mercury has no known satellites .
Mercury, Venus, Earth, Mars, Neptune and Pluto.
I don't know of any planet with exactly 21 known moons. The best answer is probably "Uranus" with 27 moons (natural satellites).
Betelgeuse is a star, not a planet, so it does not have any satellites. Satellites, also known as moons, typically orbit planets, not stars.
Uranus has 27 known artificial satellites as of now. These satellites are typically referred to by numbers rather than names.
Uranus has 27 known satellites and it has a dim set of rings. The 5 major satellites of Uranus are Miranda, Ariel, Umbriel, Titania and Oberon.
Mercury has no satellites.
No satellites have been discovered yet in orbit around Mercury. As of now, the answer to the question is zero.
Neptune has 13 known satellites to this date.They are:NaiadThalassaDespinaGalateaLarissaProteusTritonNereidHalimedeSaoLaomedeiaPsamatheNeso
There are no known satellites of Mercury.
Venus has no known natural satellites or moons.
Toledo Mercurys was created in 1947.
Toledo Mercurys ended in 1962.
mercurys period number is 80
Venus has no known natural satellites (moons).
Venus has no known natural satellites or moons.
Mercury, Venus, Earth, Mars, Neptune and Pluto.
Mercury and Venus have no known natural satellites (moons).