Small World
Mars is 53% smaller than Earth.
Fourth Rock
Mars is 1.52 AU from the Sun. Earth = 1.
More Time
A Martian day is a little longer than Earth's; a Mars year is almost two Earth years.
Rocky Planet
Mars' surface has been altered by volcanoes, impacts, winds, and crustal movement.
Bring a Spacesuit
Mars' atmosphere is mostly carbon dioxide, argon, and nitrogen.
Two Moons
Phobos and Deimos are small compared to the planet.
Ringless
Mars has no rings.
Many Missions
The first success was NASA's Mariner 4 flyby in 1965,
The Search for Life
Missions are determining Mars' past and future potential for life.
The Red Planet
Iron minerals in the Martian soil oxidize, or rust, causing the soil and atmosphere to look red.
