Press Conference Day

Dr. Matthew Golombek, JPL Mars Pathfinder Project Scientist sol35l.gif The Sojourner rover is next to the rock "Wedge" in this image taken on Sol 35. From this position, the rover took an image of Wedge from its rear color camera (see sol35r.gif). The cylindrical instrument protruding from the rear of Sojourner is the Alpha Proton X-Ray Spectrometer (APXS), an instrument that measures the chemical composition of rocks and soils. The APXS was successfully deployed against Wedge on the night of Sol 37 (see sol37l.gif and sol37r.gif). sol35r.gif This image of the rock "Wedge" was taken from the Sojourner rover's rear color camera on Sol 37 (the position of the rover relative to Wedge is seen in sol35l.gif). The rock exhibits a rough texture consisting of small protrusions and pits. The rocks in the background comprise the "Rock Garden",where Sojourner visited after investigating Wedge.  sol37l.gif This image taken on Sol 37 shows the Sojourner rover backed next to the rock "Wedge." The Alpha Proton X-Ray Spectrometer (APXS), the bright object visible above the rear most wheel, is deployed on to the surface of Wedge. During the night of Sol 37 the APXS successfully measured the chemical composition of the rock. A close-up of Wedge and the APXS deployed on its surface is seen in sol37r.gif. sol37r.gif This image of the rock "Wedge" was taken from the Sojourner rover's rear color camera on Sol 37 (the position of the rover relative to Wedge is seen in sol37l.gif). The segmented rod visible in the middle of the frame is the deployment arm for the Alpha Proton X-Ray Spectrometer (APXS).The APXS, the bright, cylindrical object at the end of the arm, is positioned against Wedge and is designed to measure the rock's chemical composition. This was done successfully on the night of Sol 37. sol39l.gif This image of the Mars Pathfinder lander was taken from the Sojourner rover's left front camera on Sol 39. Deflated air bags are visible at the base of the spacecraft. The American flag and the letters "JPL" are seen on Pathfinder's white electronics housing. The mast for the Pathfinder camera extends upward from the top of the housing. The front rover ramp is perched on top of the air bags and is several feet above the ground. Because of this precarious position, Sojourner used the rear ramp to reach the surface on Sol 2. The large rock visible behind the air bags is "Yogi." sol41-S55.gif This image of the Sojourner rover was taken near the end of daytime operations on Sol 41. The right front wheel is parked on a small rock, perching the left front wheel above the surface. Behind the rover is the rock "Wedge," which was studied by Sojourner's Alpha Proton X-ray Spectrometer on the night of Sol 37. sol42-S55.gif This image of the Sojourner rover was taken near the end of daytime operations on Sol 42. The rover is between the rocks "Wedge" (left)and "Flute Top" (right). Other rocks visible include "Flat Top" (behind Flute Top) and those in the rock garden, at the top of the frame. The cylindrical object extending from the back end of Sojourner is the Alpha Proton X-Ray Spectrometer. sol42.gif This image of the rock "Flat Top" was taken from one of the Sojourner rover's front cameras on Sol 42. Pits on the edge of the rock and a fluted surface are clearly visible. The rocks in the left background comprise the Rock Garden. sol44l.gif This image taken on Sol 44 shows the Sojourner rover with its left front and middle wheels perched on the rock "Wedge." The rover's Alpha Proton X-ray Spectrometer is the cylindrical object extending from the back of the rover. sol47l.gif This image taken on Sol 47 shows the Sojourner rover with its left rear wheel perched on the rock "Wedge." The rover's Alpha Proton X-ray Spectrometer is the cylindrical object extending from the back of the rover. sol50_eod.gif This image taken near the end of daytime operations on Sol 50 shows the Sojourner rover between the rocks "Wedge" (foreground) and "Shark"(behind rover). The rover successfully deployed its Alpha Proton X-Ray Spectrometer on Shark on Sol 52. rover_movie_sol39.gif This movie shows the Sojourner rover backing off the rock "Wedge" on Sol 39. At the end of the film the rover bumps in to the rock "Hassock." rover_movie_sol52_S0050A.gif This movie shows the Sojourner rover positioning itself near the rock "Shark" on Sol 52. The rover's Alpha Proton X-Ray Spectrometer was successfully deployed on to Shark that evening. Sol52_eod.gif This image shows the Sojourner rover next to the rock "Shark"near the end of daytime operations on Sol 52. The rover's Alpha Proton X-ray Spectrometer is deployed against the rock rock_garden.jpg This image mosaic shows the "Rock Garden", the region of the Pathfinder landing site that the Sojourner rover started investigating on Sol 52. The Rock Garden is the assemblage of several large boulders in the middle left of the frame. The Twin Peaks are visible in the distance.

Dr. Tim Schofield, JPL Atmospheric Structure/Meteorology Package Team Leader   wthr_rpt_Schofield.jpg   TvsZ_Schofield.jpg   T(z).gif

Dr. Mark Lemmon, University of Arizona Mars Pathfinder Imaging Team 83621f.jpg On Sol 39 there were wispy blue clouds in the pre-dawn sky of Mars, as seen by the Imager for Mars Pathfinder. The color image was made by taking blue, green, and red images and then combining them into a single color image. The clouds appear to have a bluish side and a greenish side because they moved (in the wind from the northeast) between images. This picture was made an hour and twenty minutes before sunrise -- the sun is not shining directly on the water ice clouds, but they are illuminated by the dawn twilight. 83616f_th.jpg These clouds from Sol 15 have a new look. As water ice clouds cover the sky, the sky takes on a more bluish cast. This is because small particles (perhaps a tenth the size of the Martian dust, or one-thousandth the thickness of a human hair) are bright in blue light, but almost invisible in red light. Thus, scientists expect that the ice particles in the clouds are very small. The clouds were imaged by the Imager for Mars Pathfinder (IMP). sr39_32.jpg These are more wispy blue clouds from Sol 39 as seen by the Imager for Mars Pathfinder. The bright clouds near the bottom are about 10 degrees above the horizon. The clouds are believed to be at an altitude of 10 to 15 km, and are thought to be made of small water ice particles. The picture was taken about 40 minutes before sunrise. sr39_43.gif These are more wispy blue clouds from Sol 39 as seen by the Imager for Mars Pathfinder. The bright clouds near the bottom are about 30 degrees above the horizon. The clouds are believed to be at an altitude of 10 to 15 km, and are thought to be made of small water ice particles. The picture was taken about 35 minutes before sunrise ss24_0.jpg This is a close-up of the sunset on Sol 24. The red sky in the background and the blue around the Sun are approximately as they would appear to the human eye. The color of the Sun itself is not right -- the Sun was over exposed in each of the 3 color images that were used to make this picture.The true color of the Sun itself may be near white or slightly bluish sunset_new.jpg This image of the Martian sunset from Sol 24 shows much more color variation than had previously been seen. The blue color near the Sun is not caused by clouds of water ice, but by the Martian dust itself. The dust in the atmosphere absorbs blue light, giving the sky its red color, but it also scatters some of the blue light into the area just around the Sun because of its size. The blue color only becomes apparent near sunrise and sunset, when the light has to pass through the largest amount of dust.

Dr. Tom Economou, University of Chicago Co-Investigator, Alpha Proton X-ray Spectrometer Team  Will be Posted Next Week

Howard Eisen, JPL Principal Investigator, Soil Mechanics Technology Experiment Poptart.gif Source: Rover Front Right Camera Pop-tart, a small rock or indurated soil material was pushed out of the surrounding drift material by Sojourner's front left wheel during a soil mechanics experiment RF26110.gif Source: Rover Front Right Camera The Rover is located next to Pooh bear(rock at left) and Piglet (not seen)as it looks out toward Mermaid Dune. The soil textures differ from the foreground where the soil a poorly sorted mix of small rocks, fines and clods to the area a bit ahead of the rover where the surface is covered with a bright drift material.Soil experiments where the rover wheels dug in the soil revealed that the cloddy material exists underneath the drift. front_yogi.gif Source: IMP The Rover, while on its way to Yogi, performed several soil mechanics experiments. Piles of loose material churned up from the experiment are seen in front of and behind the Rover. Pop-tart is visible near the front right rover wheel. Shaggy_sol23.gif Source:IMP The IMP caught this image of the Rover as it was digging in the "compressible" material near Casper to determine the soil's mechanical properties.Shaggy is the large rock behind the Rover.

MARS PATHFINDER MISSION STATUS
28 August 1997, 8:00 a.m. PDT

We have completed another successful day of operations at the Sagan Memorial Station. Earth rise on Sol 54 occurred at 8:55 pm PDT Wednesday night and sunrise occured at 11:45 pm.

The lander continues to be in excellent health. The activities for today were to acquire more super pan imaging data and additional weather measurements. In addition we are performing a special test with the approaching Mars Global Surveyor spacecraft. This test involves near simultaneous tracking and will demonstrate the technique that will be used for the Mars Surveyor 98 mission.

The rover remains healthy with the exception of continued accelerometer and gyro noise problems. The plan for today was to turn slightly and place the APXS on the rock Half Dome. While performing the turn we tripped a potential hazard limit which terminated the activity. In this case it was due to one of the wheels riding up on the side of the rock and producing a larger than expected rover tilt angle . These limits are set very conservatively to ensure the the rover does not tip over . Engineers will look the rover engineering data and pictures taken by the lander camera to determine if it is safe relax these limits and continue to perform the turn tomorrow.

For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.

MARS PATHFINDER MISSION STATUS
27 August 1997, 7:30 a.m. PDT

If you were standing on Mars this morning you would have seen the Earth rise at 8:15 pm PDT and the Sun rise at 11:05 pm PDT. You also have been fairly cold when you woke up as was the lander when it woke up around sunrise with the temperature of the main computer being -25 Celsius.

All data after wake up indicated the rover and lander are in good health and today was a very successful day of moving the rover and taking science data on the lander. Sojourner did send down data today related to the composition of the rock Shark which we placed the APXS on yesterday. Analysis of this data will help determine the composition of Shark. In its move today to the nearby rock Half Dome the rover backed up turned and moved forward to deploy the APXS onto Half Dome. In navigating to Half Dome Sojourner climbed up Half Dome and was subsequently too high for the APXS to be touching the rock. The rover team is currently planning a strategy for tomorrow which may include continuing to try get the APXS down on to Half Dome and moving on to nearby rocks for APXS measurements.

The lander is also in great shape today as the high gain pointing continues to be good and the camera and ASI/MET science instruments are working as expected. Additional weather and imaging data is being collected.

As the day ends on Mars today the Earth will set at 9:35 am PDT and the Sun will set at 11:35 am PDT. For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.