Timeline for Is the fact that 100 kPa equals about 1 atmosphere accidental?
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Sep 1, 2017 at 0:57 | comment | added | user2617804 | That reference is for only the atmosphere 2.7 billion years ago. For the eras of the dinosaurs, it makes a lot more sense if the atmosphere was a lot higher pressure. | |
| Aug 31, 2017 at 21:09 | comment | added | Hagen von Eitzen | Hm, you should express the Venus athmosphere pressure in terms of Venus-Pascals, i.e., density of the most prevalent liquid, radius of the planet, length of a venusian day | |
| Aug 30, 2017 at 23:57 | history | edited | Sean E. Lake | CC BY-SA 3.0 |
Add reference to atmospheric pressure reconstruction.
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| Aug 30, 2017 at 23:26 | comment | added | Sean E. Lake | Actually, that definition of the meter just piles on more coincidences, including two more factors of $R_{\mathrm{Earth}}$, two factors of $M_{\mathrm{Earth}}$, and two factors of $G$. | |
| Aug 30, 2017 at 22:41 | comment | added | Sean E. Lake | @JeppeStigNielsen Interesting. That would remove one of the coincidences, and pressure is more tightly tied to $g$ than any of the other quantities mentioned. I think that the temperature coincidence can't be avoided, though it can be argued that temperature and pressure near water's triple point is essential for life, but that leaves a wide range of pressures, as this graph shows. | |
| Aug 30, 2017 at 22:35 | comment | added | Jeppe Stig Nielsen | Originally, they wanted to define the meter from the length of the seconds pendulum. So that would mean $1\operatorname{m} \equiv g \left(\frac{1\operatorname{s}}{\pi}\right) ^2$ where $g$ is the standard gravity. You can write your answer again using that definition of the meter. The fact that the old definition with the seconds pendulum gives $0.994$ times the other definition with the North-Pole-to-Equator distance, must be another coincidence. I think they changed to the latter definition because $0.994$ is so close to $1$. | |
| Aug 30, 2017 at 22:08 | comment | added | Sean E. Lake | I have asked a question over at the Earth Science StackExchange for a paleoclimate reconstruction of the Earth's atmospheric pressure at sea level. earthscience.stackexchange.com/questions/12186/… | |
| Aug 30, 2017 at 21:26 | history | answered | Sean E. Lake | CC BY-SA 3.0 |
