Making a comparison between Mars and Earth helps us to understand the two planets. For example, as we learn more about Mars' atmosphere we will learn more about our own Earth's atmosphere. It is believed that Mars was once like Earth with a thicker atmosphere and Mars once had surface water. Hopefully, this will help us to realize the importance of managing and conserving natural resources on Earth.

Mars is most like Earth than any other planet in the solar system. The characteristics that make Mars most like Earth are the seasons, the length of day, and the tilt of the planets' axes. The characteristics that make Mars most unlike Earth are the temperatures, the atmosphere, the ozone layer, and the gravitational field.

Characteristics	Earth	Mars
Axis Tilt	23.5°	25.2°
Seasons	4	4
Length of Day	24 hrs..	24 hrs.. 37 min.
Gravity	100%	38% of Earth's gravity
Temperature	-127° - 136° F	-194° - 72° F
Atmosphere	78% nitrogen, 21% oxygen, and other gases.	95% carbon dioxide, 0.13% oxygen, and other gases.

Click here to see more differences in detail,

and NASA's animated differences of Mars and Earth.

Now try the comparison quiz and get another stamp.

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