ONE MONTH UNTIL THE TRANSIT OF MERCURY: Mark your calendar. One month from today, the tiny black form of Mercury will cross the disk of the sun--a rare transit that happens only 13 times each century. Start planning now so you can witness this beautiful event on Nov. 11, 2019. Visibility maps and observing tips are featured on today's edition of Spaceweather.com .
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Above: A previous transit of Mercury photographed on May 9, 2016, by Paul Andrew of St. Margarets at Cliffe, Dover, UK. More images of that transit may be found here and here.
