generally the men who discover them.
To refer which of the planets is which its like why do you have a name
Yes - all planets names begin with a capital letter.
Grind Planets was created in 2005.
VGA Planets was created in 1992.
Two Planets was created in 1897.
Journey to the Planets was created in 1982.
Planets of the Universe was created in 2001.
Toronto Planets was created in 1993.
The Planets are Blasted was created in 2009.
Planets of Adventure was created in 1949.
Between Planets was created in 1951.
The Outer planets are often referred to as Gaseous planets. The others are the "inner planets" or rocky planets.