The Partial Lunar Eclipse of May 11-12, 1892. By G. J. NEWBEGIN, F.R.A.S.
The night of May 11-12 turned out so exceptionally clear and
fine that (though in 16 ° of Declination) the moon soon became a steady object
in the telescope. With regard to the eclipse I decided to take a series of
photographs at about half-hour intervals, and to endeavour to secure a
permanent record of its several stages. The exposures were made at 9.20, 9.50,
10.30, 11, 11.30 p.m., 12 o'clock midnight, and 12.30 a.m. The periods of
exposure were varied, to allow for the decreasing illumination of the moon,
viz. :— 20s 20s 30s 40s 30s 20s 20s respectively.
The plates were the Ilford ordinary, developed by
hydroquinone. The instrument by which they were taken is a 9-inch Cooke
equatorial, aperture reduced to 2-inch for the whole series. The intervals
between the exposures were occupied in developing the plates.
Thorpe, Norwich, Nov. 11, 1892.
www.theramblingastronomer.co.uk
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