Mars, Our Red Neighbor
Perhaps more than any other planet in our Solar System, Mars has inspired our imagination, with many works of fiction using Mars as a central theme. Probably the most famous one being a radio play by Orson Welles, based on HG Welles’s book “War of the Worlds”, which caused quite a panic when it was first broadcasted, because many people thought it was a live broadcast of an actual invasion by Martians. Granted, this article won’t provoke such a reaction, but it might present you with a few interesting facts you haven’t been familiar with before.
Global mosaic of Mars. Cerberus region.
Although commonly thought of as being quite similiar to Earth in terms of size, Mars is actually much smaller, its diameter being two times smaller than that of Earth, measuring about 6,800 kilomteres. Its mass is much smaller as well, being only about 10% of the Earth’s mass. Martian surface gravity is about one third of Earth’s, too. As with the other solid planets, its surface has been changing through time due to volcanic activity, movement of the crust, impacts by other objects and atmospheric effects, such as dust storms, which are particularly extreme on Mars, because they can last for several months and can cover the entire planet. The seasons are extreme, too, because of the planet’s eliptical orbital path which is more elongated than those of other planets in the Solar System.
Mars has some very interesting geological characteristics, such as the largest mountain in the Solar System, Olympus Mons, which is actually a shield volcano, measuring 27 kilometers in height and approximately 600 kilometers in diameter. One of the defining characteristics of Mars is the longest and deepest canyon in the Solar System, Valles Marineris, which stretches for 4000 kilometers, and is 7 kilometers deep in some places. Mars also has two satellites, Phobos, which orbits around the planet at a distance of 9000 kilometers and has a radius of 11 kilometers, and Deimos, which orbits at a distance of 23 kilometers, and has a radius of 6 kilometers.
Pieces of Mars have fallen on Earth. Theis usually happens when an asteroid slams into a planet, causing some debris to be ejected away from the planet’s surface into space. Those ejected pieces can orbit the Solar System for millions of years before they finally crash down on some other planet. Some have crashed on Earth, and scientists have inspected them, which is how they were able to study its atmosphere before launching the first spacecraft to Mars.
Global mosaic of Mars. Visible in the center of this mosaic is the largest known chasm in the solar system, Valles Marineris.
Although its surface presents a very harsh and hostile enviroment for human beings, with extreme temperature differences and thin atmosphere, Mars has large deposits of water underneath the surface, in the form of ice, making it the prime candidate for finding life away from Earth. At this very moment, Mars is buzzing with activity, because there are three spacecrafts down on its surface, NASA’s rovers Spirit and Opportunity, and Phoenix Mars lander. Plus, there are also three spacecrafts orbiting the planet, which makes Mars the most carefully studied planet in the Solar System.