Abstract
MISTY or foggy conditions in Britain on Februaru 4 made it possible to see with the naked eye a big group of sunspots that had grown rapidly after February 1. Another factor which contributed to its ‘discovery' by many members of the general public was the favourable position of the spot group near the centre of the disk. At central meridian passage on February 5·4, the group passed within 2° of the centre of the disk, and its area was then greater than 2,000 millionths or 1/500 part of the sun‘s hemisphere. Although in size the present sunspot was only about half that of the four giant spots seen in 1946-47, it has attracted more general interest, because of the recent atmospheric conditions for its easy visibility, and also because of the earlier big spot group of comparable size a fortnight earlier, with the associated auroral display on January 24-25 (see Nature, February 5, p. 203). Observers of the setting sun, seen through the London mist on February 4, could also pick out with the unaided eye two other spots.
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Another Big Sunspot. Nature 163, 241 (1949). https://doi.org/10.1038/163241d0
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DOI: https://doi.org/10.1038/163241d0