A NASA robotic explorer equipped to dig up and analyze icy soil
on Mars sits atop a 13-story tall stack of rocket engines prepared
for liftoff before sunup on Saturday.
A Delta II launch vehicle will carry the Phoenix Mars Lander
into Earth orbit and, about 90 minutes later, give it the push
needed to send it to Mars. A three-week period when planetary
positions are favorable for this launch begins with an opportunity
at 5:26:34 a.m. EDT on Aug. 4. A second opportunity the same day,
if needed, will come at 6:02:59 a.m. EDT.
"We have worked for four years to get to this point, so we are
all very excited," said Barry Goldstein, Phoenix project manager at
NASA's Jet Propulsion Laboratory, Pasadena. "Our attention after
launch will be focused on flying the spacecraft to our selected
landing site, preparing for surface operations, and continuing our
relentless examination and testing for the all-important descent
and landing on May 25 of next year."
Phoenix will travel 422 million miles in an outward arc from
Earth to Mars. It will determine whether icy soil on far northern
Mars has conditions that have ever been suitable for life.
Studies of potential landing sites by spacecraft orbiting Mars
led NASA to approve a site at 68.35 degrees north latitude -- the
equivalent of northern Alaska -- and 233.0 degrees east
longitude.
"Phoenix investigates the recent Odyssey discovery of
near-surface ice in the northern plains on Mars," said Phoenix
Principal Investigator Peter Smith of the University of Arizona,
Tucson. "Our instruments are specially designed to find evidence
for periodic melting of the ice and to assess whether this large
region represents a habitable environment for Martian
microbes."
The Phoenix mission was proposed in 2002 by an international
team led by Smith. Twenty-four other teams also submitted proposals
to be the first Mars Scout mission. NASA chose Phoenix in 2003.
Phoenix uses a lander structure built for the 2001 Mars Surveyor
mission, which was scaled down before launch to an orbiter-only
mission.
"The spacecraft system and software development matured early in
the program. This enabled us to thoroughly test a stable lander
design over the entire integration and test schedule period," said
Ed Sedivy, spacecraft program manager for Lockheed Martin Space
Systems.
The Phoenix mission is led by Smith, with project management at
the JPL and development partnership at Lockheed Martin Space
Systems in Denver. The NASA Launch Services Program at Kennedy
Space Center and the United Launch Alliance are responsible for the
Delta II launch service. International contributions are provided
by the Canadian Space Agency; the University of Neuchatel,
Switzerland; the University of Copenhagen, Denmark; the Max Planck
Institute, Germany; and the Finnish Meteorological Institute. JPL
is a division of the California Institute of Technology in
Pasadena.