#e <t>theory<d>1595<au>Kepler<n>nested Platonic solids<info>Kepler thought the distances of the planets from the sun could be explained by nesting the six known planets' spheres between the five Platonic solids.
#e <t>meeting<d>1600 Feb 4<n>Kepler and Brahe meet<c>Prague
#p <nat>English<o>astronomer<n>Sir John Herschel<b>1792<d>1871<fa>William Herschel
#e <t>obs<n>Uranus<d>1781 Mar 13<au>William Herschel
// 19th century
#e <t>obs<n>asteroid 1 Ceres<d>1801 Jan 1<info>the largest and first discovered asteroid<info>discovered by G. Piazzi
#e <t>obs<n>asteroid 2 Pallas<d>1802 Mar<info>the 2nd largest asteroid and 2nd asteroid discovered<info>discovered by Heinrich Olbers
#e <t>obs<n>asteroid 3 Juno<d>1804<info>the 3rd asteroid discovered<info>discovered by K. Harding
#e <t>obs<n>asteroid 4 Vesta<d>1845<info>the 3rd largest asteroid<info>Vesta appears to have a basaltic crust overlying an olivine mantle.
#e <t>obs<n>asteroid 5<d>1845<info>discovered by Karl Hencke
#e <t>obs<n>Neptune<d>1846 Sep 23
#e <t>obs<d>1877<n>Phobos and Deimos<c>U.S.<info>Asaph Hall, of U.S. Naval Observatory, discovers Mars' two moons.
// 20th century
#e <t>obs<n>Pluto<d>1930 Feb 18<info>by Clyde Tombaugh
#e <t>obs<n>Dactyl, satellite of asteroid 243 Ida<d>1993 Aug 28<info>imaged by Galileo probe
// Hubble
#p <nat>American<o>astronomer<n>Edwin Hubble<b>1889 Nov 20<d>1953 Sep 28<c>Chicago<mov>1920(2)<c>California
#e <t>obs<d>1923<n>existence of galaxies proven<c>Mount Wilson<au>Hubble<info>Hubble settled a long debate by demonstrating that the Andromeda "nebula" was actually a galaxy outside our own Milky Way and that many other such galaxies exist.
#e <t>theory<d>1925<n>classification of galaxies<au>Hubble<info>Hubble devised a classification scheme for the structure of galaxies that is still in use today in modified form.
#e <t>theory<d>1929<n>Hubble's law<au>Hubble<info>Hubble's law states that the more distant a galaxy is, the faster it is receding from us. The fundamental cosmological quantity known as Hubble's constant is derived from this law.