The Journal of the British Astronomical Association

Volume 114, No.4: 2004 August


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

On the cover: Cassini-Huygens arrives at Saturn

Following a seven-year journey through the solar system, the NASA spacecraft Cassini, carrying the ESA Titan probe Huygens, arrived at Saturn on 2004 July 1. With a flawlessly executed manoeuvre and 95-minute engine burn the spacecraft passed twice through Saturn's rings and took up orbit around the planet, ready for its four-year mission to study the Saturnian system. The cover shows Saturn's atmosphere and rings, imaged on 2004 May 15 from a distance of 24.7 million km; and three closeup images recorded during the ring plane crossing. Clockwise from right: density waves and unexpected detail in the A ring, exquisitely delicate patterning in the F ring, and the Cassini Division, seen from the unlit side of the rings. NASA/JPL/Space Science Institute. [Hazel McGee and Nick James represented the BAA at JPL during this historic event, and will report further in future issues of the Journal.].

The transit of Venus

Selected images of the Venus transit from BAA members, and details of how you can contribute to the BAA record of the event.

Notes and News

Completing the wish list (Tom Boles) / Prepare for the Perseids! (Neil Bone) / Aurora Section (R. J. Livesey) / Nearest and farthest (Andrew Hollis) / Visual observations of Mercury in 2003: First interim report (Mario Frassati) / Solar Section (Geoff Elston) / 'Encouraging progress' for Armagh Observatory's dark sky campaign (John McFarland, Mark E. Bailey & Apostolos A. Christou)

Observers' Forum

  • A massive solar prominence ... Lee Macdonald
  • Jupiter with a Webcam ... David Tyler
  • The lunar eclipse of 2004 May 4... Michael Foulkes and Damian Peach

  • Main articles

    The ultimate location for amateur astronomy?... Damian Peach

    The Canary Islands are well known to the professional community as one of the world's finest observing locations, but how does the observing fare for the amateur observer at sea level? (5pp)

    Jupiter in 2000/2001. Part I: Visible wavelengths - Jupiter during the Cassini encounter ... John Rogers, Hans-Joerg Mettig, Damian Peach & Michael Foulkes

    The main changes on Jupiter in 2000 were the disappearance of the dark band and festoons in the Equatorial Zone, and the broadening of the North Equatorial Belt (NEB) into the North Tropical Zone. While dark projections on the southern NEB diminished in number, irregular projections from the northern NEB eventually constituted a classical expansion event which was complete by the start of 2001, and the expanded belt was pockmarked with dark 'barges' and white ovals.
    Most of the major spots had persisted from the previous apparition, especially anticyclonic ovals, and their drifts, circulations, and appearances were largely unchanged. These included not only the Great Red Spot and a brown ring in the S. Tropical domain, but also anticyclonic white ovals in almost every other domain. Some of these, in latitudes ranging from the South Polar region to the N.N. Temperate region, apparently persisted between apparitions in spite of showing large and sudden changes in their drift rates.
    Outbreaks of dark spots were continuing in the SEBs, NTBs, and NNTBs jetstreams. In addition, we detected several spots moving in the SSTBn jetstream, which has rarely been detected from Earth, and one each in the NTBn, NNTBn, and N5TBs jetstreams, which have never previously been detected from Earth.
    The highlight of the apparition was the Cassini spacecraft flyby. Cassini images revealed details of all the spots and circulations that we recorded; examples are presented in an Appendix. Observations at non-visible wavelengths, from amateur and professional observers and from Cassini, will be presented in Parts II and III of this report. (22pp)

    Observing eclipsing variables: a beginner's guide ... Tony Markham

    The General Catalogue of Variable Stars (GCVS) lists many different classes of variable star. Some of these are well known and contain many members; others are more obscure and contain only a few examples. However, it is also possible to split variable stars into just two basic categories: the intrinsic variables - stars like Mira variables, Cepheid variables, novae and supernovae - in which the stars themselves are varying in brightness, or the extrinsic variables, in which the individual stars themselves don't actually vary, and prominent among these are the eclipsing variables. (5pp)

    Visual observation of meteors ... Neil Bone

    The recent spell of enhanced activity in the Leonid shower, culminating in storms in 1999, 2001 and 2002, has generated considerable interest in meteor observing. Some of the Association's most experienced observers have used the opportunity afforded by this high activity to advance studies of the Leonid meteor stream. Special mention should be made of the photographic and video work carried out in collaboration with Dutch and Czech observers by Steve Evans and Andrew Elliott, which continues to yield new orbital data for Leonid meteoroids. For others, the spectacle was simply one to be enjoyed - an astronomical rarity to collect alongside eclipses, transits and so forth.
    Visual meteor observing is, rightly, seen as an easy field in which to partake, but there are some important points to remember - as I shall outline here - which will make the resulting records suitable for more detailed analysis that can reveal interesting features of how the regular annual showers behave, and sometimes change, over various timescales. (4pp)

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


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  • NASA'S Voyager missions - exploring the outer solar system and beyond by Ben Evans & David M. Harland. Springer/Praxis, 2004. ISBN 1-85233-745-1. Pp xviv +284, 24.50 (pbk). Reviewed by David Graham
  • Cometography: A catalog of comets. Volume 2: 1800-1899 by Gary W. Kronk. Cambridge University Press, 2004. ISBN 0-521-58505-8. Pp xiii + 837, 120.00 (hbk). Reviewed by Guy Hurst
  • The Maunder Minimum and the variable Sun-Earth connection by Willie Wei-Hock Soon and Steven H. Yaskell. World Scientific Publishing, 2004. ISBN 981-238-274-7, 57.00 (hbk); 981-238-275-5, 28.00 (pbk). Pp xviii + 278. Reviewed by David Gavine

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    Meeting reports

  • Ordinary Meeting 2003 November 29 ... Dominic Ford

  • BAA Update

  • Obituary: Jeremy David Cook (1933-2003) ... Anthony C. Cook

  • Sky notes for 2004 August & September

      by Neil Bone

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