The local Solar System consists of the following objects:
- One star, the Sun
- Eight major planets
- Several minor planets, including dwarf planets like Pluto and asteroids in the asteroid belt
- Natural satellites that orbit the planets
- Smaller bodies, such as comets, Kuiper belt objects and Oort cloud objects
The Sun is the only star in the solar system that generates almost all the energy for the rest of the solar system.
- Note: Do NOT attempt to look at the Sun using a telescope or binoculars or with the naked eye. Doing so can cause permanent damage to the eye.
There are 8 major planets orbiting the Sun, and they are arranged in this order: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
- A major planet must fulfil 3 criteria:
  - It must orbit the Sun.
  - It must be big enough for gravity to force it into a spherical shape.
  - It must clear the neighbourhood objects round its orbit.
- Pluto is no longer a major planet and is now classified as a dwarf planet since 2006, as it did not fulfil the last criterion as mentioned above.

There are several minor planets orbiting the Sun. These include:
- Dwarf planets: Ceres, Pluto, Haumea, Makemake and Eris.
- Asteroids that orbit the Sun in the asteroid belt between Jupiter and Mars.

Some planets and minor planets have natural satellites that orbit them.
- The Earth has a Moon, which is our own natural satellite.
- All other planets except Mercury and Venus have natural satellites. Jupiter, for instance, currently has 78 satellites.
- Some of the dwarf planets and asteroids have natural satellites as well.

Comets have highly elongated orbits that take them very close to the Sun and out of the solar system. They are made of ice and dust that sublimate into a very long tail when close to the Sun.

Beyond the Solar System lies the Kuiper belt, where small icy objects orbit the Sun over a long period of time. This is the area where the dwarf planets, viz., Pluto, Eris, Makemake and Haumea are found.
Beyond the Kuiper belt is the Oort Cloud, which astronomers theorised as the origin of comets. These are objects that are small and icy, and this area is usually considered the edge of the solar system.

6.02 - Solar System (I)

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