The Planet Mars
Mars is one of the four terrestrial planets in our solar system. Our Solar system is composed of the sun, eight recognized planets, dwarf planets, interplanetary mediums, numerous small bodies called comets, asteroids and meteoroids and many other planetary satellites (Loewen & Yesh, 2008). Initially, the solar system has been studied using telescopes. However, currently, due to technological advancement, more discoveries have been made using spacecraft. This has generally provided a better understanding of the solar system. In this paper, I intend to discuss planets and further narrow down to the planet Mars.
Formation of Planets
Formation of the planets has been the heart of the scientific debate since 1755 when Emmanuel Kant hypothesized Nebular theory. In his work, he suggested that Nebulae (massive cloud of dust) and gas might have been pulled by gravity and collapsed to form a flat rotating disk (Loewen & Yesh, 2008). The flat rotating disk eventually accreted into the sun and planets. Later in 1796, Pierre Laplace contributed to Kant’s hypothesis. Laplace suggested that the rotation of nebulae resulted in centrifugal force, which led to the splitting off of clumps of matter from nebulae. These clumps of matter coalesced to form planets (Loewen & Yash, 2008).
Astronomers and scientists have refuted Nebular theory on grounds that it contradicts the observation that the sun holds a bigger mass percentage of the solar system. The theory also fails to elaborate on why Sun’s angular momentum is small. They argue that the contraction and faster rotation would have caused the Sun’s angular momentum to increase. Laplace’s contributions to the Nebular theory have been also nullified since the splitting- off of the rings of matter from nebulae would have resulted in the dispersal of particles to space and not the coalescing of rings of matter to form planets (Guillain, 2009).
Carl Von Weizsacker and Gerard Kuiper theorized the Protoplanet concept in the mid 1900s. They argued that the planet starts to appear when nebulae crumple, then the gravitational instability causes dust particles to aggregate (Guillain, 2009). The aggregation of dust particles leads to the formation of billions of planetesimals. Planetesimals then ram to create protoplanets. Meanwhile, the radiation pressure of the solar wind ousts most of the unaccredited clumps of matter. Only those protoplanets with adequate mass retained their hydrostatic shape (Guillain, 2009).
Classification and Characteristics of Planets
According to the International Astronomical Union (IAU) officials, a planet must exhibit four characteristics. First, a planet must be an astronomical body, space body or celestial body. Secondly, a planet must have sufficient mass for its own gravity. Third, a planet should roughly be spherical or have hydrostatic equilibrium. Finally, a planet must be able to clear any object around its orbit (Bell, 2012). Based on these characteristics, there are only eight recognized planets in our solar system. These include Mercury, Venus, Earth, Mars, Jupiter, Jupiter, Saturn, Uranus, and Neptune (Bell, 2012).
Terrestrial planets are also known as telluric or rocky planets. Currently, our solar system has only four terrestrial planets: Mercury, Venus, Earth, and Mars. Terrestrial planets are Earth-like planets. They are named ‘terrestrial’ because they are composed mostly of heavy silicate or iron rocks and heavy metals. They have few moons and various topological aspects such as mountains, canyons, valleys, craters and volcanoes (Loewen & Yesh, 2008). There are planets referred to as Jovian planets. Jovian planets are gaseous-giant planets. Jovian is a term derived from the giant gas planet Jupiter. For example, Jupiter’s is 318 times that of the earth. Jovian planets include Jupiter, Saturn, Uranus, and Neptune. Jovian planets have a dense core encompassed by an enormous layer of hydrogen and helium gas. These planets have a large number of moons. They turn around the sun faster than the terrestrial planets (Guillain, 2009).
What We Know about Planet Mars
The planet Mars is named after the Greek god of war (Ares). Mars was the Roman god of agriculture and provision. He was later associated with the Greek god Ares (war). Probably it got this name due to its fiery red color. For example, the Egyptian scientists called it “Her Desher” (the red one), and the ancient Chinese scientists named it “the fire star” (Loewen & Yesh, 2008).
Mars is the planet that excites scientists most of all. This is due to its possibility of sustaining life. Mars has been known since ancient times. Before the invention of telescopes, earlier scientists used their naked eyes to observe space bodies. It is through these studies and explorations that we are able to know more about this planet and its characteristics.
Galileo was the first scientist to observe Mars using a telescope. Many years after, the astronomers began sending robot spacecraft to Mars in the 1960s. The first successful spacecraft to be launched on Mars was the U.S Mariner 4 in 1965. Mariner 4 was closely followed by U.S Mariner 6 and 7 in 1969. They all disclosed that Mars cannot support life, and life never existed there before. Marine 9 was again launched in 1971 and it led to the discovery of canyons and volcanoes. Mars 2, NASA’s Viking 1 Lander were the first spacecraft to land on the red planet in 1976. The three spacecraft did not find any valid proof of life (Loewen & Yesh, 2008).
The next two spacecraft, Mars Pathfinder and Mars Global Surveyor, were launched in 1997. They were sent to analyze rocks and to show any tangible evidence of life. The U.S launched another spacecraft called Mars Odyssey in 2001. Mars Odyssey noticed water ice just below the Martian surface. It was unclear whether more water lied under the Martian surface since the craft could not probe deeper (Loewen & Yesh, 2008).
Two Mars expedition rovers called “Spirit” and “Opportunity” were sent in July 2004. Both spacecraft discovered signs of water. In 2008, NASA sent Phoenix on the Northern plains of Mars to probe more for the presence of water and the existence of life (Bell, 2012). Finally, NASA’s rover named Curiosity was sent in 2011 to study geological processes and find more on life possibilities in Mars (Bell, 2012).
Physical Characteristics of Mars
Mars is the fourth terrestrial planet. It consists of rocks rich in silicon, iron, and oxygen. Mars has an equatorial radius of about 3,396.2 km and a polar radius of about 3,376.2km. It has a volume of 1.6318 times 1011 km and a mass of 6.4185 times 1023 kg. It's the surface area is slightly lower than the total surface area of the Earth’s dry land. Mars has a higher density than Mercury. The reddish look of the Planet Mars is due to the presence of iron (III) oxide or hematite (Loewen & Yesh, 2008).
Internal Structure of the Martian Planet
The core part of Mars is approximately 1,794 ± 65 km in radius and mainly consists of iron and nickel (Guillain, 2009). The iron-nickel core of Mars to some extent is molten. This iron-nickel core is enclosed by a silicate mantle that is responsible for the tectonic and volcanic aspects of the rocks on the planet. The Martian crust is mainly composed of iron, magnesium, aluminum, calcium and potassium elements. The Martian crust has a thickness that ranges from about 50 to 125 km (Guillain, 2009).
Geological Structure of Mars
The Martian planet has the same amount of dry land as that of the planet Earth. This rocky planet is believed to contain the highest mountain (Olympus Mons) and the deepest, longest valley in our Solar system. Olympus Mons is about 27 km high, about three times higher than Mount Everest. The deepest and longest valley is known as Valles Marineris (Loewen & Yesh, 2008).
Channels, valleys, and gullies are believed to have been the pathways for liquid water in recent times. In addition, many regions of Mars are just flat and low-lying plains. The Northern plains of the Martian planet are classified as flattest in our solar system (Loewen & Yesh, 2008).
In terms of climate, scientists incline to the opinion that Mars is colder than the planet Earth. The average temperature for Mars is around -80 degrees Freight or -60 degrees Celsius (Bell, 2012).
Atmospheric Composition of Planet Mars
The atmospheric composition of the Martian planet is Carbon (IV) oxide 95.32 %, Nitrogen 2.7 %, argon 1.6 %, oxygen 0.13 % and Carbon (II) 0.08 %. In addition, Mars’ atmosphere is composed of smaller amounts of water, nitrogen oxide, krypton and xenon (Loewen & Yesh, 2008).
The Magnetic Field of Mars
The Martian planet, so far, has no global magnetic field, although, there are some parts of its crust that can be strongly magnetized than any other substance on Earth (Loewen & Yesh, 2008).
Hydrology of Mars
The two polar ice caps (North polar early summer and south polar Midsummer) found on this planet appear to be formed of ice water. Large quantities of water ice are believed to be trapped inside the planet’s thick cryosphere (Loewen & Yesh, 2008). However, due to low atmospheric pressure and temperature, liquid water cannot exist on the Martian planet surface.
The Moons of the Mars
The red planet has two moons. These are Phobos and Deimos. The two moons were discovered in 1877 by Asaph Hall, an American astronomer (Loewen & Yesh, 2008). Phobos and Deimos are composed of carbon-rich rock and ice water. The two moons are covered in dust and loosely parked rocks. They are irregular in shape because they lack enough gravity to aggregate them into a hemispherical shape. Both Phobos and Deimos get wider to about 27 km and 15 km respectively (Loewen & Yesh, 2008).
Phobos is always spinning towards Mars each century. It is predicted that, in the next 50 million years, Phobos will crash into Mars forming a ring of debris around the red planet (Bell, 2012).
Possibility of Life
This is the most interesting part. Most scientists and researchers have speculated that the planet Mars had once supported life. They say there is the possibility that men were living on the planet Mars. In 1996, David McKay and his research colleagues claimed that rocks on Mars’ surface blasted out onto the Earth through cosmic forces (Guillain, 2009). Within these rocks are multifaceted organic molecules, grains of magnetite that can form some bacteria and small structures that bear a resemblance to microbes (Bell, 2012). The claim has not gotten any proof since it was made. Therefore, it cannot be used to conclude that life might have existed on Mars.
In conclusion, the scientific explorations that have been conducted about the planet Mars have revealed a lot of exciting findings. These findings have raised the interest of scientists to explore, through space technology, the ability of this planet to sustain life. There are findings that Mars might have harbored water in oceans and seas because of the presence of craters and valleys. The presence of water might have provided good conditions for life to exist. Though Mars is cold, it is believed life can still exist beneath it.