Only a handful of days after NASA gave up on the Mars rover Opportunity, sister rover Curiosity did something strange by suddenly placing herself into standby mode, alarming technicians on Earth.

After encountering an error during bootup and subsequently dropping itself into safe mode on February 15, NASA Mars rover Curiosity aroused alarm Earthside that it was possibly following in the footsteps of its now permanently-shuttered sister rover Opportunity.

"We're still not sure of its exact cause and are gathering the relevant data for analysis," observed Curiosity deputy project manager Steven Lee with NASA's Jet Propulsion Laboratory in California, cited by Space.com.

"The rover experienced a one-time computer reset but has operated normally ever since," Lee elaborated, adding that subsequent reboots of the Curiosity rover have gone without a hitch, "which is a good sign."

Mars rover Opportunity, which had been radio silent since June 10, 2018, was formally declared defunct by NASA on February 13.

Opportunity arrived on the Martian surface on January 25, 2004, where it was only expected to function for an estimated 90 days. The rover continued to travel over the landscape of the fourth planet, collecting and transmitting data back to Earth for over 14 years.

NASA technicians report that following the initial boot error and standby move, Curiosity has followed instructions to the letter, and has shown no additional software anomalies. Ground-based crews are, however, working to identify what caused the glitch in the first place while confirming that key data is not lost.

"We are limiting commands to the vehicle to minimize changes to its memory," Lee noted, adding that technicians "don't want to destroy any evidence of what might have caused the computer reset."