Mars has been a mysterious planet to astronomers for centuries. It’s always been thought to be moonless but in 1877 astronomer Asaph Hall discovered two natural satellites called Deimos and Phobos.
These were the first observations of a planet outside our solar system. Over time, more and more discoveries have helped to change our understanding of the planet.
What is Mars?
Mars is a planet in the solar system that formed 4.5 billion years ago when the Sun pulled swirling gas and dust into its orbit. It’s about half the size of Earth and has a rocky core, a mantle, and a solid crust.
Mars has a thin atmosphere that consists of carbon dioxide. This is because Mars doesn’t have a magnetic field, which makes it easier for the Sun’s high-energy particles to strip away its atmosphere.
Because of this, the surface of Mars is very dry and cold. It receives less than half as much sunlight as Earth.
How did it get there?
In the early days of the Solar System, the Sun was just a giant rotating ball of gas and dust. Some of that gas merged with other swirling particles to form the first planets.
Mars is a relatively young planet, formed about 4 billion years ago in the same chaotic period as our own Solar System. During this time, it was heavily bombarded by meteors, which ripped the planet’s crust away and created craters all over its surface.
This tumultuous period of Martian history helped shape the planet we know today. But it also left a lot of mysteries unanswered.
One mystery is how Mars was able to create a thick atmosphere, which shields the planet from solar winds. Another is how Mars’ surface temperature fluctuates. The planet can be as cold as -225 degrees Fahrenheit (-153 degrees Celsius) in the winter and warm as 70 degrees F (20 degrees C) in the summer.
What is life like on Mars?
Mars is a rocky planet that orbits the same star as Earth. Like Earth, it has a thick atmosphere and liquid water on its surface.
But just about four billion years ago, Mars turned from a habitable world to a dead wasteland. As its atmosphere thinned and the sun’s rays stripped away the planet’s water, it became cold and dry.
That meant early microbes on Mars, which produce methane gas, would have had to find another source of energy. Fortunately, hydrogen is abundant in the Red Planet’s atmosphere and could have provided that fuel.
What are the chances of finding life on Mars?
One of the great mysteries of the universe is whether life originated on another planet. If so, it would have evolved in ways that are quite unlike those on Earth.
For a billion years, Mars was a warm, wet planet with an atmosphere that produced gases that contain the building blocks of organic chemistry. Meteor impacts that hit the planet during those early days could have sent gases with the right chemical composition into Mars’s atmosphere, creating the conditions necessary for life to take hold.
Scientists have long wondered if Martian microbes might survive beneath the surface. But current technologies don’t have the ability to drill deep enough to find them.