Phobos (moon) energy due to wind blowing dust off of its solar panels, took several short-exposure photographs of the night sky from the surface of Mars. Phobos and Deimos are both clearly visible in the photograph. The Soviet Union undertook the Phobos program with two probes, both launched successfully in July 1988. "Phobos 1" was accidentally shut down by an erroneous command from ground control issued in September 1988 and lost while the craft was still en route. "Phobos 2" arrived at the Mars system in January 1989 and, after transmitting a small amount of data and imagery but shortly before beginning
Solar System model Solar System model Solar System models, especially mechanical models, called "orreries", that illustrate the relative positions and motions of the planets and moons in the Solar System have been built for centuries. While they often showed relative sizes, these models were usually not built to scale. The enormous ratio of interplanetary distances to planetary diameters makes constructing a scale model of the Solar System a challenging task. As one example of the difficulty, the distance between the Earth and the Sun is almost 12,000 times the diameter of the Earth. If the smaller planets are to be easily visible to