Introducing the Comet Observation database (COBS)

The Comet Observation database (COBS) is a unique service that enables comet observers to submit, display and analyse cometary data in a single location. The service is available to comet observers worldwide and currently represents one of the largest databases of comet observations available (containing more than 235,000 observations at 2018 August). Data stored in the COBS database is freely available to everyone and can be analysed within the COBS online analysis website or exported and further used in other analysis software and publications. Members of the British Astronomical Association (BAA) are encouraged to submit their ICQ-formatted observations to COBS in addition to the Comet Section.

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Saturn in the 2008/2009 apparition: Part II

Part I of this report described the observations of Saturn made by Saturn Section members during the 2008/2009 apparition. Part II presents observations of a number of satellite and shadow transits and Titan eclipses that occurred during the apparition.

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New measurements and analysis of the β Cephei star V909 Cassiopeiae

V909 Cas is a little-studied example of a β (Beta) Cep pulsating variable star, located in the OB association Cas OB8 in the Perseus spiral arm of the Milky Way. Photometric observations in 2016-’17 provided thirty new times of pulsation extrema and enabled its mean pulsation period to be determined as 0.2067798(1)d. From spectroscopic observations we determined its interstellar extinction and absolute magnitude and luminosity, and located it with other β Cep stars in the OB instability region of the H-R diagram.

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The 2012 solar transit of Venus

Results from the 2012 June solar transit of Venus are illustrated and discussed, and make an interesting comparison with our recent report on the 2016 transit of Mercury. As in previous years, observers were able to time the contacts, to see the ‘Black Drop’ effect (caused by inadequate resolution, but often enhanced by turbulence) and to record the ring of light around the unilluminated limb at both ingress and egress. This will be the last transit of Venus until 2117 Dec 11, unless we include the event of 2020 Jun 3, when the planet will be silhouetted against the solar corona.

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