Planetary Temperature Calculator
Calculate equilibrium temperature of planets
About this calculator
The Planetary Temperature Calculator determines the equilibrium temperature of planets based on their distance from their host star and the star's luminosity. This tool uses the Stefan-Boltzmann law and energy balance principles to calculate the theoretical temperature a planet would reach when energy absorbed from stellar radiation equals energy radiated back to space. It's essential for astronomers, students, and researchers studying planetary science, exoplanet habitability, and climate modeling to understand how stellar proximity affects planetary temperatures.
How to use
Enter the planet's distance from its star (in astronomical units or kilometers) and the star's luminosity (relative to the Sun or in watts). Optionally, input the planet's albedo (reflectivity) to account for how much sunlight is reflected. Click calculate to get the equilibrium temperature in Kelvin, Celsius, or Fahrenheit.
Frequently asked questions
What is planetary equilibrium temperature?
It's the theoretical temperature a planet reaches when incoming solar energy balances outgoing thermal radiation, assuming no atmospheric effects.
Why doesn't this match actual planetary temperatures?
Real planets have atmospheres, greenhouse effects, internal heating, and varying surface properties that significantly alter temperatures from equilibrium calculations.
What is albedo and how does it affect temperature?
Albedo is the fraction of sunlight reflected by a planet's surface. Higher albedo means more reflection and lower temperatures.