Many people know that most of the planets in our Solar System have extreme temperatures unsuitable for supporting life. What exactly are the temperatures on the surface of these planets though?
Mercury is the planet closest to the Sun, so one would assume that it is a burning furnace. While the temperature on Mercury can reach 465°C, it can also drop to frigid temperatures of -184°C. There is such a big variation in Mercury’s temperature because the planet has no atmosphere, and it spends relatively slowly compared to some of the other planets.
Venus, the second closest plant to the Sun, has the highest average temperatures of any planet in our Solar System, regularly reaching temperatures over 460°C. Venus is so hot because of its proximity to the Sun and its thick atmosphere. Venus’ atmosphere is composed of thick clouds containing carbon dioxide and sulfur dioxide. This creates a strong greenhouse effect, trapping the Sun’s heat in the atmosphere and turning the planet into a furnace.
Earth is the third planet from the Sun, and so far the only planet known capable of supporting life. The average temperature on Earth is 7.2°C, but it varies much more than that at its extremes. The hottest temperature ever recorded on Earth was 70.7°C in Iran. The lowest temperature was -89.2°C in Antarctica.
Mars is cold because does not have an atmosphere to retain heat and it is relatively far from the Sun. Because Mars has an eccentric orbit around the Sun – it gets much closer at some points than at others – its temperatures can vary by as much as 30°C during the summer in the northern and southern hemispheres. The minimum temperature on Mars is approximately -140°C, and the highest is 20°C.
Jupiter has no solid surface, since it is a gas giant, so it has no surface temperature. At the top of Jupiter’s clouds, the temperature is around -145°C. As you descend closer to the center of the planet, the temperature increases. At the point where atmospheric pressure is ten times greater than it is on Earth, the temperature is 21°C, which scientists call “room temperature.” At the core of the planet, the temperature is much higher, reaching approximately 24,000°C at the core. As a comparison, the core of Jupiter is hotter than the surface of the Sun is.
Because of Saturn’s tilt, the southern and northern hemispheres are heated differently causing seasonal and temperature changes. Like on Jupiter, the temperature in the upper atmosphere of Saturn is cold – up to approximately -175°C – and increases closer to the center of the planet.
Uranus is the coldest planet with a lowest recorded temperature of -224°C. Although Uranus is far from the Sun, that is not the only reason why it is so cold. All of the other gas giants in our Solar System give off more heat from their cores than they receive from the Sun. Uranus has a core of approximately 4,737°C, which is only one-fifth the temperature of Jupiter’s core.
With temperatures dropping to -218°C in Neptune’s upper atmosphere, the planet is one of the coldest in our Solar System. Like all of the gas giants, Neptune has a much hotter core, which is around 7,000°C.