A new picture taken from the surface of Mars by NASA’s rover Curiosity shows the moon Phobos, one of the two moons orbiting the red planet, moving across the face of the sun.
The image captured a moment during a partial eclipse, with Phobos just jutting into Mars’s view of the sun, the Daily Mail reported. Though Mars may be a little further away from the sun than Earth, it would still be damaging to look directly into its light. If Curiosity pointed its regular lens straight at the sun, it could have been destroyed. So instead the rover used a neutral density filter, cutting down the sun’s intensity by a factor of 1,000, according to NBC News.
Curiosity has taken hundreds of images during the partial eclipse, and is set to take more during another eclipse involving Deimos, Mars’s other moon. But most have not yet been send to Earth because of the limitations on the rover’s ability to transmit data.