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The Earth isn't a closed system. Most of the heat that is getting trapped by C02 is coming from the sun, and we continually bleed atmosphere into space. The ave

The Earth isn't a closed system. Most of the heat that is getting trapped by C02 is coming from the sun, and we continually bleed atmosphere into space. The average temp of the universe is -455F, so cold is the most abundant resource.

epolanski 3y ago
Technically speaking I don't think you can measure the "temperature of the universe". Temperature depends on the kinetic energy of a certain amount of whatever molecules, but the universe is essentially empty/void, thus there's nothing really to measure the temperature of. I know that it isn't strictly empty/void, but for a temperature related measurement it essentially is.
- roywiggins 3y ago
  https://bigthink.com/starts-with-a-bang/universe-temperature/ https://bigthink.com/starts-with-a-bang/universe-temperature... > in the deepest depths of intergalactic space — an object placed there would gain or lose energy until it reached the background temperature of that light left over from the Big Bang: 2.725 K.
  - mrguyorama 3y ago
    While true, it would take a very very long time. There simply are not enough molecules of anything in "space" to effectively and efficiently transport heat, and we even struggle to keep craft in space cool because the only reliable source of heat transfer is black body radiation from your craft. The heat capacity of space is nearly non-existent.
  - epolanski 3y ago
    There's a problem with that: there's really nothing much to transfer heat to in the universe's voidness, thus the heat dissipation would be insanely slow.
- quchen 3y ago
  To add to the other comment mentioning the cosmic microwave background, consider that thermometers measure _their own_ temperature, not the one of their surroundings. This nitpick is actually important here, because it explains how temperature can be measured even in complete (massive+free particle) vacuum. Whenever there is energy transfer into the thermometer, and the CMB does just that, you measure temperature. Related fun fact: the vacuum of space is not only very very cold, but also very insulating. Space suits have to be fitted with a cooling system, otherwise the heat of the astronaut's body and suit electronics would become too warm, even though it's 2.7K all around them.

epolanski 3y ago

Technically speaking I don't think you can measure the "temperature of the universe". Temperature depends on the kinetic energy of a certain amount of whatever molecules, but the universe is essentially empty/void, thus there's nothing really to measure the temperature of. I know that it isn't strictly empty/void, but for a temperature related measurement it essentially is.

roywiggins 3y ago
https://bigthink.com/starts-with-a-bang/universe-temperature/ https://bigthink.com/starts-with-a-bang/universe-temperature... > in the deepest depths of intergalactic space — an object placed there would gain or lose energy until it reached the background temperature of that light left over from the Big Bang: 2.725 K.
- mrguyorama 3y ago
  While true, it would take a very very long time. There simply are not enough molecules of anything in "space" to effectively and efficiently transport heat, and we even struggle to keep craft in space cool because the only reliable source of heat transfer is black body radiation from your craft. The heat capacity of space is nearly non-existent.
- epolanski 3y ago
  There's a problem with that: there's really nothing much to transfer heat to in the universe's voidness, thus the heat dissipation would be insanely slow.
quchen 3y ago
To add to the other comment mentioning the cosmic microwave background, consider that thermometers measure _their own_ temperature, not the one of their surroundings. This nitpick is actually important here, because it explains how temperature can be measured even in complete (massive+free particle) vacuum. Whenever there is energy transfer into the thermometer, and the CMB does just that, you measure temperature. Related fun fact: the vacuum of space is not only very very cold, but also very insulating. Space suits have to be fitted with a cooling system, otherwise the heat of the astronaut's body and suit electronics would become too warm, even though it's 2.7K all around them.