Curiosity captures a martian day, from dawn to dusk

When NASA’s Curiosity Mars rover is not on the transfer, it really works fairly properly as a sundial, as seen in two black-and-white movies recorded on Nov. 8, the 4,002nd Martian day, or sol, of the mission. The rover captured its personal shadow shifting throughout the floor of Mars utilizing its black-and-white Hazard-Avoidance Cameras, or Hazcams.

Directions to document the movies have been a part of the final set of instructions beamed as much as Curiosity simply earlier than the beginning of Mars’ solar conjunction, a interval when the sun is between Earth and Mars. As a result of plasma from the sun can intervene with radio communications, missions maintain off on sending instructions to Mars spacecraft for a number of weeks throughout this time. (The missions weren’t completely out of contact: They nonetheless radioed again common well being check-ins all through conjunction.)

Rover drivers usually depend on Curiosity’s Hazcams to identify rocks, slopes, and different hazards that could be dangerous to traverse. However as a result of the rover’s different actions have been deliberately scaled again simply previous to conjunction, the staff determined to make use of the Hazcams to document 12 hours of snapshots for the primary time, hoping to seize clouds or dust devils that would reveal extra concerning the Pink Planet’s climate.

When the pictures got here all the way down to Earth after conjunction, scientists did not see any climate of observe, however the pair of 25-frame movies they put collectively do seize the passage of time. Extending from 5:30 a.m. to five:30 p.m. native time, the movies present Curiosity’s silhouette shifting because the day strikes from morning to afternoon to night.

The primary video, that includes pictures from the entrance Hazcam, seems to be southeast alongside Gediz Vallis, a valley discovered on Mount Sharp. Curiosity has been ascending the bottom of the 3-mile-tall (5-kilometer-tall) mountain, which sits in Gale Crater, since 2014.

Because the sky brightens throughout dawn, the shadow of the rover’s 7-foot (2-meter) robotic arm strikes to the left, and Curiosity’s entrance wheels emerge from the darkness on both aspect of the body. Additionally turning into seen on the left is a round calibration goal mounted on the shoulder of the robotic arm. Engineers use the goal to check the accuracy of the Alpha Particle X-ray Spectrometer, an instrument that detects chemical parts on the Martian floor.

In the course of the day, the entrance Hazcam’s autoexposure algorithm settles on publicity occasions of round one-third of a second. By dusk, that publicity time grows to greater than a minute, inflicting the everyday sensor noise often called “sizzling pixels” that seems as white snow throughout the final image.

The second video exhibits the view of the rear Hazcam because it seems to be northwest down the slopes of Mount Sharp to the ground of Gale Crater. The rover’s proper rear wheel is seen, together with the shadow of Curiosity’s energy system. A small black artifact that seems on the left halfway by means of the video, in the course of the seventeenth body, resulted from a cosmic ray hitting the digital camera sensor.

Likewise, the brilliant flashing and different noise on the finish of the video are the results of warmth from the spacecraft’s energy system affecting the Hazcam’s picture sensor.

These pictures have been re-projected to appropriate the wide-angle lenses of the Hazcams. The speckled look of the pictures, particularly outstanding within the rear-camera video, is because of 11 years of Martian dust selecting the lenses.