The Member of Solar System, Part.2

The Member of Solar System, Part.2

The member of solar system consists of: Sun, planet, asteroid, comet, meteor and satellite.

1. Sun => click here

2. Planet


Planet comes from the world planetair (Greek Language), that means adventurer. The general conference of International Astronomical Union that is carried out in Praha city, Ceko, on date august 24th, 2006 to produces a new definition about planet.

Planet is celestial bodies that orbits the sun, that has round shape and the only dominant object in its orbit.

From the result of the general conference of IAU in praha, a number of planet in our solar system becomes eight. Pluto that formerly is included planet found in our solar system, now it is not included anymore. That thing because Pluto is assumed not big planet, but dwarf planet. The reason that Pluto is not assumed as planet in our solar system is because around orbit of Pluto is many found objects of the same kind in the form of TNO (Trans Neptunion Objects).

TNO is an object of solar system that orbits or passes beyond orbit of planet Neptune.

Meanwhile the characteristics of planet according to International Astronomical Union are as follows
a. It orbits the sun.
b. It has enough mass for its gravitational force.
c. It has eliminated another objects around its orbit.
d. It has no light source.
e. It has satellite.

If we consider the characteristics of the planet, the Pluto is not included planet, but it is a dwarf planet.

Meanwhile the characteristics of dwarf planet are:
a. It orbits the sun.
b. It has the shape of almost round.
c. It has enough mass for its gravitational force.
d. It has not eliminated yet another objects around its orbit.
e. It is not satellite.

From the characteristics, celestial body in our solar system that included dwarf planet involves Pluto, cares and xena. Meanwhile charon is not included into the group of dwarf planet, because it is satellite of Pluto.