“I resolved to attempt the completion of a survey of the whole surface of the heavens, and for this purpose to transport into the other hemisphere the same instrument which had been employed in this, so as to give a unity to the results of both portions of the survey and to render them comparable with each other.”

JOHN HERSCHEL's DIARIES during his 19th century stay at the Cape give a fascinating insight into the life of this active observer (see the John Herschel-Cape of Good Hope page for introductory remarks). During his visit, he worked closely with Thomas Maclear, Astronomer at the Royal Observatory at the Cape of Good Hope.

I have gone through three works directly related to this period: Herschel's own "Results of Cape Observations", and the diary extracts published by Warner & Warner (1984) and Evans et al (1969). From these I have collected the following lists of interesting or otherwise remarkable objects:

1. Milky Way Clusters Several entries in h's catalogue refers to large patches of the milky way; these are:

"The principal object kept in view during the progress of my southern sweeps was the discovery of new nebulae. The detection and measurement of double stars was regarded as of subordinate interest, and allowed to interfere as little as possible with the former enquiry. To have executed a regular review of the southern heavens with the twenty-feet reflector for the purpose of detecting close double stars would have required at least two additional years."

2. Interesting comments by h

Chapman (1993) notes that Herschel’s 20-foot telescope is “probably the only single instrument to be used by the same observer to complete a review of both hemispheres.”

3. Observing at the limit: Challenging objects from the Cape Observations

References

Warner, B & Warner, N (1984) Maclear & Herschel: Letters & diaries at the Cape of Good Hope 1834-1838. AA Balkema, Cape Town. ISBN 0-86961-145-3

Evans, D. S., Deeming, T. J., Evans, B. H. & Goldfarb, S. (1969) Herschel at the Cape. Diaries and correspondence of Sir John Herschel 1834-1838. AA Balkema, Cape Town. ISBN 292-78387-6.