small irregular body shaped body formed by colliding matter
ASTEROIDS
Planets, exoplanets, asteroids. They're all sattelites of the sun.
I don't think so because we are discovering more Pluto like bodies in the solar system and we either have to make these planets or put Pluto into a new category (of Dwarf Planets) along with these.
Condensations of Ices meant that there was more solid material. · Planetesimals that accreted in the outer solar system contained large amounts of ice in addition to metal and rock. The solid objects that reside in the outer solar system today, such as comets and the moons of the Jovian planets, still show this ice-rich composition. · With the large masses of icy planetesimals, their gravity became strong enough to capture and hold some of the hydrogen and helium gas that made up the vast majority of the surrounding solar nebula. As the growing planets accumulated gas, their gravity grew stronger still, allowing them to capture even more gas. Ultimately, the Jovian planets grew so much that they bore little resemblance to the icy seeds from which they started, instead ending up with large abundances of hydrogen and helium gas. Astronomers believe that Jupiter is so large because its position in the solar system was perfect for capturing the most dust and gas. Reasons that other planets aren't so large are planets that formed close to the sun couldn't capture as much gas and dust because it was moving too swiftly, and planets furthest form the sun couldn't capture as much gas and dust because there simply wasn't that much. Saturn also formed in a place in the solar system where it could capture a lot of dust and gas. However, its diameter is 22,448 kilometers smaller than Jupiter's.