In 2003, NASA plans to launch a relative of the now-famous 1997 Mars Pathfinder rover. Using drop, bounce and roll technology, this larger cousin is expected to reach the surface of the red planet in January 2004 and begin the longest journey of scientific exploration ever undertaken across the surface of that alien world.
Dr. Edward Weiler, associate administrator of the Office of Space Science, NASA Headquarters, Washington, DC., announced today that the Mars rover was his choice from two mission options which had been under study since March.
"Today I am announcing that we have selected the Mars Exploration Program Rover rather than the orbiter option, which was an extremely difficult decision to make," said Weiler. "At the same time, we want to look into what could be an amazing opportunity, as well as a challenge, by sending two such rovers to two very different locations on Mars in 2003 rather than just one."
"We are evaluating the implications of a two-rover option," Weiler added. "I intend to make a decision in the next few weeks so that, if the decision is to proceed with two rovers, we can meet the development schedule for a 2003 launch."
With far greater mobility and scientific capability than the1997 Mars Pathfinder Sojourner rover, this new robotic explorer will be able to trek up to100 meters (110 yards) across the surface each Martian day, which is 24 hours, 37 minutes. The Mars rover will carry a sophisticated set of instruments that will allow it to search for evidence of liquid water that may have been present in the planet's past, as well as study the geologic building blocks on the surface.
"This mission will give us the first ever robot field geologist on Mars. It not only has the potential for breakthrough scientific discoveries, but also gives us necessary experience in full-scale surface science operations which will benefit all future missions," said Scott Hubbard, Mars program director at NASA Headquarters. "A landed mission in 2003 also allows us to take advantage of a very favorable alignment between Earth and Mars."
After launch on top a Delta II rocket, and a cruise of seven and a half months, the spacecraft would enter the Martian atmosphere January 20, 2004. In a landing similar to that of the Pathfinder spacecraft, a parachute will deploy to slow the spacecraft down, and airbags will inflate to cushion the landing. Upon reaching the surface the spacecraft will bounce about a dozen times and could roll as far as about one kilometer (a half mile). When it comes to a stop, the airbags will deflate and retract, and the petals will open, bringing the lander to an upright position and revealing the rover.
Where the Pathfinder mission consisted of a lander, with science instruments and camera, as well as the small Sojourner rover, the Mars 2003 mission features a design that is dramatically different. This new spacecraft will consist entirely of the large, long-range rover, which comes to the surface inside a Pathfinder landing system, making it essentially a mobile scientific lander.
Immediately after touchdown, the rover is expected to give us a virtual tour of the landing site by sending back a high- resolution 360-degree, panoramic color and infrared image. It will then leave the petal structure behind, driving off as scientists command the vehicle to go to rock and soil targets of interest.
This rover will be able to travel almost as far in one Martian day as the Sojourner rover did over its entire lifetime. Rocks and soils will be analyzed with a set of five instruments. A special tool called the "RAT," or rock abrasion tool, will also be used to expose fresh rock surfaces for study.
The rover will weigh about nearly 150 kilograms (about 300 pounds) and has a range of up to about 100 meters (110 yards) per sol, or Martian day. Surface operations will last for at least 90 sols, extending to late April 2004, but could continue longer, depending on the health of the rover.
"By studying a diverse array of Martian materials, including the interiors of rocks, the instruments aboard the rover will reveal the secrets of past Martian environments, possibly providing new perspectives on where to focus the quest for signs of past life," said Dr. Jim Garvin, Mars program scientist at NASA Headquarters. "Furthermore, the rover offers never-before- possible opportunities for discoveries about the Martian surface at scales ranging from microscopic to that of gigantic boulders. This is a key stepping stone to the future of our Mars exploration program."
One aspect of the Mars rover's mission is to determine history of climate and water at a site or sites on Mars where conditions may once have been warmer and wetter and thus potentially favorable to life as we know it here on Earth.
The exact landing site has not yet been chosen, but is likely to be a location such as a former lakebed or channel deposit -- a place where scientists believe there was once water. A site will be selected on the basis of intensive study of orbital data collected by the Mars Global Surveyor spacecraft, as well as the Mars 2001 orbiter and other missions.
The alternative mission, which had been under consideration for the 2003 opportunity, was a Mars scientific orbiter, which featured a camera capable of imaging objects as small as about 60 centimeters (two feet) across, an imaging spectrometer designed to search for mineralogical evidence of the role of ancient water in Martian history, and other science objectives.
Teams at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and Lockheed Martin Astronautics, Denver, Colo., conducted separate, intensive, two-month studies of the missions.
"Both teams did an absolutely superb job in preparing these proposals in a very compressed time frame," said Dr. Weiler. "They both deserve a lot of credit for what they were able to achieve."
"This project can be accommodated within the President's budget request for NASA, and we will spend the next few weeks refining our budget estimates and other requirements, plus the impacts and the consequences of sending two rovers to Mars instead of one," said Hubbard. "When we have fully addressed all of the issues, which may take several weeks, we will announce our final plans."
Images of the rover are available at: http://www.jpl.nasa.gov/pictures/solar/2003rover
News Media ContactMary Hardin, JPL, (818) 354-0344
Don Savage, NASA Headquarters, (202) 358-1727