yes 15
As of 2011, the planet Uranus has 27 known moons. (list at the related question)
No. He discovered great moons, which, had they not been orbiting planets might have been considered planets themselves, but the first new planet since antiquity was Uranus, discovered by Sir William Herschel.
Chiron, the moon of Pluto is not know to have any moons
Galileo Galilei did not discover any moons orbiting Saturn; his observations were primarily focused on Jupiter. He is credited with discovering four large moons of Jupiter, known as the Galilean moons, in 1610. Saturn's moons were discovered later, with the first being Titan, which was observed by Christiaan Huygens in 1655.
Yes. Jupiter has 67 moons.
Maybe
no it doesn't
mercury has no moons or rings therefore it has nothing orbiting it although it orbits the sun.
No
Venus does not have any moons. Despite being similar in size and composition to Earth, it lacks natural satellites, a fact that has intrigued scientists for centuries. Various missions and observations have confirmed this absence, with no moons discovered since the dawn of space exploration.
Mercury does not have any moons. It is the only planet in our solar system that does not have any natural satellites orbiting around it.
Venus does not have any moons, so they couldn't be discovered.