Mars: The Red Planet

Overview

Mars is the fourth planet from the Sun and is one of the most explored bodies in our solar system. It's also the only planet where we've sent rovers to roam its rocky landscape.

Description

Mars is formed around 4.5 billion years ago with a radius of 2,106 miles (3,390 kilometers). From an average distance of 142 million miles (228 million kilometers), Mars is 1.5 astronomical units away from the Sun* It takes about 13 minutes for light from the Sun to reach Mars.

Potential for Life:
Scientists don't expect to find living organisms on Mars, instead, they are focused on looking for signs of life that existed long ago, when Mars was more hospitable.

Orbit and Rotation:
Mars completes one rotation every 24.6 hours, which is very similar to a day on Earth (23.9 hours). Martian days are known as Sols. A year on Mars is 669.6 sols, or 687 Earth days. Mars' axis of rotation is tilted 25 degrees. Like Earth, Mars has distinct seasons, but they last longer on since Mars takes longer to orbit the Sun.

Structure:
Mars has an inner core at the center between 930 and 1,300 miles (1,500 to 2,100 kilometers) in radius. It's made of iron, nickel and sulfur. Surrounding the core is a mantel and above the mantel that is a crust ranging between 6 and 30 miles (10 to 50 kilometers) thick.

Temperatures:
The temperature on Mars can be as high as 20 degrees Celsius (70 degrees Fahrenheit) or as low as about -153 degrees Celsius (-225 degrees Fahrenheit).

Surface:
While Mars is about half the diameter of Earth, its surface has nearly the same area as Earth's dry land. Mars is home to the largest volcano in the solar system, Olympus Mons. It's three times taller than Mt. Everest. Mars has had a watery past, with ancient river valley networks, deltas, and lakebeds. Today, water on Mars is found in the form of water-ice just under the surface in the polar regions.

Atmosphere:
Mars has an atmosphere made up mostly of carbon dioxide, nitrogen, and argon gases. And because the atmosphere is so thin, heat from the Sun easily escapes this planet.

Magetosphere:
Mars has no magnetic field today, but some areas of Mars' crust suggests there was a magnetic field 4 billion years ago.

Moon:
Mars has two small moons, Phobos and Deimos. Phobos, the innermost and larger moon, is heavily cratered, with deep grooves on its surface. And Deimos is about half as big as Phobos and orbits two and a half times farther away from Mars.

Fun Facts!

• Humans have not yet been to Mars, but only spacecrafts and rovers.
• You could jump around three times higher on Mars than you can on Earth.
• Mars is the second smallest planet in the solar system after Mercury.
• Mars is named after the Roman god of war, Mars.

Footnotes:

*One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth.