Mars

Mars is the 4th planet from the Sun. It owes its name to the Roman god of war thanks to the Romans, while the Greek named it after their god of war, Ares. Other civilizations, like the Egyptians and Chinese have named Mars in similar ways, always in connection to its red color, and it is only befitting because it has a deeply reddish color that makes it visible to the naked eye.


Characteristics


Due to the minerals rich in iron in the planet’s regolith – the dust and rock that covers the surface – Mars has a color that resembles that of bright rust. Earth’s soil resembles that of regolith, but it contains more organic content than Mars. According to scientists, the minerals in the iron oxidize, giving the planet a red color.

Mars atmosphere is cold and thin, meaning that liquid water cannot exist on its surface. It has the same amount of dry land while only being almost half the size of Earth. Mars has both the highest mountains and the deepest and longest valleys in our solar system. With 27 km, Olympus Mons is 3 times the height of Mount Everest, and Valles Marineris is a system of valleys that is 10 deep and stretches from one side to the other for 4,000 km.

Moreover, Mars has the largest volcanoes in our solar system, which includes Olympus Mons and its 600km width. It is described as a shield volcano, with slopes gradually rising like those of volcanoes in Hawaii. And just like Hawaii’s volcanoes, it was created by lava erupting and flowing for long distances before becoming solidified. Mars also has other types of volcanic forms of land, ranging from small and steep to giant plains that are covered in lava. There is still a possibility that some minor eruptions of these volcanoes might occur.

The surface of Mars is filled with valleys, channels and gullies, and it is suggested that these were formed by water flowing across the surface fairly recently. Some of these channels are 100 km wide and 2,000 km long, which suggests that water could lie in the cracks in the underground rock.

However, Mars has many regions that are flat, even low-lying plains. Its northern plains are probably the smoothest and flattest surfaces in the entire solar system, and it is suggested that these were likewise created by water flowing over the planet’s surface long ago.

Mars has a number of craters, which vary depending on the age of the surface. The southern surface is supposed to be very old, and thus has numerous craters, the largest being 2,300 km wide. This means that the northern part of Mars is younger, with fewer craters. Scientists suggest that some of the volcanoes have only a few craters, which could mean that there were eruptions of lava that covered the sites of impact. Some of those craters even look like objects have hit underground ice or water, creating deposits that could be the result of solidified mudflows.


Mars and Its Climate


As you could imagine, the climate on Mars is a lot colder than Earth’s, mostly because it is so far from the Sun. The average temperature on Mars is 60°C below zero, while temperatures close to poles can reach 125°C below zero and 20°C near the planet’s equator. The atmosphere is rich in carbon-dioxide and is 100 times less dense than that of Earth, yet it is thick enough to have weather with clouds, winds and storms. The density of the atmosphere varies with the changes in season, with winter freezing carbon-dioxide in the air.

NASA’s research has shown that Mars has snow clouds made of carbon-dioxide, which makes Mars the sole planets in our solar system that has this type of weather. In addition to this, Mars has clouds with water-ice snow falls. Apart from its cold weather, Mars also has the largest and fiercest dust storms in the entire solar system, often covering the entire planet and lasting for months on end. It is said that these storms are created by airborne dust particles that absorb sunlight, which in turn warm the atmosphere of the planet. Then these warm air pockets will flow towards cold regions, and just like on Earth, create fierce storms. These strong winds will then pick up more dust, additionally heating up the atmosphere, which then again creates stronger winds and kicks up more dust, and so on.


Characteristics of Mars’ Orbit


Similar to that of Earth, the axis of Mars is tilted in relation to the Sun, meaning that, just like Earth, Mars has seasons, with the amount of sunlight falling on certain parts of the planets varying throughout the year. But unlike on Earth, the seasons on Mars are more extreme due to the planet’s elliptical and oval orbit around the Sun being more elongated than that of other planets around the Sun. Mars has very short and very hot summers when it is closest to the Sun and the southern hemisphere being tilted towards it, and its winters are likewise very short and very cold. When Mars is farthest from the Sun and its northern hemisphere tilted towards the Sun, it has very long and mild summers, with the southern hemisphere experiencing long and cold winters.


Composition and Structure of Mars


Mars’ atmosphere consists of 95.32% carbon-dioxide, 2.7% nitrogen, 1.6& argon, 0.13% oxygen, 0.08& carbon-monoxide, with minor amounts of water, nitrogen-oxide, hydrogen-deuterium-oxygen, as well as krypton and xenon. Mars has no global magnetic field like Earth, but it has regions where the crust of the planet is magnetized up to 10 times more than anywhere on Earth, which could be proof that once it had a global magnetic field.

Scientists believe that Mars has a solid core that is composed of iron, nickel and sulfur. Mar’s mantle is similar to that of Earth, mostly being composed of peridotite, which is made of oxygen, silicon, iron and magnesium. The planet’s crust is believed to be made of volcanic rock basalt, which is common in the crusts of both the Earth and Moon. The core of the planet is thought to be 3,000 to 4,000 km in diameter, with its mantle 5,400 to 7,200 km wide, and the crust of the planet close to 50 km thick.


The Moons


Mars has 2 moons, Deimos and Phobos, which were discovered in 1877 by the American astronomer Asaph Hall, with Deimos being discovered 6 days before Phobos. Quite fittingly, the moons were named after the sons of Ares, Phobos meaning ‘fear’ and Deimos ‘rout’.

Both moons are apparently made of rock that is rich in carbon, mixed with ice and covered in loose rocks and dust. Compared to the Moon, these moons are tiny, with irregular shapes. This is due to them lacking gravity to create a more circular form. At its widest, Phobos is 27 km wide, while Deimos is 15 km wide. Both are plastered with craters from meteor impacts. Phobos’ surface has elaborate groove patterns, resembling cracks that could have been formed after an impact on it. It is a hole 10 km wide, nearly half its size. Since they have no gravity and do not rotate, they always face the same way towards Mars, just as the Earth’s Moon.


Is There Life on Mars?


As aforementioned, Mars is said to have resembled Earth a long, long time ago, and that opens up a possibility that also once contained life, with some scientists even believing there might still be some life present. Others believe that life on Earth came from Mars, or the other way round.

The most public claim by scientists that there is or was life on Mars happened on 1996 when a group of NASA scientists examined rocks that were blasted off Mars' surface and landed on Earth. These rocks are said to have contained organic molecules, a mineral called magnetite that is probably formed by some type of bacteria, but also structures that looked like fossilized microbes. Nonetheless, these claims have yet to be proven genuine and there is no real consensus whether Mars contains real signs of life.

The frozen surface of the planets suggests that at some time in the distant past the planet might have contained oceans, which would provide an ideal environment for life to develop, as it did on Earth millions, maybe billions of years ago. This could mean that, despite Mars now being a dusty planet, covered by a cold desert, it could have contained liquid water, which is supposed to be now underground, where any form of life would now exist, but it is impossible to know without better testing equipment. When the Curiosity Rover landed on Mars, it found evidence of an ancient Martian lake that could have once been teaming with life on the planet’s surface.

Earth remains full of enthusiastic and excited individuals that are eager to find out if there is life on Mars. This is further highlighted by those who are interested in objects that are spotted by landers and orbiters. Viking 1, one of two spacecrafts that were sent to Mars, returned to Earth with images of the Face on Mars in 1976. These images contained piles of rocks that resembled faces, which gave scientists reason to believe an ancient civilization inhabited Mars. These rocky formations are by far the most famous landmarks on the planets, but still, they are not real evidence that Mars used to harbor life.