| Venus | Earth without life (Calculated as an interpolation between Venus and Mars, including the chemical differences in the planets) |
Mars | Earth with life | |
| Carbon dioxide |
96,5%
|
98%
|
95%
|
0,03%
|
| Nitrogen gas |
3,5%
|
1,9%
|
2,7%
|
79%
|
| Oxygen gas |
traces
|
0,0%
|
0,13%
|
21%
|
| Methane gas |
0,0
|
0,0
|
0,0
|
1,7 ppm
|
| Temperature at surface |
459°
|
240° - 340°
|
- 53°
|
16°
|
| Pressure at surface (bar) |
90
|
60
|
0,0064
|
1,0
|
Adapted from: Lovelock, J., 1988. The ages of Gaia. Norton & Company, New York, London.