1803 in science

The year 1803 in science and technology involved some significant events.

Astronomy

April 26 – A meteorite shower falls on L'Aigle in Normandy; Jean Baptiste Biot demonstrates that it is of extraterrestrial origin.

Publication of André Michaux's Flora Boreali-Americana in Paris, the first flora of North America.
University of Tartu Botanical Gardens established.

January 1 – William Henry's formulation of his law on the solubility of gases first published.
September 3 – English scientist John Dalton starts using symbols to represent the atoms of different chemical elements.
October 21 – John Dalton's atomic theory and list of molecular weights first made known, at a lecture in Manchester.
William Hyde Wollaston discovers the chemical element rhodium.
Smithson Tennant discovers the chemical elements iridium and osmium.
Cerium is discovered in Bastnäs by Jöns Jakob Berzelius and Wilhelm Hisinger, and independently in Germany by Martin Heinrich Klaproth.
Claude Louis Berthollet publishes in Paris.

June 9 – Matthew Flinders completes the first known circumnavigation of Australia.

Luke Howard publishes the basis of the modern classification and nomenclature of clouds.

Robert Ransome invents the self-sharpening chilled cast-iron ploughshare in Ipswich, England.
The first Fourdrinier continuous papermaking machine is installed in Hertfordshire, England.

January 4 – William Symington demonstrates his Charlotte Dundas, the "first practical steamboat", in Scotland.
July 26 – The Surrey Iron Railway, a wagonway between Wandsworth and Croydon, is opened, being the first public railway line in England.
Thomas Telford begins work on construction of the Caledonian Canal and improving roads in Scotland.