NASA's Curiosity Mars Rover captures a Martian day, from dawn to dusk

Videos from the rover show its shadow moving across the surface of Mars during a 12-hour sequence while Curiosity remains stationary.

when NASAcuriousity Mars The rover is not in motion, it works well like a sundial, as shown in two black-and-white videos recorded on November 8, the 4002nd Martian day, or sol, of the mission. The rover captured its shadow moving across the surface of Mars using black-and-white hazard-avoidance cameras, or Hazcams.

The instructions to record the videos were part of the last set of commands sent to Curiosity before the beginning of Mars' solar conjunction, the period when the Sun is between Earth and Mars. because plasma From the Sun can interfere with radio communications, and missions stop sending commands to the Mars spacecraft for several weeks during this time. (The missions were not completely out of contact: they still radioed regular medical checks throughout the synchronization period.)

While stationary for two weeks during Mars' solar conjunction in November 2023, NASA's Curiosity rover used Hazcam's front and rear black-and-white cameras to capture 12 hours of a Martian day. The rover's shadow appears on the surface in these images taken by the Hazcam foreground rover. Credit: NASA/Jet Propulsion Laboratory-California Institute of Technology

Rover drivers typically rely on Curiosity's Hazcams to spot rocks, cliffs and other hazards that would be risky to traverse. But because the rover's other activities were deliberately curtailed just before the conjunction, the team decided to use Hazcams to record 12 hours of footage for the first time, in hopes of capturing clouds or dust devils that could reveal more about the Red Planet's weather.

When the images arrived at Earth after the conjunction, the scientists didn't see any noticeable weather, but the two 25-frame videos they stitched together capture the passage of time. The videos span from 5:30 a.m. to 5:30 p.m. local time, and show Curiosity's silhouette changing as the day transitions from morning to afternoon to evening.

The first video, showing images from the Hazcam front, looks southeast along Gediz Vallis, the valley on Mount Sharp. Curiosity has been climbing to the base of the 3-mile (5-kilometer) mountain, located in Gale Crater, since 2014.

As the sky brightens during sunrise, the shadow of the rover's 7-foot (2 meter) robotic arm moves to the left, and Curiosity's front wheels emerge from the darkness on either side of the frame. Also shown on the left is a circular calibration target mounted on the shoulder of the robotic arm. Engineers use the target for testing Accuracy Subordinate Alpha particle X-ray spectroscopyAn instrument that detects chemical elements on the surface of Mars.

At midday, the Hazcam's front-facing automatic exposure algorithm settles on exposure times of about a third of a second. By nightfall, the exposure time increases to more than a minute, causing typical sensor noise known as “hot pixels” to appear as white snow across the final image.

Curiosity's Hazcam rear camera captured the shadow of the rover's rear section in this 12-hour view as it headed toward the floor of Gale Crater. A variety of factors cause various image defects, including black spots, the distorted appearance of the sun, and rows of white pixels sticking out from the sun. Image source: NASA/JPL-Caltech

The second video shows the rear view of Hazcam looking northwest down the slopes of Mount Sharp to the floor of Gale Crater. The rover's right rear wheel is visible, along with Curiosity's shadow OS. A small black artifact appears on the left in the middle of the video, during the 17th frame, caused by Cosmic rays Hit the camera sensor. Likewise, the bright flashes and other noise at the end of the video are the result of heat from the spacecraft's power system affecting the Hazcam's image sensor.

These images have been reprojected to correct for the Hazcams' wide-angle lenses. 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.

More about the mission

Curiosity was built by NASA's Jet Propulsion Laboratory, which is operated by the California Institute of Technology in Pasadena, California. JPL is leading the mission on behalf of NASA's Science Mission Directorate in Washington.