Planetary Atmospheres
Primary Atmospheric Components for the Planets
| Mercury | Venus | Earth | Mars | Jupiter | Saturn | Uranus | Neptune | Pluto | |
| Carbon Dioxide | 96% | 95.32% | |||||||
| Nitrogen | 3+% | 78% | 2.7% | Tenuous | |||||
| Oxygen | 15% | 21% | 0.13% | ||||||
| Argon | 42% | 1% | 1.6% | ||||||
| Water Vapor |
0.1% |
0.03% | |||||||
| Hydrogen | Trace | 90% | 97% | 83% | 85% | ||||
| Helium | Trace | 10% | 3% | 15% | 13% | ||||
| Methane | 2% | 2% | Tenuous | ||||||
| Neon | 0.00025% | ||||||||
| Sodium | 42% |
 |
Exploring The Planets
©2002 National Air and Space Museum