1. Astronomical Unit (AU)
* Definition: The average distance between the Earth and the Sun.
* Value: 149.6 million kilometers (93 million miles)
* Use: Most common unit for measuring distances within the solar system. It's convenient because it avoids using extremely large numbers.
2. Kilometers (km) and Miles (mi)
* Definition: Standard units of distance used on Earth.
* Use: While less common than AU, they are sometimes used for distances within the solar system, especially when comparing to familiar earthly distances.
3. Light-years (ly)
* Definition: The distance light travels in one year.
* Value: 9.461 trillion kilometers (5.879 trillion miles)
* Use: While light-years are most commonly used for interstellar distances, they can be used for some distances within the solar system (for example, the distance to the outer edges of the Kuiper Belt).
Example:
* The distance from the Sun to Jupiter is approximately 5.2 AU.
* The distance from the Sun to Pluto is about 39.5 AU.
Which Unit to Use:
* AU: Ideal for most distances within the solar system.
* Kilometers or Miles: Useful for comparing to familiar earthly distances.
* Light-years: Rarely used for distances within the solar system, but can be used for very large distances, like the outer edges of the Kuiper Belt.
