The Journal of the British Astronomical Association
Volume 109, No.4: 1999 August
List of Contents
On this page: Notes and News / Articles / Letters / Reviews / Meetings / Observers' Forum / BAA Update
Notes and News
SN 1999by: a bright supernova in NGC 2841 / The last days of Jupiter's white ovals? / From the President / Don't forget the Perseids this August... / Aurora Section / Solar Section
Articles
High resolution spectra and monochromatic images of a flaring 1991 Perseid meteor ... David Airey
During a Winston Churchill research fellowship visit to Tenerife, the author was fortunate to capture a polychromatic image and two spectra of a flaring, magnitude -4, Perseid meteor. One spectrum, obtained using an unusual reflection grating spectrograph design, captured meteor emission lines in the wavelength range 3920 to 4720Å at an average dispersion at the camera film plane of 16 Å/mm. Using a solar spectrum comparison technique for the analysis, 31 strong emission lines due to CaII, CaI, MgII, MgI and FeI have been positively identified. Analysis of an additional 54 weaker lines provides some evidence for the presence of CrII, CrI and FeII. The strength of the ion lines relative to the neutral lines indicates a high atmospheric entrance velocity for the meteor. Combination of a large dispersion and long focal length in the high resolution spectrograph enabled clear monochromatic images of the meteor flare to be obtained. Detailed differences between the meteor appearance in CaII and MgII light are revealed and discussed. (10pp)
Visual observations of the Perseid meteor shower in 1991 ... N. M. Bone
Analysis of the 1991 visual Perseid data from the Meteor Section files is presented as an appendix to the work of Dr D. R. Airey. (2 pp)
The comets of 1994 ... J. D. Shanklin
This report is the fifth in the annual series which gives for each comet: the discovery details, orbital data and general information, magnitude parameters and BAA Comet Section observations. Further details of the analysis techniques used in this report are given in an earlier paper. Ephemerides for the comets predicted to return during the year can be found in the BAA or ICQ Handbooks.(19 pp)
Sunspot cycle 22: A qualitative and quantitative analysis ... Frank Ventura & Tony Tanti
Sunspot activity between 1987 and 1996 is analysed using the Zurich classification of sunspots in order to check whether its quality changed during Cycle 22. The mean monthly intensity of the activity is also estimated from the types of sunspots and compared to the international sunspot index Ri. The results indicate no trend in the relative abundance of sunspots of types A, B, C, D and a combination of H and J, while there is a definite decrease in spots of types E, F and G. The high correlation between the monthly solar activity estimated from the types of sunspots, Q, and the international sunspot index Ri observed in the previous cycle is again confirmed. Finally, it is shown that the quality of sunspot activity of Cycle 22 is different from that of the previous cycle. (5pp)
Observing with a Browning prominence spectroscope ... R. A. Marriott
During the past few years I have attempted to observe solar prominences with two classic instruments. Some satisfying results have been obtained, but the prominences themselves have proved elusive. (1 p)
(Copies of any of these articles may be ordered from the BAA office.)
Letters
- SOHO - some corrections ... D. M. Simpson
- National Astronomy Week and the Campaign for Dark Skies ... Nigel Henbest
- Telescope limiting magnitudes and the exit pupil ... Richard Plasencia
- Early photography ... H. J. P. Arnold
- Mallard's record ... John Farquharson
Read the letters here
Reviews
The Hatfield Photographic Lunar Atlas by Jeremy Cook (Ed.) Springer-Verlag, 1999. ISBN 1-85233-018-X. Pp 122, £26.00 (hbk). (Price to BAA members: £19.00)
reviewed by Keith W. Abineri
- The New Solar System (4th edition) by J. Kelly Beatty, Carolyn Collins Petersen & Andrew Chaikin (Eds.) Cambridge University Press/Sky Publishing, 1999. ISBN 0-521-64183-7 (hbk), 0-521-64587-5 (pbk). Pp viii + 421, £40.00/£24.95.
reviewed by Richard McKim
- The Cambridge Concise History of Astronomy by Michael Hoskin (Ed.) Cambridge University Press, 1999. ISBN 0-521-57291-6 (hbk), 0-521-57600-8 (pbk). Pp xiv + 362, £45.00/£16.95.
reviewed by Jon Reynolds
The Victorian Amateur Astronomer: Independent Astronomical Research in Britain, 1820-1920 by Allan Chapman John Wiley/Praxis Publishing, 1998. ISBN 0-471-96257-0. Pp xxii + 428, £40.00 (hbk).
reviewed by Peter Hingley
- New Astronomer by Carole Stott Dorling Kindersley, 1999. ISBN 0-751-30666-5. Pp 144, £16.99 (hbk).
reviewed by Chris Lintott
- Discovering the Solar System by Barrie W. Jones John Wiley & Sons, 1999. ISBN 0-471-98243-1 (hbk), 0-471-98648-8 (pbk). Pp xvi + 416, £80.00/£19.99.
reviewed by Graham Young
Meeting reports
- Ordinary Meeting, 1999 February 27
Observers' Forum
- Spectra of the supernova SN1999by
- Conjunction of Venus and Jupiter, 1999 February 23
- Asteroid 6411 TAMAGA
- Supernova 1999cl in NGC 4501 (M88)
- Tennant Creek, Australia, 16.02.1999:
Annular eclipse of the Sun
BAA Update
- Obituary: Gunter Archenhold, 1904-1999
- Meeting of the Deep Sky Section, 1999 March 6
The Horsehead Nebula (part IC434). 305mm SCT at f6.3 with ST-7 CCD. 2hrs 30m exposure (18×10 mins) on 1999 January 11, mid-point 23.20 UT. Robert Dalby.
A copy of this or any other recent issue of the Journal may be ordered from the BAA office.
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