Phobos (moon) was proposed to place an orbiter in Mars orbit by 2021 to study Phobos and Deimos through a series of close flybys. The mission is called Phobos And Deimos & Mars Environment (PADME). Two other Phobos missions that were proposed for the Discovery 13 selection included a mission called "Merlin", which would flyby Deimos but actually orbit and land on Phobos, and another one is "Pandora" which would orbit both Deimos and Phobos. The Japanese Aerospace Exploration Agency (JAXA) unveiled in 9 June 2015 the Martian Moons Exploration (MMX), a sample return mission targeting Phobos. MMX will land and collect
Discovery and exploration of the Solar System Domenico Cassini later discovered four more moons of Saturn and the Cassini division in Saturn's rings. Edmond Halley realised in 1705 that repeated sightings of a comet were recording the same object, returning regularly once every 75–76 years. This was the first evidence that anything other than the planets orbited the Sun. Around this time (1704), the term "Solar System" first appeared in English. In 1781, William Herschel was looking for binary stars in the constellation of Taurus when he observed what he thought was a new comet. Its orbit revealed that it was a new planet, Uranus, the first