The Phoenix Mars Lander used its Robotic Arm during the mission’s 15th Martian sol to test the “sprinkling” method for delivering small samples of soil to instruments on the lander deck. The “movie” shown here is a sequence of four images from the spacecraft’s Surface Stereo Imager, and demonstrates the actions of Phoenix for a 20 minute period. The sprinkling was tested because a couple of days ago, the first attempt at bringing soil samples to the scientific instruments was unsuccessful. The soil, when just dumped as a whole onto Phoenix’s deck, clumped together and wouldn’t go through a screen that brings the materials to the TEGA instrument to analyze the soil. The sprinkling technique, by contrast, holds the scoop at a steady angle and vibrates the scoop by running the motorized rasp located beneath the scoop. This gently jostles some material out of the scoop to the target below.
This method seems to distribute the material better, and “unclumps” the frozen clods of soil. For this test, the target was near the upper end the cover of the Microscopy, Electrochemistry and Conductivity Analyzer instrument suite, or MECA. The cover is 20 centimeters (7.9 inches) across. The scoop is about 8.5 centimeters (3.3 inches) across.
Based on the test’s success in delivering a small quantity and fine-size particles, the Phoenix team plans to use the sprinkle method for delivering more samples to MECA and then to the Thermal and Evolved-Gas Analyzer, or TEGA. The delivery to MECA’s Optical Microscope, will be via the port in the MECA cover, visible at the bottom of the image.
Meanwhile, Phoenix will continue a set of atmospheric observation begun during the Martian evening on Tuesday in coordination with overhead passes of NASA’s Mars Reconnaissance Orbiter. These take advantage of opportunities for instruments on Phoenix and on the orbiter to examine the same column of atmosphere simultaneously from above and below.
“It allows us to put the Phoenix measurements into global perspective and gives a ground level calibration for the orbiter’s measurements,” said Phoenix Project Scientist Leslie Tamppari of the Jet Propulsion Laboratory.
Source: Phoenix News