Oxia - 12 Years Later |LINK|

Both missions seek to understand the environmental conditions that prevailed when Mars was young, only about half a billion years after planetary formation. At the time, the atmospheres of both planets were dominated by carbon dioxide, and both enjoyed fluvial activity. On Earth, microbial life arose under those conditions. Did the same happen on Mars? [More at link]

Oxia - 12 Years later

Launched on a Delta II rocket on December 4, 1996. The Mars Pathfinder mission was used to demonstrate that NASA could send an exploratory mission to Mars for 1/15th of the cost of the Viking budget in the 1970's. The mission was developed at a cost of under $150 million in 3 years. One of the major mission objectives was to deliver a microrover safely to the surface in order to study the surface composition. The microrover onboard was known as Sojourner. Rocks and soil were probed with an Alpha Proton X-ray Spectrometer (APXS).[6] Sojourner was powered with solar panels and a non-rechargeable battery, which greatly limited night activities. When the batteries were depleted, it could not work at night.[7] Its lithium-thionyl chloride (LiSOCl2) batteries only generated 150 watt-hours.[8] The Mars Pathfinder Mission lasted from December 1996 to March 1998. Pathfinder carried out more than 15 chemical analyses of rocks and soil, besides collecting data on the weather. Information learned through the mission suggest that, in its past, Mars was warm and wet, with liquid water on its surface and a thicker atmosphere. Depletion of the spacecraft's battery along with a drop in the spacecraft's operating temperature was believed to be why we lost communications with Pathfinder in October 1997. The mission far surpassed its expected 30-day lifetime.[9]

The crater Mojave, in the Xanthe Terra region, has alluvial fans that look remarkably similar to landforms in the Mojave Desert in the American southwest. As on Earth, the largest rocks are near the mouths of the fans. As the mixture of debris and water move downslope, the largest rocks are dropped first. Because channels start at the tops of ridges, it is believed they were formed by heavy downpours. Researchers have suggested that the rain may have been initiated by impacts.[45]Mojave is approximately 1.618 miles (2,604 meters) deep. Its depth relative to its diameter and its ray system indicate it is very young. Crater counts of its ejecta blanket give an age of about 3 million years. It is considered the most recent crater of its size on Mars, and has been identified as the probable source of the shergottite meteorites collected on Earth.[46] Shergottite is the name of one of serveal classes of meteorites that we now know came from Mars. They were blasted off the surface by large impacts at low angles.

'Vallis (plural valles) is the Latin word for valley. It is used in planetary geology for the naming of river-like features on other planets.Vallis was used for old river valleys that were discovered on Mars, when probes were first sent to Mars. In the 1970's, the Viking Orbiters caused a revolution in our conception of water on Mars; huge river valleys were found in many areas. As the years of study of Mars have gone on spacecraft cameras showed that floods of water broke through dams, carved deep valleys, eroded grooves into bedrock, and traveled thousands of kilometers.[47] [48] [49].[50] [51] [52] [53] [54] [55]

Linear ridge networks are found in various places on Mars in and around craters.[58] Ridges often appear as mostly straight segments that intersect in a lattice-like manner. They are hundreds of meters long, tens of meters high, and several meters wide. One popular idea for the origin of linear ridges is that impacts created fractures in the surface, these fractures later acted as channels for fluids. Fluids cemented the structures. With the passage of time, surrounding material was eroded away, thereby leaving hard ridges behind. However, researches are still debating the exact nature of this networks. Since the ridges occur in locations with clay, these formations could serve as a marker for clay which requires water for its formation.[59] [60]Water here could have supported past life in these locations. Clay may also preserve fossils or other traces of past life.

Chaotic terrain occurs in numerous locations on Mars, and always gives the strong impression that something abruptly disturbed the ground. Chaos regions formed long ago. By counting craters (more craters in any given area means an older surface) and by studying the valleys' relations with other geological features, scientists have concluded the channels in Oxia Palus formed 2.0 to 3.8 billion years ago.[63]

FE-5 Williams undertook the periodic US PHS (Periodic Health Status)/Without Blood Labs exam, his first, assisted by FE-4 Thirsk as CMO (Crew Medical Officer). Jeff later logged the data and stowed the equipment. A subjective evaluation was part of the test. [The assessment used the AMP (Ambulatory Medical Pack), stethoscope, oral disposable thermometer and ABPC (Automatic Blood Pressure Cuff) from the ALSP (Advanced Life Support Pack). All data were then logged on the MEC (Medical Equipment Computer) and the hardware stowed. The PHS exam is guided by special IFEP (In-Flight Examination Program) software on the MEC laptop.] 041b061a72