Mars

Description:
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.

Radius: 3,390 km

Distance from Sun: 227.9 million km

Surface pressure: 0.636 (0.4–0.87) kPa; 0.00628 atm

Did you know: The Red Planet has a very thin atmosphere made up mostly of carbon dioxide (95.3 percent) plus nitrogen (2.7 percent), argon (1.6 percent) and traces of oxygen (0.15 percent) and water (0.03 percent).