Sir Arthur Eddington
1919, 29 May
Total Solar Eclipse
[Royal Astronomical Society expedition to Principe]

Halftone
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Positive inverted image.
 
Original caption:
 
From the report of Sir Arthur Eddington on the expedition to verify Albert Einstein's prediction of the bending of light around the sun.
 
In Plate 1 is given a half-tone reproduction of one of the negatives taken with the 4-inch lens at Sobral. This shows the position of the stars, and, as far as possible in a reproduction of this kind, the character of the images, as there has been no retouching. A number of photographic prints have been made and applications for these from astronomers, who wish to assure themselves of the quality of the photographs, will be considered as as far as possible acceded to.
 
Source:
 
F.W. Dyson, A.S. Eddington, and C. Davidson, "A Determination of the Deflection of Light by the Sun's Gravitational Field, from Observations Made at the Total Eclipse of May 29, 1919", Philosophical Transactions of the Royal Society of London. Series A, Containing Papers of a Mathematical or Physical Character (1920): p.291-333, on p.332.
 
Additional note:
 
This image was of immense significance as it was an essential piece of the proof that light was effected by gravity which was postulated in Albert Einstein's theory of general relativity.
 
The significance of this event was portrayed, not entirely accurately, in the British drama Einstein and Eddington produced by Company Pictures and the BBC, in association with HBO. It was first broadcast on BBC Two on 22 November 2008.
 
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