home Pluto is about1500 miles in diameter and takes 248
years to circle the Sun. Its day is about one Earth week long.
Charon revolves around Pluto in a little over 6 days.
(SFEC, 5/30/99, p.11)
If the Sun were a pumpkin one foot in diameter, Pluto would be
smaller than a strawberry seed nearly a mile away.
(SFEC, 4/30/00, Par p.9) 1916
Percival Lowell, American astronomer, died. He
believed that an unknown planet was affecting the orbit of Neptune,
which was discovered in 1930. The first two letters of Pluto
commemorate his name.
(Disc. Ch., 7/23/95)(SFEC, 5/30/99, Par p.13)
1930 Feb 18, Planet X (Pluto),
the ninth planet of our solar system, was discovered by Clyde
Tombaugh (1907-1997) at Lowell Observatory in Flagstaff, Ariz. It is
2.76 billion miles (5,888 million km.) from the sun at the closest
point of its orbit. Pluto was later designated a "dwarf planet."
(SFEC, 1/19/97, p.B6)(SFC, 10/23/99, p.B7)(AP,
1930 Mar 13, The Lowell
Observatory in Arizona announced Clyde Tombaugh’s Feb 18 discovery
of a new planet, later named Pluto.
(HN, 3/13/98)(NH, 6/03, p.20)
1930 May 1, Pluto was first
publicly announced as the name of a newly discovered
planet. Venetia Phair (11) had suggested the name to her
grandfather, librarian Falconer Madan, who relayed the suggestion to
his friend Herbert Hall Turner, professor of astronomy at Oxford.
Madan rewarded Phair (1919-2009) with a five-pound note. The same
purchasing power in 2009 would be about 230 pounds, or $350.
1978 Jun 22, James Christy,
while working at the United States Naval Observatory, discovered
that Pluto had a moon, which he named Charon.
(SFEC, 5/30/99, Par
1979 Jan 21, Neptune became the
outermost planet as Pluto moved closer due to their highly
1996 Mar 7, The Hubble Space
Telescope photographed the 1st surface photos of Pluto.
1996 The Pluto-Kuiper Express,
a mission to send a probe to Pluto, was approved.
(SFC, 9/22/00, p.A6)
2000 Sep, The Pluto-Kuiper
Express mission, scheduled to explore Pluto and its moon Charon in
2012, was delayed due to costs. A cheaper design was discussed for a
2020 exploration date.
(SFC, 9/22/00, p.A6)
2005 Oct 31, It was reported
that Pluto has three moons, not one, according to new images from
the Hubble Space Telescope suggest. The two new moons were named Nix
and Hydra. Pluto, discovered as the ninth planet in 1930, was
thought to be alone until its moon Charon was spotted in 1978. Two
more moons were discovered in 2011 and 2012.
(AP, 11/1/05)(Econ, 7/11/15, p.70)
2006 Jan 17, NASA postponed a
planned mission to Pluto. Scientists won't be able to receive data
on Pluto until at least July 2015, the earliest date the mission is
expected to arrive.
2006 Jan 19, NASA launched its
New Horizons spacecraft on a mission to Pluto following a 2-day
delay. Scientists won't be able to receive data on Pluto until at
least July 2015, the earliest date the mission is expected to
arrive. The spacecraft carried ashes of Clyde Tombaugh (1906-1997),
the man who discovered Pluto.
(SFC, 1/20/06, p.A5)(SFC, 7/13/15, p.A7)
2006 Jun 21, It was reported
that the pair of moons orbiting Pluto were officially christened Nix
and Hydra last week by the International Astronomical Union, which
is in charge of approving celestial names.
2006 Aug 24, Leading
astronomers meeting in Prague declared that Pluto is no longer a
planet under historic new guidelines that downsize the solar system
from nine planets to eight.
2011 Jul 20, NASA said that the
Hubble Space Telescope has found a 4th moon circling Pluto. It was
later named Kerberos.
2012 Jul 11, US astronomer Mark
Showalter of the SETI Institute said he has detected a 5th moon
around Pluto. Showalter used the Hubble Space Telescope and said the
new moon, named P-5, is about 6-15 miles across. The moon was later
(SFC, 7/12/12, p.C4)(Econ, 7/11/15, p.70)
2013 Jul 2, The Int’l.
Astronomical Union announced the names of Kerberos and Styx for two
moons of Pluto.
(SFC, 7/3/13, p.D1)
2015 Jul 14, The New Horizons
spacecraft flew to just 7,800 miles from Pluto to take the first
high-resolution images of the dwarf planet.
(SFC, 7/15/15, p.A6)