A Nasa rover on Mars was struck by charged particles from a solar storm that swept the Red Planet last month.
The cameras on the Curiosity rover, which landed there 12 years ago, recorded white streaks and specks falling “like snow” on May 20, as charged particles hit the lenses.
Nasa said that if astronauts had been standing next to the rover at the time, they would have received a radiation dose of 8,100 micrograys.
“Mars scientists have been anticipating epic solar storms since the Sun entered a period of peak activity called solar maximum earlier this year,” Nasa said on Monday.
“Over the past month, Nasa’s Mars rovers and orbiters have provided researchers with front-row seats to a series of solar flares and coronal mass ejections that have reached Mars – in some cases, even causing Martian auroras.”
The camera on the agency's Odyssey orbiter, which is used for orientation, was also inundated by energy from solar particles, putting it temporarily off line.
Mars has a very thin atmosphere that leaves it vulnerable to charged particles from the Sun.
Earth has also been struck by particles in the past few months, with the most powerful solar storm in more than two decades on May 10 that resulted in spectacular auroras from the UK to Tasmania.
"Our home planet is shielded from charged particles by a robust magnetic field, which normally limits auroras to regions near the poles," the space agency said.
"Mars lost its internally generated magnetic field in the ancient past, so there’s no protection from the barrage of energetic particles.
"When charged particles hit the Martian atmosphere, it results in auroras that engulf the entire planet."
