1675 in science

Astronomy

• March 4 – John Flamsteed appointed as "astronomical observator", in effect, the first Astronomer Royal of England.
• Giovanni Cassini discovers Saturn's Cassini Division.

  Exploration

• The Antarctic Convergence is first crossed by Anthony de la Roché, who lands on South Georgia.

  Mathematics

• November 11 – German polymath Gottfried Leibniz uses infinitesimal calculus for the first time to find the area under the graph of the function y=f.

  Births

• February 28 – Guillaume Delisle, French cartographer

  Deaths

• October – James Gregory, Scottish mathematician and astronomer
• October 27 – Gilles de Roberval, French mathematician
• November 11 – Thomas Willis, English physician
• approx. date – John Jonston, Polish naturalist and physician