Curiosity: Tracking Sunspot Activity With Mars Rover

NASA’s Curiosity Mars rover is currently busy checking out bedrock types on Mars’ Mount Sharp as well as getting ready for a drill test. But Curiosity stall has time to looking up regularly to monitor sunspots on the side of the sun facing away from Earth.

Scientists temporarily have no other system for observing the sun from the opposite side of the solar system from Earth. About once a month the sun completes a rotation, faster near its equator than near its poles.

Data about sunspots that develop before they rotate into view of Earth and Earth-orbiting spacecraft is beneficial in predicting space-weather effects of solar emissions related to sunspots. Large sunspots can be seen in images from Curiosity’s Mast Camera (Mastcam).

In the image above, an eruption from the surface of the sun can be seen in the lower left portion of the July 6, 2015, image from NASA’s Earth-orbiting Solar Dynamics Observatory (SDO). The eruption originated from a location on the surface where NASA’s Curiosity Mars rover had been tracking a sunspot in late June and early July. The image was taken by the Atmosphere Imaging Assembly on SDO using the instrument’s 131-Angstrom wavelength channel, which is sensitive to hot solar flares.

Why the temporary lack of far side of the sun sunspot monitory? NASA’s STEREO-A spacecraft, which monitors the sun, is now almost exactly behind the sun from Earth’s perspective, but for just that reason it is temporarily out of communication.

Radio transmissions that pass too close sun get disrupted by it. Similarly, communication with Curiosity also dropped out last month when Mars passed nearly behind the sun. The rover resumed full communication and operations in late June, while information from STEREO-A is expected to begin again this month.

“Tracking the sunspot activity on the far side of the sun is useful for space-weather forecasting,” said Yihua Zheng, project leader for NASA Space Weather Services at NASA Goddard Space Flight Center, Greenbelt, Maryland. “It helps us monitor how the sunspots evolve and grow before they become visible from this side.”


This image shows sunspots as viewed by NASA’s Curiosity Mars rover from June 27 to July 8, 2015. Credit: NASA/JPL-Caltech/MSSS/Texas A&M University

Other than its sunspot monitoring, Curiosity is looking at rocks near “Marias Pass.” Later this month, a test is planned for the percussion mechanism on the rover’s sample-collecting drill, which had a brief short circuit during transfer of sample material collected four months ago.