The Inner Solar System consists of the four closest planets to the Sun: Mercury, Venus, Earth, and Mars. These planets are primarily rocky and have solid surfaces, distinguishing them from the gas giants found in the outer solar system. The inner solar system also includes the Asteroid Belt, which lies between Mars and Jupiter. In addition to the planets, the inner solar system features various smaller bodies, such as asteroids and comets. The proximity to the Sun means that these planets experience higher temperatures and have shorter orbital periods compared to those in the outer solar system.