19th February

On this day in 1672, Newton's first publication appeared as a letter in the Philosophical Transactions of the Royal Society. It dealt with his new theory of light, showing that a prism separates white light into its component colours. Huygens, Hooke, and others objected so strongly that he vowed not to publish again. Fortunately that vow was not kept.

On this day in 2013 Google released a Nicolaus Copernicus doodle.

The postage stamp of one of today's mathematicians at THIS LINK was issued in 1953.