exit pupil diameter on visual acuity - a personal investigation ... Andrew Langley An extended object and a point source test pattern were observed through a range of apertures simulating exit pupils of different sizes. Clarity of vision was found to vary as a function of 'exit pupil' size and nature of the test object. Optimum definition was obtained with apertures of about 3mm for extended objects and a little less for point sources of moderate brightness. Bright point sources were more poorly resolved at all apertures because of glare. The results are indicative that low power instruments with exit pupils around 3mm and of relatively modest aperture, will yield superior definition than larger instruments of similar magnification. At higher powers small aperture instruments (within their diffraction limited capabilities) would also be expected to give better definition of bright double stars than larger instruments at comparable magnifications. (5pp) A short history of Hamburg Observatory ... Stuart R. Anderson & Dieter Engels This paper's aim is to provide a short history of Hamburg Observatory, its astronomers and instruments, its contribution to astronomy and to the popularisation and education of astronomy in Germany. (10pp) The Jupiter Section programme in the new century ... John H. Rogers The advances in imaging technology in recent years have transformed amateur planetary astronomy. CCD images now provide almost continuous high-resolution coverage of Jupiter at a level previously obtained only in intermittent professional projects. This progress has necessitated a reappraisal of the observing programme of the Jupiter Section. (7pp)

Solar photography with a small telescope ... Lee Macdonald

The Sun is one of the most fascinating targets in the sky for the amateur astronomer and also one of the easiest objects to observe. It is intensively monitored night and day by professional astronomers, so the amateur is very unlikely to make a major discovery on the Sun, as is possible in other fields, such as supernova hunting. But the amateur solar photographer can still make him or herself useful and have a great deal of fun recording the ever-changing panorama of sunspots and other solar features.

(Copies of any of these articles may be ordered from the BAA office.)

Reviews

(Here is an easy way to obtain your astronomy books, and help the BAA at the same time! Any books or other goods ordered from Amazon after following a link from this site - not just books reviewed here - will generate a small commission for the BAA.)

The Modern Moon - a personal view by Charles A. Wood
Sky Publishing Corporation, 2003. ISBN 0-933346-99-9, Pp xix+209. $49.50 (hbk).
Reviewed by Hazel Collett

Exploring Mercury: The Iron Planet by Robert G. Strom & Ann L. Sprague
Springer/Praxis, 2003. ISBN 1-85233-731-1. Pp xxx + 216 (pbk), Ł24.50.
Reviewed by Ron Toft