Mars is the fourth planet from the sun, and it’s also known as the Red Planet because of its blood-red appearance. It’s been a target for space exploration since hundreds of years.
Its thin atmosphere is mostly made of carbon dioxide, argon, and nitrogen, with a small amount of oxygen and water vapor. Its surface features are similar to those of the Moon, with valleys, deserts and polar ice caps.
1. It’s the fourth planet from the sun
Mars is the fourth planet from the sun and the second smallest planet in the solar system. It has surface features resembling those of the moon and Earth, including mountain ranges, volcanic fields, valleys, ice caps, canyons, and deserts.
Its red color comes from a high amount of iron oxide on its surface. It also has two tiny, potato-shaped moons called Phobos and Deimos.
The Martian atmosphere is made of argon, nitrogen, carbon dioxide, and oxygen. The planet’s central core is between 930 and 1,300 miles (1.5 to 2,100 kilometers) thick, with a rocky mantle and crust above it.
Scientists have found many interesting things on the Red Planet, from volcanoes to polar ice caps to impact craters. Its surface is covered with iron oxide, making it red and giving it the name “the red planet.”
Since at least the 19th century, scientists have speculated that intelligent life might exist on Mars. These speculations stemmed from the discovery of complex systems of straight lines on its surface that astronomers believed were artificial canals for water irrigation.
However, more advanced telescopes and observations on the surface have proven that these lines are simply an optical illusion. As a result, no one has found evidence of life on Mars.
The Red Planet’s climate is a mystery, too. The axis of its rotation is tilted, which means that the amount of sunlight it receives can vary greatly during different times of the year. This results in short, warm summers for the northern hemisphere and long, cold winters for the southern hemisphere.
Mars’s unique position in the solar system and its unpredictable orbit around the Sun have caused its climatic conditions to change significantly throughout its history. Its icy, nitrogen-rich atmosphere was once home to living organisms, but these creatures became extinct about 3 billion years ago. In addition, asteroid impacts altered its atmosphere. This caused a new, cold age on the planet that led to a thick layer of snow covering much of its surface.
2. It’s the largest planet in the solar system
Mars is the largest planet in the solar system and is about 4.5 billion years old. Like other planets, it formed from a cloud of dust and gas. It is composed primarily of rock and metal, has a 24-hour day, and probably had large amounts of water on its surface in the distant past.
The name ‘Red Planet’ comes from its bright red color, caused by iron oxide in the Martian soil called regolith. It is also home to the tallest mountain/volcano in the Solar System, Olympus Mons and the biggest canyon Valles Marineris which is 4,000 miles long.
Because of its size and distance from the Sun, it is very cold. Its atmosphere is only a thin blanket of gases, and over millions of years the Sun has stripped away a fraction of its carbon dioxide and water, leaving the planet’s temperature 100 times lower than that on Earth.
Scientists have also found evidence that liquid water once flowed on the Martian surface and may be hiding inside underground rock. The evidence is scattered across the planet’s surface in features such as giant volcanoes, canyons, dry river beds and craters created by meteorites.
However, because of its low atmospheric pressure, liquid water can only exist on the surface at elevations lower than a few hundred feet. As it is too cold for liquid water to remain in the atmosphere, it is unlikely that life will ever arise on Mars.
The planet has two moons – Phobos and Deimos – which were discovered 151 years after they were written about in Jonathan Swift’s book “Gulliver’s Travels”. It is estimated that Phobos will crash into Mars at some point in the future.
3. It’s the only planet with two moons
Mars is the only planet in our solar system with two natural satellites, Phobos and Deimos. These irregularly shaped, rocky moons were discovered by astronomer Asaph Hall in 1877 and named for the Latin words phobos meaning fear and deimos meaning terror or flight.
They are among the smallest natural satellites in our solar system and may have formed from an impact. There are three possible ways that a planet can acquire a moon:
The first way is when material from a circumplanetary disk accrues around a proto-star, breaking up into small planetesimals. This is the most common scenario for gas giants such as Jupiter or Saturn, and most of their moons come from this process.
Another option is when a planet is born from a violent collision with another object, such as an asteroid or a rogue comet. This would have produced a lot of debris, including some small moons like ours.
Still, no combination of these parameters can yield a set of orbits similar to the one we see for Mars’ moons. Instead, it appears that the moons were created in an extended disc of debris, possibly from a giant impact.
Scientists have used computer simulations to study how this impact could have generated a disc of debris that accreted into the two moons we now see orbiting Mars. They found that the impact was too powerful to produce a single large moon, but it might have produced two small ones, similar to those we see around Mars today.
4. It’s the only planet with a volcano
Mars has a lot of interesting things, but one thing that many people don’t realize is that it also has a volcano. This is a unique feature of the planet, and it is something that we don’t have on other worlds in our solar system.
Volcanic eruptions occur when a planet’s surface is heated by the rise of a plume of heated rock from deep within its crust. These plumes can then flow out and create massive shield volcanoes or a number of other kinds of volcanic landforms.
Some of the largest shield volcanoes in the solar system are on Mars, including Olympus Mons which is 370 miles (600 km) wide and has a slope that rises gradually like a Hawaiian volcano. There are also some smaller shields and cones on the planet, along with a number of other different kinds of volcanic landforms.
The age of Mars’s volcanoes varies, but most of the highland paterae and mare-like plains erupted about 3 billion years ago, while giant shield volcanoes formed only 2 billion years ago. Some of the youngest lava flows on Olympus Mons are only 20 to 200 million years old.
Because of the lower gravity on Mars, lava flows and ash thrown from explosive eruptions travel farther than they do on Earth. This makes it hard to determine the exact ages of these flows, but scientists can use the number of impact craters that are seen on them to estimate their age.
The lava on Olympus Mons may have been formed just recently, but the impact craters are very old, suggesting that they occurred very long ago. If the new findings are confirmed, this could mean that the volcano was still active in its early days.
5. It’s the only planet with a polar cap
Until recently, it was believed that the polar caps on mars primarily consisted of frozen water ice, but now scientists have discovered that these caps are a mix of carbon dioxide and dry ice.
The north polar cap on Mars is about 621 miles (1000 kilometers) in diameter and 1,2 miles (2 km) deep, making it one of the largest ice caps in the solar system. The bottom layer of the north polar cap is made of water ice.
This ice cap, which has been examined by multiple Mars orbiters, has also revealed a layer of dry ice that forms a thin sheath over the top. This layer is only about one meter (three feet) thick in the north and eight meters (26 feet) thick in the south.
In the summer, when the temperature on mars is much higher, this dry ice sublimates to gas, forming a much thinner layer of carbon dioxide that floats above the surface. In the winter, the polar cap becomes thicker, extending down to latitude 50 degrees.
Researchers from the University of Cambridge have used laser altimeter data taken by NASA’s Mars Global Surveyor satellite to map the icy layers on the upper surface of the northern cap. These images reveal subtle differences in shape and steepness that indicate that sub-surface lakes are present beneath the cap.
Another study found that a radar instrument on ESA’s Mars Express spacecraft detected an area under the southern polar cap that strongly reflected radar signals. It was interpreted as a lake, but new research suggests that it may actually be made of clays or metal-bearing minerals.