On the evening of July 4, 1997, Jacob Matijevic (MATH ?69) waited along with the rest of the
world for the Mars rover called Sojourner to exit the Pathfinder lander and begin its
exploration of the red planet. This new era of U.S. space exploration was, for Matijevic, not
only an historic event, but also a critical moment in his career?a culmination of decades of
work and study. Matijevic remembers, ?It was a hectic two days of commanding the rover to
drive down Pathfinder?s ramp. By approximately midnight PDT on July 5, we received confirming
images that the rover was on Mars.? It had been a long ride, but Matijevic and Sojourner had
finally arrived.
?That was one of the happiest days of my life,? says Matijevic. ?It was a fitting end to
nearly five years of struggle to develop, test, and operate this new space system and a great
reward for the efforts of a team of dedicated engineers.?
Matijevic had become intrigued with the National Aeronautics and Space Administration (NASA)
space program?specifically the Voyager missions?while teaching mathematics at the University
of Southern California. Twin Voyagers 1 and 2, which launched in 1977, began an extensive tour
of the outer solar system by visiting Jupiter and Saturn before being propelled further. Still
sending signals back to Earth, they remain the farthest human-created objects to travel from
Earth and are on target to be the first spacecraft to leave the confines of our
heliosphere—an immense magnetic bubble containing our solar system, solar wind, and the
entire solar magnetic field. Matijevic followed Voyager?s discoveries closely, and in 1981 his
interest led him to NASA?s Jet Propulsion Laboratories (JPL), where he currently works in
operations as the Mars Exploration Rover Engineering Team chief.
Over the course of its existence, NASA has pursued new ways to increase the level of detail
gleaned from its planetary missions. The rover has extended the capacity of knowledge gained
from unmanned explorations. ?Rover? is a general term used to describe a thinking robot on
wheels with cameras that serve as its eyes. They travel inside landers?spacecraft that land
on the surface of another planet and are capable of collecting data, but that remain
stationary after landing. Rovers are programmed to run on autopilot and to react to unexpected
activity or planetary terrain. Information obtained by the rover is transmitted to the lander,
which stores and sends messages in between the rover and a NASA operator.
Matijevic says that while design concepts for rovers can be prototyped relatively
easily, it is only through rigid testing of these prototypes that engineers are
able to identify problems prior to implementation.
Jacob Matijevic (MATH '69) is developing the rovers that are giving us a new outlook on Mars.
|
|
A new journey: The Mars Pathfinder launches from Cape Canaveral Air Force Station in Florida on December 4, 1996
Photo courtesy NASA/JPL
|
| |
The Robot Hall of Fame
Almost a decade after its historic trip on the surface of Mars, Sojourner received
national recognition, along with three other robots, when they were all welcomed
into the Robot Hall of Fame. At Carnegie Hall on November 10, 2003, the First
Annual Induction Ceremony honored the Mars Pathfinder Sojourner Rover; the first
industrial robot, Unimate, developed in 1961, which worked with heated die-casting
machines on the assembly line at a General Motors plant; and two movie stars:
R2-D2 of Star Wars and HAL 9000, a central character in the Stanley Kubrick and
Arthur C. Clarke classic, 2001: A Space Odyssey.
|
| |
A Hole in One
Sojourner began its journey on Pathfinder seven months prior to its Mars
landing?traveling 119 million miles from Earth to its destiny. Moments before
reaching the surface, Pathfinder released its air bags in preparation for impact.
Around NASA, it has been said that the accomplishment of landing the Pathfinder
was like playing a par-four hole of golf?teeing off in California and aiming for a
four-inch, moving hole in Texas. According to the space mission log, the rover?s
primary goals were scheduled to occur within the first seven ?Martian days? and
all within about 30 feet of the lander. The extended mission included additional
analyses of nearby rock and soil and more tests of the rover?s capabilities.
|
| |
?Testing the capability of these vehicles to engage and then drive over obstacles
illustrates the geometric and dynamic limitations of the rover?s design,? he says.
?When possible, I like to include testing in a variety of terrains. There are many
situations presented to a vehicle in these tests that cannot be fully replicated
in a sandbox.?
Matijevic began working with robotics at JPL following the missions of NASA?s
Viking 1 and 2, which were the first successful landers to study Mars, in 1976?82.
After years of working on advanced mission concepts and technology development,
Matijevic joined the first flight demonstrator project and helped to create Sojourner.
Sojourner weighed only 23 pounds and explored about 750 square feet of Martian surface,
collecting 16,500 images from the lander?s camera. Today, Sojourner is still on the
surface of Mars waiting to be retrieved. Opportunity and Spirit followed, deployed in
January 2004. The rovers continue to send back exciting new details about Mars; as
of press date, Spirit had driven 3.07 miles and Opportunity 3.65 miles.
| |
In August 2005, NASA launched its most recent exploratory effort, the Mars
Reconnaissance Orbiter. The craft is on schedule to arrive in the Martian orbit
in March 2006, when it will use cameras to take extreme close-up photography of
the Martian surface, carry a sounder to find subsurface water, and look for safe
and scientifically worthy sites for future rover exploration.
With new glimpses of Mars and prospective missions to the planet shaping his
day-to-day life, Matijevic sees the galaxy through a lens into which the rest of
us could only hope to view. Still, he says, one discovery would trump them all:
?Hopefully these future missions will discover evidence that can determine
whether there had been past life on Mars. That?s the one space exploration
achievement I?d like to see in my lifetime.?
External Links:
JPL?s latest Mars rover findings
|
|
