Ask Astro: How hot would Venus be at different distances from the Sun?

A: Venus, with an average surface temperature of around 863 degrees Fahrenheit (462 degrees Celsius), is the hottest planet in our solar system, even though Mercury is closer to the Sun. This is because the impact of a runaway greenhouse affected the planet, causing the pressure of the atmosphere to reach about 92 times greater than the Earth’s surface. On Venus, lead melts like butter.

The position of a planet also affects surface temperature because the amount of sunlight a planet receives receives in square proportion to its distance from the Sun. In other words, the farther a planet is from the Sun, the less radiation it will receive.

At its orbital speed, Venus receives nearly twice as much energy from the Sun as Earth. However, at Mercury’s speed, it would receive about 6.5 times as much energy, producing an average surface temperature approaching 1,340 F (727 C). That’s even hotter than the real Venus! Alternatively, if we had altered the Earth with Venus, the surface of our sister planet would have been slightly above 440 F (227 C) on average, like in a very hot oven.

Venus cools even more as it moves further away from the Sun. At Mars, which receives 43 percent less energy from the Sun than Earth, Venus would have an average surface temperature of about 44 F (7 C). That’s just a bit colder than the average average temperature of 59 F (15 C). If Venus were to move to the orbit of Jupiter, sunlight would be less than 4 percent that of Earth, and the planet’s surface temperature would be closer to –82 F (–63 C). At these temperatures, no surface water would be present except as ice. (However, Venus seems to have lost any of its surface water in that ancient greenhouse effect.) Beyond Jupiter’s orbit, the temperature on Venus would reach –280 F (–173 C ) and perhaps even colder near the farthest edges of our solar system. Thus, even Venus can grow cold if it is located far enough away from the sun.

Ramses Ramirez