In a first, ESA's Mars Express orbiter imaged the Martian moons Phobos and Deimos together on 5 November 2009.
Pioneering images of both Martian moons
The images were acquired with the Super Resolution Channel (SRC) of the High Resolution Stereo Camera (HRSC). The camera took 130 images of the moons on 5 November at 9:14 CET in a span of 1.5 minutes at intervals of 1s, speeding up to 0.5-s intervals toward the end. The image resolution is 110 m/pixel for Phobos and 240 m/pixel for Deimos - Deimos was more than twice as far from the camera.
The Super Resolution Channel of the HRSC uses an additional lens, which has a very narrow field of view of just 0.5°, providing four times the magnification than otherwise providing four times the resolution of the HRSC colour stereo channel. Phobos, the larger of the two moons, orbits closer to the Red Planet, circling it every 7 hours and 39 minutes. It travels faster relative to Mars than the Moon relative to Earth. It was