Where is Deimos?

Mars Express image of the moons Phobos (foreground) and Deimos (background). Credit: ESA/DLR/FU Berlin (G. Neukum)

Despite more than a century of observations, the orbit of the Martian moon Deimos is still not known to a high degree of accuracy, but a new study using images taken by ESA’s Mars Express orbiter has provided the best orbital model to date.

135 years have passed since Asaph Hall discovered Phobos and Deimos, two small companions of the planet Mars. Since that time, the satellites have been imaged innumerable times from the Earth and from spacecraft, including recent measurements by the panoramic cameras on the Mars Exploration Rovers and instruments on the Mars Reconnaissance Orbiter.

Full Story: http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=50842