zero.
There is no "Murcury" bu there is a planet Mercury, it has no satellites natural or artificial that remain in orbit around the planet.In 1973 Mariner 10 flew relatively close to Mercury and photographed some of the surface.
murcury
Approx 253360 minutes
Well, Uranus doesn't "surround" Neptune - they are many, many millions of miles apart. The only things that surround Neptune are it's satellites. In the area beyond the planet Neptune are many "trans-Neptunian objects", ice planetoids, mostly. Among these is Pluto, considered a planet for so many years, but now classed as a "dwarf planet" or "trans-Neptunian object".
Looks like we've got a jokester... Uranus has 27 known satellites.
no
rocks
It is murcury
It has 3 satellites!
venus
Murcury
it does not have an atmosphere