'Examples of Rapid Formations', 31 July 1865.

'Examples of Rapid Formations', 31 July 1865.
3 3 c m
actual image size: 32cm x 25cm


Illustration taken from 'Le Soleil' (Paris, 1875) by Secchi, showing a sunspot that had first appeared on 30th July 1865, and by the following day (when this drawing was made) had completely changed form. 'In 24 hours, the dimensions were considerably modified; the length had almost doubled: it was 147 seconds. During the following days the mass which separated the four openings transformed almost into a penumbra on which were dispersed luminous grains.' Secchi was a pioneer of solar astronomy in the 19th century, but although his theories were influential at the time, some of them, including his views on sunspots, are considered obsolete today. Sunspots are relatively cool areas on the Sun's surface, the photosphere.

Image Details

Image Ref.

© Science Museum / Science & Society Picture Library

buy a print

Select size
Select finish
How many prints?

buy a framed print

buy a canvas

buy a framed canvas