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Phoenix is a robotic spacecraft on a space exploration mission
on Mars under the Mars Scout Program. The scientists conducting
the mission are using instruments aboard the Phoenix lander to
search for environments suitable for microbial life on Mars, and
to research the history of water there.
The multi-agency program is headed by the Lunar and Planetary
Laboratory at the University of Arizona, under the direction of
NASA's Jet Propulsion Laboratory. The program is a partnership
of universities in the United States, Canada, Switzerland,
Denmark, Germany, the United Kingdom, NASA, the Canadian Space
Agency, the Finnish Meteorological Institute, Lockheed Martin
Space Systems, MacDonald Dettwiler & Associates (MDA) and other
aerospace companies. The operational funding for the mission
will extend through September 30, 2008.
Phoenix is the sixth successful landing on Mars (all of them
American), out of the twelve attempts that reached Mars. It is
the most recent spacecraft to land successfully on Mars. It is
also the first successful landing on a polar region of Mars.
The mission has two goals. One is to study the geologic history
of water, the key to unlocking the story of past climate change.
The second is evaluate past or potential planetary habitability
in the ice-soil boundary. Phoenix's instruments are suitable for
uncovering information on the geological and possibly biological
history of the Martian Arctic. Phoenix will be the first mission
to return data from either of the poles, and will contribute to
NASA's main strategy for Mars exploration, "Follow the water."
The primary mission is anticipated to last 90 sols (Martian
days) – just over 92 Earth days. Researchers are hoping that the
lander will survive into the Martian winter so that it can
witness polar ice developing at the spacecraft's exploration
area. As much as three feet of solid carbon dioxide ice could
appear in the area. Even if it does survive part way into the
winter, it is very unlikely that the lander will function
throughout the entire winter due to the intense cold. The
mission was chosen to be a fixed lander rather than a rover
because:
costs were reduced through reuse of earlier equipment;
the area of Mars where Phoenix is landing is thought to be
relatively uniform and thus traveling is of less value; and
the equipment weight that would be required to allow Phoenix to
travel can instead be dedicated to more and better scientific
instruments.
The 2003–2004 observations of methane gas on Mars were made
remotely by three teams working with separate data. If the
methane is truly present in the atmosphere of Mars, then
something must be producing it on the planet now, because the
gas is broken down by sunlight within 300 years, therefore the
importance to search for biological potential or habitability of
the Martian arctic's soils. Methane could also be the product of
a geochemical process or the result of volcanic or hydrothermal
activity. Other future missions may enable us to discover
whether life does indeed exist on Mars today.
While the proposal for Phoenix was being written, the Mars
Odyssey Orbiter used its gamma ray spectrometer and found the
distinctive signature of hydrogen on some Martian surface. The
only plausible source of hydrogen would be water in the form of
ice, frozen below the surface of Mars. The mission was funded on
the expectation that Phoenix would find water ice on the arctic
plains of Mars.[11] In August 2003 NASA selected the University
of Arizona "Phoenix" mission for launch in 2007. It was hoped
this would be the first in a new line of smaller, low-cost,
Scout missions in the agency's exploration of Mars program. The
selection was the result of an intense two-year competition with
proposals from other institutions. The $325 million NASA award
is more than six times larger than any other single research
grant in University of Arizona history.
Peter H. Smith of the University of Arizona Lunar and Planetary
Laboratory, as Principal Investigator, along with 24
Co-Investigators, were selected to lead the mission. The mission
was named after the Phoenix, a mythological bird that is
repeatedly reborn from its own ashes. The Phoenix spacecraft
contains several previously built components. The lander used
for the 2007–08 mission is the modified Mars Surveyor 2001
Lander (canceled in 2000), along with several of the instruments
from both that and the previous unsuccessful Mars Polar Lander
mission. Lockheed Martin, which built the lander, had kept the
nearly complete lander in an environmentally controlled clean
room from 2001 until the mission was funded by the NASA Scout
Program.
Phoenix is a partnership of universities, NASA centers, and the
aerospace industry. The science instruments and operations will
be a University of Arizona responsibility. NASA's Jet Propulsion
Laboratory in Pasadena, California, will manage the project and
provide mission design and control. Lockheed Martin Space
Systems, Denver, Colorado, built and tested the spacecraft. The
Canadian Space Agency will provide a meteorological station,
including an innovative Laser-based atmospheric sensor. The
co-investigator institutions include Malin Space Science Systems
(California), Max Planck Institute for Solar System Research
(Germany), NASA Ames Research Center (California), NASA Johnson
Space Center (Texas), MDA (Canada),Optech Incorporated (Canada),
SETI Institute, Texas A&M University, Tufts University,
University of Colorado, University of Copenhagen (Denmark),
University of Michigan, University of Neuchâtel (Switzerland),
University of Texas at Dallas, University of Washington,
Washington University in St. Louis, and York University
(Canada). Scientists from Imperial College London and Bristol
University have provided hardware for the mission and will be
part of the team operating the microscope station.
On June 2, 2005, following a critical review of the project's
planning progress and preliminary design, NASA approved the
mission to proceed as planned. The purpose of the review was to
confirm NASA's confidence in the mission. |
