Solar System Planets

“If we knew exactly what to expect throughout the Solar System, we would have no reason to explore it” Anderson, P., (n.d.). There are eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The first four planets are known as terrestrial planets. The terrestrial planets are the inner planets closest to the Sun. The terrestrial planets of Mercury, Venus and Mars are very similar in structure and composition to the planet Earth. All terrestrial planets have approximately the same type of structure. They contain a central metallic core composed of mostly iron, with a surrounding silicate mantle. These planets have similar landscape features such as canyons, mountains, craters, and volcanoes. 

Mercury is the closest planet to the Sun and is the smallest terrestrial planet in the solar system. Mercury’s thin atmosphere creates an environment ranging between burning and freezing conditions. Mercury’s temperature reaches to be a blazing 800 degrees Fahrenheit during the day and may drop to a frigid minus 290 degrees Fahrenheit during the night. Mercury is composed of mostly iron and nickel with an iron core. Unlike Earth, this planet does not have a moon. Mercury’s spin rotation is considerable slower than Earth’s. It spins one time in 60 Earth days. Due to the close proximity to the sun, it is impossible for any type of life as we know it to survive on Mercury.

Venus is about the same size as Earth. The atmosphere on Venus is dominated by a thick, toxic carbon-monoxide which traps heat. The thick atmosphere of Venus has acted as a shield from meteors; underneath the thick clouds, the surface of Venus is smooth. Venus is the second planet from the Sun, however, it is the hottest planet in the solar system. Venus, like Mercury, does not have a moon. The planet’s surface consists of volcanoes and deep canyons. Research, from geologists, suggest that some of the volcanoes on Venus are active. It is very windy on Venus which keep the clouds in constant motion. Even though the planet spins slowly, about once every 243 Earth days, the clouds move around 224 mph. The orbit of Venus is closest to Earth’s orbit and both atmospheres have clouds. However, unlike Earth’s clouds, the clouds on Venus are poisonous because they are made up of sulfuric acid. The temperature in Venus reaches to blazing 870 degrees Fahrenheit. “The surface of Venus is hot enough to melt lead” Reed (2012). Life on Venus is impossible due to the toxic atmosphere, extreme heat, deep canyons, and active volcanoes. 

Earth is the third planet from the Sun and it is the largest planet of the terrestrial planets. Earth is the only planet known that has water on its surface. In fact, 70% of the Earth’s surface is covered by water. Earth’s atmosphere is a combination of nitrogen and oxygen, making it possible for humans and animals to breath. Like all other terrestrial planets, the Earth’s structure is made up of layers. The Earth has a core, mantle and a crust. The core is made up two parts. The solid, inner core consists of iron and the outer core is composed of a nickel-iron alloy. The mantle is composed of rocks that are rich in magnesium and iron. The Earth’s crust consists of elements such as: oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium. Sharp (2017). The Earth’s crust is divided into plates that float on the mantle. These plates are in constant motion; when the plates grind together it can result in earthquakes and volcanic activity. Mountains are formed when the plates collide. When one plate slides under another plate, trenches are formed. The theory of Plate tectonics explains the motion of these plates. The surface of the Earth varies depending on the location. The surface has deep valleys, canyons, mountains, rolling hills, deserts and plateaus. The temperature on Earth depends on the time of day, time of year, and the location in which the temperature is being measured. Most areas on Earth experience four seasons; Spring, Summer, Fall, and Winter. However, that is not the case everywhere, it depends on the location on the planet. “Earth is the only place in the universe confirmed to host life” (Greshko, n.d.).

The planet Mars is the fourth planet from the Sun. “Mars is one of the most explored bodies in our solar system, and it’s the only planet where we’ve sent rovers to roam the alien landscape” (“Mars, The Red Planet”, n.d.). Mars is often referred to as The Red Planet, due to the iron minerals in the soil oxidizing causing the soil and atmosphere to appear red. The core of the planet is similar to Earth’s, but its exact structure is unknown. The climate on Mars is a cold, dusty desert. Mars has a very thin atmosphere consisting of mostly carbon dioxide. Mars has very little oxygen or water vapor. Mars is a rocky planet due to the surface being altered due to volcanoes and high winds. The planet Mars is half the size of Earth. Unlike Earth, Mars has two moons named Phobos and Deimos. A year in Mars is equivalent to 1.88 Earth years. This makes the seasons on Mars much different than the seasons on Earth. For example, Mars has about seven months of spring, six months of summer, around five months of fall, and four months of winter. During the warmer months, the temperature on Mars may get up to 70 degrees Fahrenheit, but at night the temperature drops to be about minus 100 degrees Fahrenheit. In other months, the average temperature is minus 80 degrees Fahrenheit and in the winter months the temperature drops to minus 195 degrees Fahrenheit. The planet cannot retain any heat due to its thin atmosphere. Despite all the research and plans to travel to or live on Mars, as of right now, impossible to do those things. The planet is too hostile and survival would not be possible.

People may wonder what is the point of having different planets if there can only be life on one of them. The planets do serve a purpose, even though they don’t support life. Those planets help protect the Earth by serving as shields against comets, asteroids and meteorites that could destroy the Earth. Earth is the only planet that supports life. “This most beautiful system of the sun, planets and comets, could only proceed from the counsel and dominion of an intelligent and powerful Being” (Newton n.d.).

References

1. All About Earth. (n.d.). Retrieved from http://spaceplace.nasa.gov/all-about-earth/en/
2. Anderson, P. (n.d.). Solar Sayings and Quotes. Retrieved from http://www.wiseoldsayings.com/solar-quotes
3. Futurism Staff. (2016). Is Life on Mars Possible? Retrieved from http://futurism.media/is-life-on-mars-possible
4. Gammon, K. (2019). Terristrial Planets: Definition & Facts About the Inner Planets. Retrieved from http://www.space.com/17028-terrestrial-planets.html
5. Greshko, M. (n.d.). Planet Earth, Explained. unknown: National Geographic. Retrieved from http://www.nationalgeographic.com/science/space/solar-system/earth/
6. Mars, The Red Planet. (n.d.). Retrieved from http://www.solarsystem.nasa.gov/planets/mars/overview
7. Newton, I. (n.d.). Goodreads. Retrieved from http://www.goodreads.com
8. Reed, N. T. (2012). What is Venus Made Of? Retrieved from http://www.space.com
9. Sharp, T. (2017). What is Earth Made Of? Retrieved from http://www.space.com

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