Astronomy Practice Exam 2025 - Free Astronomy Practice Questions and Study Guide.

Most asteroids in our solar system primarily reside in the region between Mars and Jupiter, known as the asteroid belt. This area contains a vast number of rocky bodies that vary in size, with some being quite large, like Ceres, which is classified as a dwarf planet. The gravitational influence of Jupiter plays a crucial role in shaping the structure and population of the asteroid belt. It prevents these rocky bodies from coalescing into a larger planet due to its strong gravitational pull, leading to a wide distribution of asteroids instead.

Asteroids that are found closer to the inner solar system, such as those between Venus and Earth, are much less numerous. Similarly, the region between Neptune and Pluto is populated by a different class of objects, such as the trans-Neptunian objects and Kuiper Belt objects, rather than asteroids. The region between Mercury and Venus is also not recognized for hosting significant numbers of asteroids. Therefore, the designation of the area between Mars and Jupiter as the primary residence of asteroids is well-supported by both observational data and understanding of solar system dynamics.