Timeline of Solar system

Claudius Ptolemy

Period: 100 to 160

Nicolaus Copernicus

Period: Feb 19, 1473 to May 21, 1543

Galileo Galilei

Period: Feb 15, 1564 to Jan 8, 1642

Johannes Kepler

Period: Dec 27, 1571 to Nov 15, 1630

Edmond Halley

Period: Nov 8, 1656 to Jan 14, 1742

William Herschel

Period: Nov 15, 1738 to Aug 25, 1822

Discovery of the first four asteroids

Period: 1801 to 1807

Urbain Le Verrier

Period: Mar 11, 1811 to Sep 23, 1877

Clyde Tombaugh

Period: Feb 4, 1906 to Jan 17, 1997

Voyagers 1 and 2

Period: Aug 20, 1977 to Sep 5, 1977