German mathematician, astronomer and astrologer (1571–1630) best known for his eponymous laws of planetary motion. Extremely rare ink signature, “Johannes Kepplar, Mathematicus,” on a light brown 5 x 3 slip, dated 1628 by Kepler, who also adds a two line notation along top edge, and a well-defined red wax seal next to signature. Mounted and framed with a woodcut engraving to an overall size of 10 x 14. In fine condition, with a couple small ink and pencil notations. The only Kepler autograph we have offered in over 30 years. Pre-certified John Reznikoff/PSA/DNA and RR Auction COA.
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