# What is the average temperature of all planets at 1 bar?

Jupiter's (and Saturn's) "surface" temperature is defined as that at 1 bar. It is inconsistent to say the other planet's surface is their hard surface. Applying the same measure what is the equivalent standard temperature of all the IAU defined planets?

• Re It is inconsistent to say the other planet's surface is their hard surface. So be it. The Sun is also a gaseous body, so it, like the giant planets, does not have a well defined surface. The Sun's "surface" is not defined in terms of pressure. It's defined in terms of whether light can escape. – David Hammen Aug 16 '20 at 13:01

At 1 bar (0.9869 atm / 14.5 psi) pressure level the planets have the following average temperatures:

• Venus: 30 degrees Celsius (1 bar level is about 33 mi or 53 km high)
• The Earth: 15 deg C
• Jupiter: minus 145 deg C
• Saturn: minus 178 deg C
• Uranus: minus 197 deg C
• Neptune: minus 200 deg C
• Titan's temperature ranges from minus 180 deg Celsius on the surface to minus 93 deg Celsius in the upper stratosphere. Titan's surface air pressure is 1.45 atm (1.47 bar).

Mercury has no atmosphere while Mars' atmosphere doesn't reach 1 bar anywhere on the planet.

• They will reach 1 bar under the surface. – user2617804 Aug 16 '20 at 7:00
• @user2617804 Mars' atmosphere doesn't reach 1 bar anywhere on its surface nor in any caverns. As far as we know it doesn't even reach the Armstrong limit (0.0618 atm). Pressure on Mars is highest in the Hellas Basin at 0.012 atm. – Giovanni Aug 16 '20 at 7:19
• For those who want to know : The Armstrong Limit on WIkipedia. – StephenG Aug 16 '20 at 15:32
• I've up voted but in Stack Exchange it's generally expected to support answers with sources. While these sound like reasonable numbers, it's impossible for future readers to tell if these are correct or just made-up random numbers. Can you add a short explanation of what sources you used and how you arrived at these values? Thanks! – uhoh Aug 16 '20 at 19:30
• @Giovanni welcome to Stack Exchange! This site works a little differently than other Q&A sites. I'll just repeat the reason(s) I've already mentioned above: "t's generally expected to support answers with sources. While these sound like reasonable numbers, it's impossible for future readers to tell if these are correct or just made-up random numbers." Without supporting sources answer has much less value, thus the change to a down vote Presumably you did have sources for these, so it mentioning them in your Stack Exchange answer should be easier & better than "take my word for it or google it" – uhoh Aug 17 '20 at 6:29