The Nebular Hypothesis is the prevailing theory that explains the formation of the solar system from a giant cloud of gas and dust called the solar nebula.

The solar nebula was composed of hydrogen, helium, dust, and ice, with trace amounts of other elements.

The planets formed through a combination of the collapse of the solar nebula, the collision of planetesimals, and the accretion of gas and dust.

Accretion is the process by which the planets grew in size by accumulating mass from the surrounding solar nebula.

The four inner planets are Mercury, Venus, Earth, and Mars.

The four outer planets are Jupiter, Saturn, Uranus, and Neptune.

Pluto was once considered the ninth planet, but was reclassified as a dwarf planet in 2006.

Ganymede is the largest moon in the solar system, and is larger than the planet Mercury.

Titan is the only moon in the solar system known to have an atmosphere.

Halley's Comet is known for its long, flowing tail and is visible from Earth every 76 years.

The Main Asteroid Belt is located between Mars and Jupiter and contains millions of asteroids.

The Kuiper Belt is a region beyond the orbit of Neptune and contains millions of icy bodies.

The Oort Cloud is a cloud of comets located at the edge of the solar system.

The Oort Cloud is the region of the solar system where comets originate.

Gravity is the force that holds the solar system together.