How Many Travelers Are There in Space?
Currently, four planets in the Solar System (Earth, Mars, Venus and Mercury) and Pluto, which is considered a dwarf planet, are planets with a known atmosphere and surface. Apart from these, some other moons such as Jupiter’s moon Europa and Saturn’s moon Enceladus are thought to have liquid water under the glaciers. For this reason, these moons also show planetary features, although they don’t exactly fit the definition of “planet”.
Outside the Solar System, thousands of planetary candidates have been discovered so far, and these are exoplanets with “planetary” status. Many of these exoplanets may have similar or different characteristics to Earth.
However, scientists struggle to pinpoint exactly how many “planets” exist outside the Solar System because detecting planets in distant star systems is a challenging task and it is not possible to detect all exoplanets with current technologies.
Therefore, the number of planets currently discovered and known is constantly increasing, and more planets are expected to be discovered as more research and observations are made.
World:
Earth is the third planet in the Solar System and has an important position as the only known planet inhabited by humans. Here are some key features about Earth:
Size and Position: Earth is one of the inner planets closest to the Sun. The Earth, which is approximately 12,742 kilometers in diameter, is located at an average distance of 149.6 million kilometers from the Sun. Earth requires approximately 365.25 days (one year) to complete one year around the Sun.
Atmosphere: The Earth is surrounded by a layer of gas called the atmosphere. The atmosphere contains oxygen, nitrogen, carbon dioxide and other gases that allow living things to survive. The atmosphere also protects the planet from harmful radiation from the sun’s rays.
Water: Approximately 71% of the Earth’s surface is covered with water. This body of water consists of oceans, seas, lakes, rivers and glaciers. Water is of vital importance for the survival of living things and is an important feature that distinguishes the Earth from other planets.
Life: There is a wide biodiversity on Earth. Plants, animals, microorganisms and other creatures live in different ecosystems of the Earth. Earth’s living conditions depend on factors such as water, the appropriate temperature range, and the composition of the atmosphere.
Earth’s crust: The crust, the outer layer of the Earth, includes landmasses, ocean floors, and mountain systems. The earth’s crust is divided into large pieces called tectonic plates, and the movements of these plates also cause earthquakes and volcanic activities.
Climate and Weather: The world has various climatic zones. Climate describes its general atmospheric conditions, including long-term weather conditions and seasons. Temperature, precipitation, winds and other weather conditions affect climate in different parts of the world.
Geological Activity: The Earth has an active geological structure. Thanks to plate tectonics, movements occur constantly in the earth’s crust. These movements cause volcanic activities, mountain formations, earthquakes and continental drift. There is also a hot core and layers of molten magma in the Earth’s interior.
Magnetic Field: The Earth has a magnetic field originating from its core. This magnetic field protects the Earth by preventing charged particles from the Sun from entering the atmosphere. It also enables the use of tools such as magnetic compass.
Moon and Sun Interaction: The largest natural satellite of the Earth is the Moon. The gravitational pull of the Moon causes tides in the seas. In addition, the positions of the Moon and Sun lead to events such as solar eclipses and lunar eclipses.
Human Activities: Earth is people’s home and habitat. Throughout history, humans have explored the Earth, used natural resources, created settlements, and changed their environment. Industry, agriculture, technology and other human activities have had significant impacts on the Earth.
Earth is of great importance as it is the only planet in the known universe where life exists. People need to manage natural resources sustainably, protect the environment and find solutions to global problems such as climate change. Understanding the value and importance of the Earth helps us achieve the goal of leaving a sustainable world for future generations.
Mars:
Size and Position: Mars is an inner planet, similar to Earth. It is approximately 6,779 kilometers in diameter, about half the size of Earth. Mars is at an average distance from the Sun about 227.9 million kilometers.
Surface Features: The surface of Mars is quite diverse. There are different geographical features such as grand canyons, mountains, volcanoes, plains and deserts. The largest canyon, Valles Marineris, is much wider than the Grand Canyon on Earth. Mars is also home to a huge volcano called Olympus Mons, the highest mountain in the Solar System.
Atmosphere: Mars’ atmosphere is rather sparse and thin compared to Earth’s atmosphere. Carbon dioxide (CO2) makes up most of the atmosphere. Small amounts of nitrogen and argon are also present. The Martian atmosphere reduces harmful radiation from the Sun, preventing it from reaching the planet’s surface, but because it is much thinner compared to Earth’s atmosphere, its thermal effects are limited.
Water Traces: There is evidence of water in Mars’ past. Research shows that there are ancient river beds, lakes, glaciers and ice remnants on the Martian surface. Also on Mars are polar ice caps that change seasonally. Water is an essential ingredient for the existence of life, and traces of water on Mars are one of the key elements in the search for life on the planet.
Explorations and Explorations: Mars is a major focus of interest in space exploration. Many space missions have been sent to Mars and have collected important data about the planet. NASA’s Mars exploration program includes missions to study the Martian surface and atmosphere, search for potential traces of life, and evaluate the potential for humans to travel to Mars in the future.
Manned Missions: The idea of manned voyages and colonization to Mars is gaining more and more attention. Space agencies and private companies are working on plans to send humans to Mars. Such missions aim to further investigate Mars’ atmosphere, water resources and potential traces of life, and test humanity’s ability to live in space.
Venus:
Venus is one of the second-ranked inner planets in the Solar System. Here are some key features about the planet Venus:
Size and Position: Venus has a fairly similar size to Earth. It is approximately 12,104 kilometers in diameter, which is only slightly smaller than Earth. Venus is at an average distance from the Sun about 108 million kilometers.
Atmosphere: The atmosphere of Venus consists of a very dense and thick layer. Most of it is carbon dioxide (CO2). It also contains small amounts of nitrogen and other gases. Venus’ atmosphere creates a dense greenhouse effect, keeping the planet’s temperature much higher than Earth’s.
Temperature: Venus is the hottest planet in the Solar System. Greenhouse gases in the atmosphere prevent the sun’s rays from reaching Venus and cause the temperature to rise. Surface temperatures have been measured around 470°C (878°F), making Venus the hottest planet.
Surface Features: The surface of Venus is mostly covered with volcanic plains, mountains and craters. Venus, which has an intense volcanic activity, has thousands of volcanic mountains. It also includes a large continental mass called Aphrodite Terra and the highest mountain called Maxwell Montes.
Atmospheric Conditions: There are high winds and dense cloud layers in the Venus atmosphere. Clouds are made up of sulfuric acid and other acid compounds. These dense clouds make it difficult to observe the planet’s surface and make it difficult to learn more about the surface.
Solar Energy and Winds: The atmosphere of Venus absorbs energy from sunlight, causing winds to form. Venus is characterized by super-fast winds with rapid rotational movement in the equatorial region, unlike winds on Earth.
Planetary Rotation: Venus revolves around the Sun more slowly than Earth.
Mercury:
Mercury is the closest to the Sun and one of the smallest planets in the Solar System. Here are some key features about the planet Mercury:
Size and Position: Mercury is the smallest planet in the Solar System. It is approximately 4,879 kilometers in diameter, which is only about a quarter of the Earth’s. Mercury is at an average distance from the Sun about 58 million kilometers.
Surface Features: Mercury’s surface is mostly made up of craters, mountains, and plains. Craters represent pit-like structures formed as a result of impacts. The largest crater on Mercury is the Caloris Basin and is the largest impact basin in the Solar System.
Proximity to the Sun: Mercury is quite hot due to its proximity to the Sun. Surface temperatures range around 430°C (800°F). At the same time, Mercury has a formidable gravitational pull due to the gravitational pull of the Sun.
Atmosphere: Mercury has a rather sparse and thin atmosphere. Its atmosphere contains mostly helium and traces of hydrogen. However, since its atmosphere is very weak, it constantly interacts with the solar wind and other external influences.
Lengths of Night and Day: Due to Mercury’s proximity to the Sun, the lengths of day and night are quite different. One Mercury day is equivalent to a period on Earth lasting approximately 176 days. That is, while one side faces the Sun, the other side remains in complete darkness.
Absence of Satellites: Mercury is a planet without a natural satellite. This means that due to Mercury’s proximity to the Sun, its gravitational force is not sufficient. As with other planets, Mercury does not have a satellite image in the night sky because it has no moon.
We will continue to talk about space in our next articles…
