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Videos from the rover show its shadow moving across the Martian surface during a 12-hour sequence while Curiosity remained parked.<\/em><\/p>\n When NASA\u2019s Curiosity Mars rover isn\u2019t on the move, it works pretty well as a sundial, as seen in two black-and-white videos recorded on Nov. 8, the 4,002nd Martian day, or sol, of the mission. The rover captured its own shadow shifting across the surface of Mars using its black-and-white Hazard-Avoidance Cameras, or Hazcams.<\/p>\n Instructions to record the videos were part of the last set of commands beamed up to Curiosity just before the start of Mars solar conjunction, a period when the Sun is between Earth and Mars. Because plasma from the Sun can interfere with radio communications, missions hold off on sending commands to Mars spacecraft for several weeks during this time. (The missions weren\u2019t totally out of contact: They still radioed back regular health check-ins throughout conjunction.)<\/p>\n Rover drivers normally rely on Curiosity\u2019s Hazcams to spot rocks, slopes, and other hazards that may be risky to traverse. But because the rover\u2019s other activities were intentionally scaled back just prior to conjunction, the team decided to use the Hazcams to record 12 hours of snapshots for the first time, hoping to capture clouds or dust devils that could reveal more about the Red Planet\u2019s weather.<\/p>\n When the images came down to Earth after conjunction, scientists didn\u2019t see any weather of note, but the pair of 25-frame videos they put together do capture the passage of time. Extending from 5:30 a.m. to 5:30 p.m. local time, the videos show Curiosity\u2019s silhouette shifting as the day moves from morning to afternoon to evening.<\/p>\n The first video, featuring images from the front Hazcam, looks southeast along Gediz Vallis, a valley found on Mount Sharp. Curiosity has been ascending the base of the 3-mile-tall (5-kilometer-tall) mountain, which sits in Gale Crater, since 2014.<\/p>\n As the sky brightens during sunrise, the shadow of the rover\u2019s 7-foot (2-meter) robotic arm moves to the left, and Curiosity\u2019s front wheels emerge from the darkness on either side of the frame. Also becoming visible at left is a circular calibration target mounted on the shoulder of the robotic arm. Engineers use the target to test the accuracy of the Alpha Particle X-ray Spectrometer, an instrument that detects chemical elements on the Martian surface.<\/p>\n In the middle of the day, the front Hazcam\u2019s autoexposure algorithm settles on exposure times of around one-third of a second. By nightfall, that exposure time grows to more than a minute, causing the typical sensor noise known as \u201chot pixels\u201d that appears as white snow across the final image.<\/p>\n The second video shows the view of the rear Hazcam as it looks northwest down the slopes of Mount Sharp to the floor of Gale Crater. The rover\u2019s right rear wheel is visible, along with the shadow of Curiosity\u2019s power system. A small black artifact that appears at the left midway through the video, during the 17th frame, resulted from a cosmic ray hitting the camera sensor. Likewise, the bright flashing and other noise at the end of the video are the result of heat from the spacecraft\u2019s power system affecting the Hazcam\u2019s image sensor.<\/p>\n These images have been re-projected to correct the wide-angle lenses of the Hazcams. The speckled appearance of the images, especially prominent in the rear-camera video, is due to 11 years of Martian dust settling on the lenses.<\/p>\n Curiosity was built by NASA\u2019s Jet Propulsion Laboratory, which is managed by Caltech in Pasadena, California. JPL leads the mission on behalf of NASA\u2019s Science Mission Directorate in Washington.<\/p>\n For more about Curiosity, visit:<\/p>\n <\/strong><\/p>\n Andrew Good Karen Fox \/ Alana Johnson 2023-189<\/p>\n<\/div>\nMore About the Mission<\/strong><\/h3>\n
News Media Contacts<\/strong><\/h3>\n
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433
andrew.c.good@jpl.nasa.gov<\/p>\n
NASA Headquarters, Washington
301-286-6284 \/ 202-358-1501
karen.c.fox@nasa.gov \/ alana.r.johnson@nasa.gov<\/p>\n