This document discusses how the temperature of planets in the solar system varies based on their distance from the sun. It explains that the planet closest to the sun, Mercury, has the highest temperature, while the farthest planet, Neptune, has the lowest temperature. It also notes that Venus has the hottest temperature overall due to its dense atmosphere trapping heat. The document seeks to teach students about how the sun influences temperatures in the solar system and how planets' distances from the sun impact their surface temperatures.