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
Goode Solar Telescope in order to reduce the solar heat load on subsequent optics. The GST is mounted on an equatorial mount made by DFM Engineering inside a ventilated dome resembling 5/8 of a sphere. The Goode Solar Telescope deploys adaptive optical systems to mitigate image blur caused by atmospheric turbulence. The system AO308 is routinely used for the vast majority of observations and serves all post-focus instruments expect of CYRA. AO308 is a "classical" adaptive optics system. It uses a Shack–Hartmann wavefront sensor that measures the average wavefront aberration over a field of view of 10 arcseconds and a single deformable mirror