Seven days into surface activities on the Mars Pathfinder mission, all spacecraft systems and instruments are continuing to perform well. The rover remains in excellent health and appears to be driving a little bit faster when left to its own devices than when it receives instructions from Earth.
 

"Basically the rover overshot its target rock, Yogi, by a little bit last night," explained Dr. Justin Maki, of the University of Arizona, who is a member of the Imager for Mars Pathfinder (IMP) team. Maki showed a movie of Sojourner as it approached the large boulder and began to climb up its side with one wheel. In this type of dead reckoning, the rover performed just as it should have, which was to back off the rock once it knew the rock was in the way, then turned and moved away from the object. Although the rover travels about 1 centimeter per second (about 2 feet per minute), it appeared to be moving a little bit faster on its own.

July 10, 1997 (Sol 7)

Sojourner has made contact with the rock Yogi in this image, taken with the Imager for Mars Pathfinder (IMP) at 8:45 p.m. PDT on Sol 6. The rover's left rear wheel has driven up onto the Yogi's surface in an attempt to get as close as possible to the rock's surface. Sojourner will later use its Alpha Proton X-Ray Spectrometer (APXS) instrument to conduct a study of Yogi's chemical composition.

The science team targeted the left side of Yogi for alpha proton X-ray spectrometer study because it appears to be dark and free of Martian dust. However, that side turned out to be tricky for the rover because of the rock's uneven contours and the slight depression in the soil beneath the rock. The rover team will instruct Sojourner to attempt instrument placement again tonight. Multiple attempts to position the science instrument were anticipated, making this repeat attempt nothing out of the usual.

The latest pinpointing of the Mars Pathfinder Landing Site.

The navigation team also announced the Ares Vallis landing site coordinates today as 19.33 degrees north latitude, 33.55 degrees west longitude.

 Dr. Carol Stoker of NASA Ames Research Center showed some of the virtual reality products that her team is beginning to produce from the Pathfinder data during today's press briefing. Data from the lander camera's stereo images are overlain with terrain models to create the three-dimensional perspective, which can then be rotated in any direction on any plane on a computer screen. The 3-D perspective will be very useful to the science team in planning rover traverses and in analyzing data.

The "monster panorama" in stereo. (You'll need red/blue glasses for stereo viewing). It is broken into sections because of its large size. This frame is only a tile of a series covering 360 degrees.

Lander and Rover on Mars (748k)  Look at the lander and rover on a real estimate of the Mars Pathfinder landing site!

Dr. Julio Magalhaes, also of NASA Ames Research Center, a member of the atmospheric structure instrument/meteorology package (ASI/MET) on board the Pathfinder lander, reported that atmospheric temperatures  in the upper atmosphere of Mars are extremely cold. The science team has recorded temperatures at an altitude of 80 kilometers (50 miles) above the surface as minus 171 Celsius (minus 275 degrees Fahrenheit). In the lower atmosphere, between 60 km to 13 km (37 to 8 miles), the temperatures are warmer and very close to those recorded by the Viking landers of the mid-1970s.

The next scheduled press briefing will be held at 12:00 Noon Pacific Daylight Time on July 11 in JPL's von Karman Auditorium.

For more information, please visit our website at http://mpfwww.jpl.nasa.gov.