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Remarkably, the five largest recorded sunspot groups all occurred during a period of just over five years, from 1946 February to 1951 May, during Solar Cycle 18. These are the only groups known with areas greater than 4,500 millionths of the Sun’s visible hemisphere. This paper examines the white-light activity of the groups.

The recent so-called ‘Great Conjunction’ of Jupiter and Saturn, in 2020 December, was the latest in a series of conjunctions of the two planets that occur, on average, every 19.67 years. Although events between Jupiter and Saturn are visually not the most spectacular of conjunctions, they are of great historical interest due to the triple conjunction that occurred around the time of the Nativity, which authors such as Hughes (1976) have associated with the Star of Bethlehem. A total of 309 Jupiter–Saturn conjunctions are found between 1000 BC and AD 4000, which include 84 grouped in 28 triple conjunctions. The 2020 conjunction is found to be in the top five percent of closest approaches of the two planets over five millennia. The closest conjunctions show a strong preference for occurring in Cancer in July/August, or Capricornus in December.