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ABSTRACT A NEW STAR CATALOGUE FROM OBSERVATIONS WITH THE GREENWICH ALTAZIMUTH.—The present Greenwich altazimuth was erected in 1897, taking the place of Airy's smaller instrument which

had been in use for half a century. It was used for observing the moon in the first and last quarters of each lunation, at which periods meridian observations are untrustworthy. For the rest

of the time it was used in the meridian as a second transit circle. When Brown's new tables of the moon were introduced into the almanac in 1923 there was such an improvement in the

representation of all the short-period terms in its motion that it was considered that meridian observations of it would suffice for the future. The altazimuth was then placed in the Prime

Vertical for the observation of fundamental stars, and a catalogue of these, based on observations extending from June 1923 to January 1927 has just been issued; it contains all stars of

magnitude 5.4 and brighter, the declination of which lies between N. 11° 40′ and N. 50°, their number being 601. Observations were made in azimuth only; the declination, which is found with

greater accuracy than the right ascension, depends on the interval between the east and west transit of each star; refraction is not directly introduced, and the results form a useful check

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FAQs * Contact customer support RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Our Astronomical Column. _Nature_ 122, 378 (1928).

https://doi.org/10.1038/122378a0 Download citation * Issue Date: 08 September 1928 * DOI: https://doi.org/10.1038/122378a0 SHARE THIS ARTICLE Anyone you share the following link with will be

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