1. Distance from the Sun: This dictates how much solar radiation the planet receives. Planets closer to the Sun receive more energy, leading to higher surface temperatures. This is why Mercury is extremely hot and Neptune is very cold.
2. Albedo: This is the reflectivity of a planet's surface. A planet with a high albedo (like Venus, with its thick, reflective clouds) reflects more sunlight and absorbs less, resulting in lower temperatures than a planet with a low albedo (like dark, rocky Mercury).
While these two properties are the most important, other factors can also influence a planet's surface temperature, such as:
* Greenhouse effect: The presence of gases in the atmosphere that trap heat, like carbon dioxide, can significantly raise temperatures.
* Internal heat: Planets can generate their own heat through radioactive decay in their cores, which can contribute to their surface temperatures.
* Rotation: A planet's rotation can influence the distribution of heat across its surface.
However, for most planets, distance from the Sun and albedo are the dominant factors in determining their surface temperature.
