The number of moons is constantly changing for some planets as they are discovered, but at the last official count there are 166 moons, with more than 20 waiting to be recognized as moons. This count is only of the moons... More » Science Astronomy Planets

The solar system includes all celestial bodies that are pulled in by the Sun's gravitational force, including the eight planets, dwarf planets, comets, asteroids, meteors, meteorites, moons, the Kuiper belt and the Oort ... More »

The exact number of solar systems is not known. According to NASA, there are more than 100 billion galaxies within the universe. One of these galaxies is the Milky Way galaxy, where our solar system is located. More »

Gravity is the force that keeps all of the planets, dwarf planets, moons, asteroids and comets orbiting the Sun. The force of gravity is inversely proportional to the distance of any two objects. This means that objects ... More »

The characteristics that the outer planets have in common include their large size and their large number of moons when compared with the inner, or terrestrial, planets. They also lack solid surfaces, and as far as astro... More »

The planetary system in which the Sun, Earth and nearby planets are located is called the Solar System, with the first letters capitalized. Other networks of planets orbiting stars are called planetary systems and are na... More »

According to NASA, astronomers have discovered at least 146 moons orbiting planets in Earth's solar system. As of 2014, 27 more moons await official confirmation of their discovery. This total does not include the six mo... More »