digging in a different trench phoenix ' s human arm connected with a harsh surface that has scientists excited about the concept of then uncovering an icy layers . " we have carved a trench and exposed a hard texture at the same location as the melt layer in our other trench , " said washington university robotic arm investigator for phoenix , john arvidson . the program tried at least eight once to enter the boundary , but was unsuccessfully . as a resulted the elbow went into a holding phase , await its next commands .
A robotic arm has been used for scientific discoveries.