Here's why:

* AU stands for Astronomical Unit. It is a unit of distance used to measure distances within our solar system. One AU is defined as the average distance between the Earth and the Sun, which is approximately 149.6 million kilometers (93 million miles).

* Planets orbit the Sun in ellipses, not perfect circles. This means their distance from the Sun varies throughout their orbit.

* 100 AU is a very large distance. It's far beyond the orbit of Pluto and even extends beyond the Kuiper belt, a region of icy objects beyond Neptune.

Therefore, the distance from the Sun varies depending on the celestial object in question and its position in its orbit.