Type of Planet
Mars is a terrestrial planet, meaning primarily composed of rock and metal.
A fine dust covers the surface of Mars. Beneath the layer of dust, the Martian crust consists mostly of volcanic rock.
Mars is known as the "Red Planet" because of its reddish appearance caused by the iron in its soil.
Size (Diameter), Mass, and Density
Second-smallest planet in the Solar System after Mercury. Around half the size of Earth and 10 percent of its mass.
The density of Mars is 3.93 grams per cubic centimeter, compared to Earth's 5.51.
As Mars is smaller, has less mass, and density, than the Earth, it also has less gravity. Mars has 38 percent of the Earth's gravity.
Unlike the Earth, Mars has no global magnetic field. Mars does have a magnetic field but it is less extensive than that of the Earth.
Without a spinning, molten core, Mars is unable to generate a global magnetic field.
The atmosphere of Mars is about 100 times thinner than Earth's, too thin to easily support life as we know it.
It is 95 percent carbon dioxide, and the air can become very dusty. Giant dust storms can blanket the entire planet for months.
The daytime temperature on Mars in summer can reach 20 degrees celsius (near the equator), but the nighttime temperature can plummet to minus 73 degrees celsius.
The Martian atmosphere contains greenhouse gases. This would cause a much warmer temperature if the planet had the gravity and magnetic field that would allow it to hold onto gases.
Length of a Day (Rotation)
A day on Mars lasts 24 hours 37 minutes.
Mars has an axial tilt of 25 degrees, very similar to Earth. This gives Mars seasons, just like the Earth.
Length of a Year (Orbit)
A year on Mars lasts 687 Earth days.
Distance from the Sun
Mars is the fourth planet from the Sun at 142 million miles.