Source: Curiosity Rover Spots Weird Tube-Like Structures on Mars Vasavada reported that the eye-catching features are very small, probably on the order of a millimeter or two (0.04 to 0.08 inches) in width, with the longest of the features stretching to roughly 5 millimeters (0.2 inches). "So, they are tiny," he told Inside Outer Space. Serendipitously, they were first spotted in black and white imagery. The features were compelling enough for the science team to roll Curiosityback to examine them further, making use of MAHLI — a focusable color camera mounted on the rover's arm, Vasavada said. "These were unique enough, given the fact that we didn't know they were there … [that] we thought we should go back," Vasavada explained. Curiosity team member Christopher Edwards, a planetary geologist at Northern Arizona University in Flagstaff, also made note of the plan to wheel Curiosity back to study the dark-toned "stick-like" features. "This site was so interesting that we backtracked to get to where the rover was parked for this plan," Edwards wrote in a Jan. 3 mission update. "In the work space in front of the rover, we have some very peculiar targets that warranted some additional interrogation." Source: Curiosity (rover) - Wikipedia Curiosity is a car-sized rover designed to explore Gale Crater on Mars as part of NASA's Mars Science Laboratory mission (MSL).[3] Curiosity was launched from Cape Canaveral on November 26, 2011, at 15:02 UTC aboard the MSL spacecraft and landed on Aeolis Palus in Gale Crater on Mars on August 6, 2012, 05:17 UTC.[7][8][13] The Bradbury Landing site was less than 2.4 km (1.5 mi) from the center of the rover's touchdown target after a 560 million km (350 million mi) journey.[9][14] The rover's goals include an investigation of the Martian climate and geology; assessment of whether the selected field site inside Gale Crater has ever offered environmental conditions favorable for microbial life, including investigation of the role of water; and planetary habitability studies in preparation for human exploration.[15][16] In December 2012, Curiosity's two-year mission was extended indefinitely.[17]On August 5, 2017, NASA celebrated the fifth anniversary of the Curiosityrover landing and related exploratory accomplishments on the planet Mars.[18][19] I think we've found a target for a sample and return mission. Bob Wilson
