3 ms·

Venus is the post-apocalyptic Earth you're looking for.

by idlewords 4y ago

TEP_Kim_Il_Sung 4y ago
Venus became that way because of its' oceans and no counterbalancing moon.
- shrimp_emoji 4y ago
  Nope; it's because it's closer to the Sun (whose luminosity is increasing over time, btw, so Venus got cooked more and more until it got into a critical greenhouse effect). Venus is also strange for having a retrograde (and very slow) rotation relative to other Solar System planets due to a mix of being close enough to be tidally locked to the Sun and its (now extremely thick) atmosphere creating strong thermal tides that affect its rotation. It used to be thought (and I thought this) that its retrograde rotation was due to impacts in its early history. But, in any case, having moons is unrelated.
  - moloch-hai 4y ago
    It lost (most of) its rotation because it has no moon, nothing to counter solar tides. Because it lost its rotation, it lost its magnetic field. Because it lost its magnetic field, it lost its hydrogen. Mars lost its hydrogen the same way, because its core froze enough to kill its magnetic field. There is more than one way to go. Venus is in a bad way.
  - TEP_Kim_Il_Sung 4y ago
    Yup. Oceans. Ask Anton Petrov. https://www.youtube.com/watch?v=Y_fiFzTceZc https://www.youtube.com/watch?v=Y_fiFzTceZc
justinpombrio 4y ago
Just want to clarify, in case someone reads this and thinks "like in the movies, where after the apocalypse it's barren and radioactive and very hot or cold and you can't survive outside unless you're wearing a suit". That's not what it's like on Venus. The atmosphere is made mostly of CO2. At the surface, it has a pressure of 93 times that of Earth, and temperature of 464 °C / 867 °F. This is sufficiently hot and pressurized that the atmosphere is neither a gas nor a liquid, it's a supercritical fluid. Wikipedia says that we use supercritical CO2 industrially because of how good it is at dissolving things. The record survival time for a stationary probe on the surface of Venus is 127 minutes. https://en.wikipedia.org/wiki/Venus#Physical_characteristics https://en.wikipedia.org/wiki/Venus#Physical_characteristics https://en.wikipedia.org/wiki/Supercritical_fluid https://en.wikipedia.org/wiki/Supercritical_fluid https://en.wikipedia.org/wiki/Observations_and_explorations_of_Venus https://en.wikipedia.org/wiki/Observations_and_explorations_...
- idlewords 4y ago
  Venus is also pretty cozy if you're willing to bring a blimp. At 52 kilometers, the temperature is 27 C and pressure is about half of Earth sea level. If it weren't for the sulfuric acid clouds, you could sit on a platform outside in just your shorts and an oxygen mask. Not many other places in the solar system can offer that!

Venus is the post-apocalyptic Earth you're looking for.

TEP_Kim_Il_Sung 4y ago

Venus became that way because of its' oceans and no counterbalancing moon.

shrimp_emoji 4y ago
Nope; it's because it's closer to the Sun (whose luminosity is increasing over time, btw, so Venus got cooked more and more until it got into a critical greenhouse effect). Venus is also strange for having a retrograde (and very slow) rotation relative to other Solar System planets due to a mix of being close enough to be tidally locked to the Sun and its (now extremely thick) atmosphere creating strong thermal tides that affect its rotation. It used to be thought (and I thought this) that its retrograde rotation was due to impacts in its early history. But, in any case, having moons is unrelated.
- moloch-hai 4y ago
  It lost (most of) its rotation because it has no moon, nothing to counter solar tides. Because it lost its rotation, it lost its magnetic field. Because it lost its magnetic field, it lost its hydrogen. Mars lost its hydrogen the same way, because its core froze enough to kill its magnetic field. There is more than one way to go. Venus is in a bad way.
- TEP_Kim_Il_Sung 4y ago
  Yup. Oceans. Ask Anton Petrov. https://www.youtube.com/watch?v=Y_fiFzTceZc https://www.youtube.com/watch?v=Y_fiFzTceZc

justinpombrio 4y ago

Just want to clarify, in case someone reads this and thinks "like in the movies, where after the apocalypse it's barren and radioactive and very hot or cold and you can't survive outside unless you're wearing a suit". That's not what it's like on Venus. The atmosphere is made mostly of CO2. At the surface, it has a pressure of 93 times that of Earth, and temperature of 464 °C / 867 °F. This is sufficiently hot and pressurized that the atmosphere is neither a gas nor a liquid, it's a supercritical fluid. Wikipedia says that we use supercritical CO2 industrially because of how good it is at dissolving things. The record survival time for a stationary probe on the surface of Venus is 127 minutes. https://en.wikipedia.org/wiki/Venus#Physical_characteristics https://en.wikipedia.org/wiki/Venus#Physical_characteristics https://en.wikipedia.org/wiki/Supercritical_fluid https://en.wikipedia.org/wiki/Supercritical_fluid https://en.wikipedia.org/wiki/Observations_and_explorations_of_Venus https://en.wikipedia.org/wiki/Observations_and_explorations_...

idlewords 4y ago
Venus is also pretty cozy if you're willing to bring a blimp. At 52 kilometers, the temperature is 27 C and pressure is about half of Earth sea level. If it weren't for the sulfuric acid clouds, you could sit on a platform outside in just your shorts and an oxygen mask. Not many other places in the solar system can offer that!