Wednesday 3 November 2021

Bright spot on dark side of the Moon seen with a Cooke


 At 7h.30m on the 9th inst, while waiting for the occultation of 130 Tauri, I was surprised to observe, a spot on the dark side of the Moon’s disc, nearly equal in brightness to a star of the 7th mag,; it was so conspicuous that it could not possible have been overlooked by the most careful; observer.

Unfortunately, I was unable to fix its position with accuracy; but after careful consideration I think its place was nearly, if not quite, identical with that of Aristarchus.

The outlines of the various ‘seas’ and of a few of the larger craters on the NE and SE quadrants were very plainly seen; Grimaldi, especially, was remarkable distinct.

I watched he spot from 7h 30m to 8h 30m; at about 8h 15m it became much fainter; and on returning to my observatory at about 9h I could scarcely perceive any trace of it.

Although I have observed very similar phenomena on former occasions, yet I have never before seen a spot on the dark side of the Moon with such remarkable clearness.

The definition on the evening of the 9th inst was bad, but the atmosphere was unusually clear.

Powers used: 75 and 115 on 4 inches aperture by Cooke.

T G E Elger

Bedford April 12th 1867

No comments:

Post a Comment