Timeline
1906 Percival Lowell completes the construction of his observatory at Flagstaff, USA and begins to search for a planet beyond Neptune, which he labels Planet X.
19th March 1915 Lowell takes the first astronomical photographs on which Pluto appears, but does not spot the planet's tiny dot on them
18th February 1930 Pluto discovered by Clyde Tombaugh at Lowell Observatory, USA
September 1930 First appearance of Pluto (though not named as such) in fiction: H.P. Lovecraft's "The Whisperer in Darkness" (not published until August 1931)
Spring 1931 First story set on Pluto : "In Plutonian Depths" by Stanford A. Coblentz.
22nd June 1978 James Christy discovers that Pluto has a moon, soon named Charon.
21st January 1979 Jan 21 Pluto crosses the orbit of Neptune, making the latter the outermost planet
9th November 2004 First film set (partly) on Pluto: "Space Odyssey" (BBC)2004
15th May, 2005 Two further Plutonian moons found, using the Hubble Space Telescope. They are later named Nix and Hydra.
19th January 2006 The New Horizons probe is launched.
24th August 2006 The International Astronomical Union votes on a definition of "planet" which means that Pluto does not qualify. Together with Ceres and Eris, it is given the new classification of "dwarf planet." Several other such dwarf planets have since been found.
20th July 2011 A fourth moon is found by the HST and named Kerberos.
7th July 2012 A fifth moon, Styx is discovered.
14th July 2015 Closest approach of New Horizons to Pluto
observatory at Flagstaff, USA and begins to search for a planet beyond Neptune, which he labels Planet X.
19th March 1915 Lowell takes the first astronomical photographs on which Pluto appears, but does not spot the planet's tiny dot on them
18th February 1930 Pluto discovered by Clyde Tombaugh at Lowell Observatory, USA
September 1930 First appearance of Pluto (though not as such) in fiction: H.P. Lovecraft's "The Whisperer in Darkness" (not published until August 1931)
Spring 1931 First story set on Pluto : "In Plutonian Depths" by Stanford A. Coblentz.
22nd June 1978 James Christy discovers that Pluto has a moon, soon named Charon.
21st January 1979 Jan 21 Pluto crosses the orbit of Neptune, making the latter the outermost planet
9th November 2004 First film set (partly) on Pluto: "Space Odyssey" (BBC)
15th May, 2005 Two further Plutonian moons found, using the Hubble Space Telescope. They are later named Nix and Hydra.
31st October 2005 Two further Plutonian moons found, by the Hubble Space Telescope.
19th January 2006 The New Horizons probe is launched.
24th August 2006 The International Astronomical Union votes on a definition of "planet" which means that Pluto does not qualify. Together with Ceres and Eris, it is given the new classification of "dwarf planet." Several other such dwarf planets have since been found.
20th July 2011 A fourth moon is found by the HST and named Kerberos.
7th July 2012 A fifth moon, Styx is discovered.
14th July 2015 Closest approach of New Horizons to Pluto
observatory at Flagstaff, USA and begins to search for a planet beyond Neptune, which he labels Planet X.
19th March 1915 Lowell takes the first astronomical photographs on which Pluto appears, but does not spot the planet's tiny dot on them
18th February 1930 Pluto discovered by Clyde Tombaugh at Lowell Observatory, USA
September 1930 First appearance of Pluto (though not as such) in fiction: H.P. Lovecraft's "The Whisperer in Darkness" (not published until August 1931)
Spring 1931 First story set on Pluto : "In Plutonian Depths" by Stanford A. Coblentz.
22nd June 1978 James Christy discovers that Pluto has a moon, soon named Charon.
21st January 1979 Jan 21 Pluto crosses the orbit of Neptune, making the latter the outermost planet
9th November 2004 First film set (partly) on Pluto: "Space Odyssey" (BBC)
15th May, 2005 Two further Plutonian moons found, using the Hubble Space Telescope. They are later named Nix and Hydra.
31st October 2005 Two further Plutonian moons found, by the Hubble Space Telescope.
19th January 2006 The New Horizons probe is launched.
24th August 2006 The International Astronomical Union votes on a definition of "planet" which means that Pluto does not qualify. Together with Ceres and Eris, it is given the new classification of "dwarf planet." Several other such dwarf planets have since been found.
20th July 2011 A fourth moon is found by the HST and named Kerberos.
7th July 2012 A fifth moon, Styx is discovered.
14th July 2015 Closest approach of New Horizons to Pluto