* Astronomy

On 6 March 1869, Dmitri Mendeleev presented the first periodic table to the Russian Chemical Society
http://astronomy.activeboard.com/t47720594/dmitri-ivanovich-mendeleev-1834-1907/

Leroy Gordon Cooper, Jr. (March 6, 1927 - October 4, 2004) was an one of the seven original astronauts in Project Mercury
http://en.wikipedia.org/wiki/Gordon_Cooper

Valentina Vladimirovna Tereshkova (born 6 March 1937) is a retired Soviet cosmonaut 
http://en.wikipedia.org/wiki/Valentina_Tereshkova

Patrick Pierre Roger Baudry (born March 6, 1946) is a former CNES astronaut.
http://en.wikipedia.org/wiki/Patrick_Baudry

Marie Alfred Cornu (March 6, 1841 - April 12, 1902) was a French physicist 
http://en.wikipedia.org/wiki/Marie_Alfred_Cornu

Michelangelo di Lodovico Buonarroti Simoni (6 March 1475 - 18 February 1564) was an Italian sculptor, painter, architect, poet, and engineer of the High Renaissance
http://en.wikipedia.org/wiki/Michelangelo

Joseph von Fraunhofer (6 March 1787 - 7 June 1826) was a German optician.
http://astronomy.activeboard.com/t48131946/joseph-von-fraunhofer-1787-1826/

Johann Georg Hagen (March 6, 1847 - September 5, 1930) was an Austrian Jesuit priest and astronomer.
http://en.wikipedia.org/wiki/Johann_Georg_Hagen

Madge Gertrude Adam (March 6, 1912 - August 25, 2001) was an English solar astronomer.
http://en.wikipedia.org/wiki/Madge_Adam

Carolyn C. Porco (born March 6, 1953) is an American planetary scientist known for her work in the exploration of the outer solar system.
http://en.wikipedia.org/wiki/Carolyn_Porco

Asteroid (246) Asporina was discovered by A. Borrelly on March 6, 1885
http://en.wikipedia.org/wiki/246_Asporina

Asteroid (727) Nipponia was originally discovered by Shin Hirayama in Tokyo on March 6, 1900. 
http://en.wikipedia.org/wiki/727_Nipponia

Hegemone also known as Jupiter XXXIX, is a natural satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003, and given the temporary designation S/2003 J 8.
http://en.wikipedia.org/wiki/Hegemone_(moon)

Helike, also known as Jupiter XLV, is a moon of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003, and given the temporary designation S/2003 J 6
http://en.wikipedia.org/wiki/Helike_(moon)

The Great Comet of 1843 passed closest to Earth on March 6, 1843
http://en.wikipedia.org/wiki/File:Great_Comet_of_1843.jpg

Comet 13P/Olbers was discovered by Heinrich Wilhelm Matthias Olbers (Bremen) on March 6, 1815. 
http://en.wikipedia.org/wiki/13P/Olbers

An Account Of A Surprising Meteor, Seen In The Air, March 6, 1716
http://books.google.co.uk/books?id=-i44AAAAMAAJ&pg=PA1#v=onepage&q&f=false