Phobos and Deimos


Mars has two small moons. Phobos, which is about 11.5 km across, was imaged on 26 March, 2019, as in moved across the face of the Sun from Curiosity rover’s post of view. Deimos, which is only about 2.3 km across, was 17 March. Phobos doesn’t completely cover the Sun, so Curiosity saw what could be considered an annular eclipse. Deimos is so small compared to the disk of the Sun, astronomers would say it transited the Sun.

Image Credits: NASA

Bonus GIF—This series of images shows the shadow of Phobos as it sweeps over Curiosity and darkens the sunlight near sunset on 25 March.

Petrified Dunes on Mars


mcam-sol1087_with-scalebarThe crossbedding in the sandstone of this ridge on a lower slope of Mars’ Mount Sharp is typical of windblown sand dunes that have petrified. The Curiosity rover used its Mastcam to capture this panorama on 27 August, 2015. Similar sandstone is common in the American Southwest. Click the image to embiggen it.

Image Credit—NASA