* Distance and Solar Radiation: The farther a planet is from the sun, the less solar radiation it receives. The intensity of sunlight decreases rapidly with distance, following an inverse square law. This means that a planet twice as far from the sun receives only one-quarter the amount of sunlight.
* Atmosphere: The presence and composition of an atmosphere can also affect a planet's temperature. Planets like Uranus and Neptune have very thin atmospheres, offering little insulation from the cold of space.
* Internal Heat: Some planets generate internal heat from radioactive decay in their cores. However, this is a relatively minor source of heat compared to solar radiation for most planets.
Examples:
* Neptune: The farthest planet from the sun, Neptune, has an average temperature of about -214 degrees Celsius (-353 degrees Fahrenheit).
* Uranus: The second-farthest planet, Uranus, is slightly warmer but still incredibly cold, with an average temperature around -224 degrees Celsius (-371 degrees Fahrenheit).
Important Note: There can be exceptions. Some moons in the outer solar system, like Europa, exhibit signs of internal heat that could create warmer pockets beneath their icy surfaces.
