MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
Contact: Franklin O'Donnell
FOR IMMEDIATE RELEASE
August 25, 1999
MARS POLAR LANDER TO ARRIVE ON SMOOTH, LAYERED TERRAIN
A strip of gentle, rolling plains near the Martian south
pole will serve as a welcome mat when NASA's Mars Polar Lander
touches down on the red planet on December 3.
NASA unveiled the landing site, a swath of terrain measuring
about 4,000 square kilometers (1,500 square miles), at a briefing
today at NASA Headquarters, Washington, DC.
"We looked for a site with slopes no steeper than 10
degrees," said Project Scientist Dr. Richard Zurek of NASA's Jet
Propulsion Laboratory, Pasadena, CA. "We chose a location with
some surface features but no cliffs or jagged peaks, because the
spacecraft will be able to land safely, yet we'll still
accomplish our science goals."
The landing site is located at 76 degrees south latitude and
195 degrees west longitude, near the northern edge of the layered
terrain in the vicinity of the Martian south pole.
"We believe this layered terrain is a record of climate
changes on Mars and, in a sense, digging into its surface will be
like reading tree rings or layers in an ice core," Zurek said.
"The presence of fine layers of dust and ice with varying
thickness will indicate changes in weather patterns and layer
formation that have been repeated in recent history. In
addition, we may find evidence of soil particles that formed in
ancient seas on Mars and were later blown into the polar
The landing will be targeted to the center of the site, a
rectangular area 200 kilometers (125 miles) long and 20
kilometers (12-1/2 miles) wide. The site was selected after the
project team studied pictures and altimeter information gathered
by NASA's Mars Global Surveyor, which is currently orbiting the
planet. The search was narrowed to four sites before the final
location was chosen. A backup landing site is located nearby, at
75 degrees south latitude and 180 degrees west longitude.
"For the next several weeks, we'll study newly transmitted
Mars Global Surveyor images," said Flight Team Manager Dr. Sam
Thurman at JPL. "If necessary, we can retarget for the backup
landing site as late as early October, when the flight team
begins preparations for landing."
The December 3 landing occurs toward the end of spring in
the Martian southern hemisphere. The sun will shine all day,
moving higher and lower in the sky but never dipping below the
horizon. This nonstop sunshine will power the lander's solar
panels for 90 days, until the Martian seasons change and the
lander's mission ends.
Launched on January 3, 1999, Mars Polar Lander will study
the soil and look for ice beneath the surface of the Martian
south pole. The lander also carries two Deep Space 2 microprobes
that will be deployed about five minutes before the spacecraft
enters the Martian atmosphere. The microprobes will smash into
the planet's surface and penetrate the soil to look for water
ice. The microprobes were developed under NASA's New Millennium
Images of the landing site and additional information about
Mars Polar Lander are available at the following web site:
Additional information about Deep Space 2 is available on
the web at:
JPL manages Mars Polar Lander and the New Millennium Program
for NASA's Office of Space Science, Washington, DC. JPL is a
division of the California Institute of Technology, Pasadena, CA.