Pluto's Two Small Moons Christened Nix and Hydra

http://www.jhuapl.edu/newscenter/pre...006/060622.asp

For Immediate Release
June 22, 2006

Media Contacts

Michael Buckley (The Johns Hopkins University Applied Physics
Laboratory)
Phone: (240) 228-7536


Maria Martinez (Southwest Research Institute)
Phone: (210) 522-3305


Pluto's Two Small Moons Christened Nix and Hydra

The names Nix and Hydra have been approved for the two small satellites
of Pluto discovered in May 2005. The International Astronomical Union
(IAU), the internationally recognized authority for assigning
designations to celestial bodies, approved the names this week.

A team of researchers from Southwest Research Institute (SwRI) in
Boulder, Colo., the Johns Hopkins University Applied Physics Laboratory
(APL) in Laurel, Md., the Space Telescope Science Institute in
Baltimore
and Lowell Observatory in Flagstaff, Ariz., used Hubble Space Telescope
images to make the discovery in support of NASA's New Horizons mission
to Pluto and the Kuiper Belt beyond.

"We're very pleased with the decision of the IAU," says co-leader of
the
discovery team, Dr. Alan Stern, executive director of the SwRI Space
Science and Engineering Division and principal investigator of the New
Horizons mission. "You're going to be hearing a lot more about Nix and
Hydra in coming years - astronomers are already applying for telescope
time to study their orbits and physical properties. And when New
Horizons flies by Pluto in the summer of 2015, each will be mapped in
detail."

"Pluto doesn't reveal its moons easily," adds discovery team co-leader
and New Horizons Project Scientist Dr. Hal Weaver, of APL. "It took 48
years after the discovery of Pluto to find Charon and another 27 years
to find Nix and Hydra. Perhaps we won't have to wait as long for the
next discovery because the New Horizons spacecraft will be making a
rendezvous with Pluto in nine years and will be searching for other
small satellites."

Nix and Hydra, roughly 5,000 times fainter than Pluto itself, are about
two to three times as far from Pluto as its large moon, Charon, which
was discovered in 1978. The nine-member discovery team selected the
name
Nyx for S/2005 P 2, the inner small satellite, and the name Hydra for
S/2005 P 1, the outer small satellite. Because asteroid 3908 already
bears the Greek name Nyx, the IAU changed Nyx to its Egyptian
equivalent, Nix.

In mythology, Nix is the goddess of darkness and night, befitting a
satellite orbiting distant Pluto, the god of the underworld. Nix is
also
the mother of Charon, relevant to the giant impact believed to have
created Pluto's three satellites, indicating Charon was borne of the
material from which Nix formed. Hydra is the terrifying monster with
the
body of a serpent and nine heads, befitting the outermost moon of
Pluto,
the ninth planet in the solar system.

In addition, just as Pluto's name begins with the letters "P" and "L"
to
honor Percival Lowell, who motivated the search that led to its
discovery, Nix and Hydra honor the search for new satellites and the
New
Horizons mission to Pluto by starting with the letters "N" and "H." The
first letter of Hydra also honors the Hubble Space Telescope that was
used to detect the satellites.

Editors: Images to accompany this story are available at
http://www.swri.org/press/2006/nixhydra.htm and
http://pluto.jhuapl.edu


The Applied Physics Laboratory (APL) is a not for profit laboratory and
division of The Johns Hopkins University. APL conducts research and
development primarily for national security and for nondefense projects
of national and global significance. APL is located midway between
Baltimore and Washington, D.C., in Laurel, Md. For information, visit
www.jhuapl.edu .

SwRI is an independent, nonprofit, applied research and development
organization based in San Antonio, Tx., with more than 3,000 employees
and an annual research volume of more than $435 million. For more
information, visit www.swri.org .