The Earth is a relatively small celestial object. It is the third planet orbiting an average star, our Sun, located in the Orion arm, sometimes called the Orion Spur; it is a minor arm located in between the Sagittarius Arm and the Perseus arm of the Milky Way, a barred spiral galaxy. Our solar system orbits the central bulge of our galaxy at a radius of 1.7 billion AU and our period of galactic revolution is 230 million years at a tangential velocity of 828,000 km/hr relative to the center. Our solar system has one main sequence star, 4 inner rocky planets, the asteroid belt, 4 outer large gaseous planets, the Kuiper Belt of small icy objects, and the outermost Oort Cloud of icy objects made of water, ammonia, and methane. It extends from about 2000-5000 AU to an outer distance of as much as 100,000 AU.
The Earth completes one rotation every 23 hrs 56 min. and completes 365.25 rotations (days) during one revolution around the Sun, or 1 Earth Year. The Earth’s average orbital velocity is 29.8 km/s and its rotational velocity is about 460 m/s. The average radius of Earth’s solar orbit is 149,587,817 km, or about 1 AU. About 1320 Earths would fill Jupiter’s volume and around 1,300,000 would fill the Sun’s. It has a density of 5.5 g/cm3, similar to the other rocky inner planets that are composed of heavy elements, but much greater that the outer planets that are mostly hydrogen and helium. Its mass is 5.97×1024 kg. It has a slightly greater equatorial circumference then polar, this is due to Earth’s rotation on its axis and the Sun’s gravitational pull during the Earth’s early molten stage.
Over 4.6 billion years ago, a large molecular cloud located within one branch of the Milky Way galaxy had been the site of the formation ...
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...nd the debris orbiting Earth also accreted into the Moon. As the number of planetesimal collisions diminished, the Earth began to cool. A solid crust had formed by about 3.8 billion years ago. The crust thickened to form one large landmass called Pangea. Then, the crustal plates began to move due to the convective mantle. As they pulled apart, a new, thin ocean floor formed. The Earth’s atmosphere formed by outgassing, or the release of gas trapped within the interior of the planet by volcanic activity. The Earth’s oceans were formed when water vapor in the atmosphere condensed and fell as rain to form the oceans. Light elements like He and H escaped to space, leaving behind an early atmosphere of volcanic compounds like NH3, CH4, N and S compounds, water, and carbon dioxide. As of about 3.5 billion years ago, the Earth’s surface was set for the origin of life.
To better understand the planets, we need to first have a basic understanding of our
The Orion Nebula is one of the closest stellar regions to the Earth. Using parallax measurements, it has been estimated that this nebula is only 1,500 light years away. In addition, the Orion Nebula is a relatively young star cluster, with an approximate age of less than one million years. It has even been speculated that some of the younger stars within the cluster are only 300,000 years old.
Solar nebula is a rotating flattened disk of gas and dust in which the outer part of the disk became planets while the center bulge part became the sun. Its inner part is hot, which is heated by a young sun and due to the impact of the gas falling on the disk during its collapse. However, the outer part is cold and far below the freezing point of water. In the solar nebula, the process of condensation occurs after enough cooling of solar nebula and results in the formation into a disk. Condensation is a process of cooling the gas and its molecules stick together to form liquid or solid particles. Therefore, condensation is the change from gas to liquid. In this process, the gas must cool below a critical temperature. Accretion is the process in which the tiny condensed particles from the nebula begin to stick together to form bigger pieces. Solar nebular theory explains the formation of the solar system. In the solar nebula, tiny grains stuck together and created bigger grains that grew into clumps, possibly held together by electrical forces similar to those that make lint stick to your clothes. Subsequent collisions, if not too violent, allowed these smaller particles to grow into objects ranging in size from millimeters to kilometers. These larger objects are called planetesimals. As planetesimals moved within the disk and collide with one another, planets formed. Because astronomers have no direct way to observe how the Solar System formed, they rely heavily on computer simulations to study that remote time. Computer simulations try to solve Newton’s laws of motion for the complex mix of dust and gas that we believe made up the solar nebula. Merging of the planetesimals increased their mass and thus their gravitational attraction. That, in turn, helped them grow even more massive by drawing planetesimals into clumps or rings around the sun. The process of planets building undergoes consumption of most of the planetesimals. Some survived planetesimals form small moons, asteroids, and comets. The leftover Rocky planetesimals that remained between Jupiter and Mars were stirred by Jupiter’s gravitational force. Therefore, these Rocky planetesimals are unable to assemble into a planet. These planetesimals are known as asteroids. Formation of solar system is explained by solar nebular theory. A rotating flat disk with center bulge is the solar nebula. The outer part of the disk becomes planets and the center bulge becomes the sun.
Waller, William H. The Milky Way: An Insider's Guide. Princeton, N.J: Princeton UP, 2013. 42+. Print.
The gas giants are a collection of planets in our solar system. As can be told from their name, they are mostly composed of differing mixtures of gases and ices. The gas and ice composition in question varies among the different planets. This mix of gases gives much of the planets an extremely thick atmosphere. At the very center of a gas giant is a core of liquid heavy metals. The gas giants are also called Jovian planets, taken from the largest planet in our solar system: Jupiter. Due to the fact the the majority of a gas giant planet is gas, the planet isn’t very dense and therefore, very large as a result. In fact, all of the gas giants are vastly larger than all of the terrestrial planets. Another common factor of the gas giants are their large amount of moons. The terrestrial planet, Mars, has the largest amount of moons, 2. The amount of moons of Mars is dwarfed in comparison to Saturn’s and Jupiter’s moo...
2,870,990,000 km (19.218 AU) from the Sun, Uranus hangs on the wall of space as a mysterious blue green planet. With a mass of 8.683e25 kg and a diameter of 51,118 km at the equator, Uranus is the third largest planet in our solar system. It has been described as a planet that was slugged a few billion years ago by a large onrushing object, knocked down (never to get up), and now proceeds to roll around an 84-year orbit on its belly. As the strangest of the Jovian planets, the description is accurate. Uranus has a 17 hour and 14 minute day and takes 84 years to make its way about the sun with an axis tilted at around 90° with retrograde rotation. Stranger still is the fact that Uranus' axis is almost parallel to the ecliptic, hence the expression "on its belly".
Our sun is the central pivot point to which or entire planet and solar system is built around. With out it all life on our planet would cease to exist. Within this paper we will explore how our Sun and solar system formed and came to resemble what we see today.
Other changes are more gradual but much more dramatic when viewed over long time scales. Powerful telescopes reveal new stars coalescing from galactic dust, just as our sun did more than 4.5 billion years ago. The earth itself formed shortly thereafter, when rock, dust, and gas circling the sun condensed into the planets of our solar system. Fossils of primitive microorganisms show that life had emerged on earth by about 3.8 billion years ago.
To properly understand where all elements on Earth came from, it is essential to first learn about human understanding of how the universe started. One of the widely accepted theories is “the Big Bang theory”. The Big Bang theory is a method to explain what the universe was like at the very beginning. Most scientists working in the field of astronomy believe that the universe did have a beginning and its age is finite. One claim that supports this view is that if the universe was infinitely old, there should be stars in every direction possible, either a star or the remains of a star. According to the current understanding, there existed nothing before the Big Bang, but during and after the Big Bang, everything we can imagine sprang into
A galaxy, also called a nebula, consists of billions of stars, interstellar gas, dust, and dark matter which are all bound to form a massive cloud in which we live in. Although it cannot be very well explained, dark matter makes up at least 90% of a galaxy’s mass. Galaxies also contain billions upon billions of stars and their diameter can range from 1,500 to 300,000 light years. That’s huge! The Milky Way, the galaxy in which we live in, is one of about 170 billion galaxies in the observable universe. Our Sun is one of the billions of stars in our galaxy, and our eight planets revolve around this star in only a tiny part of our galaxy. “The Earth’s solar system is believed to exist very close to the Galaxy’s galactic plane, due to the fact that the Milky Way essentially divides the night sky into two virtually equal hemispheres” ("All About the Milky"). It definitely makes people second guess the fact of there being life on other planets.
Our solar system has eight planets, their moons and satellites, and they are all orbiting the Sun. The eight planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Pluto used to be the ninth planet but IAU changed the definition of planet and Pluto did not meet the standards so it is now a Dwarf planet.
¬¬¬¬¬¬¬¬¬¬¬¬The Earth is a large and mysterious planet that we are just beginning to understand. There are many cycles and forces that go hand in hand in creating different environments on Earth. In this essay we will go over the five major cycles, the Atmosphere, Sun, Water/Ocean, Wind, and Earth cycles. We will also go over how the cycles interact and work together to form one of the most bio diverse planets in our galaxy.
Earth is made up of approximately 71% of water. A majority of this water is from the oceans. It is estimated that one fifth of the planet includes oxygen made by plants. The Earth floats around on its axis in 23.434 hours, that being said it takes the earth 365.26 days to circle the sun. Air is around the Earth it thins out the farther it is from the surface.
Earth system refers to the earths interacting physical, biological, and chemical processes. The system consists of land, oceans, atmosphere and poles. The earth system has four spheres, including the geosphere, the hydrosphere, the atmosphere, and the biosphere. The geosphere refers to the solid parts of the earth system, including earth’s rocky crust, mantle, and the metallic core. Within the geosphere is the lithosphere, which only refers to the uppermost layers of solid earth. The uppermost layers of solid earth are the oceanic and continental crust rocks. Just below the crust is the mantle, which is composed mostly of magnesium and iron silicate minerals. The mantle accounts for about 2/3 of the
The idea behind the Solar Nebular Hypothesis is that the solar system was condensed from an enormous cloud of hydrogen, helium, and a few other elements and rocks. Around five billion years this cloud of materials began to spin and contract together into a disk shape under their own gravitational forces. The particles started combined together, protoplanets, to eventually form planets. A great mass of the material eventually began to form together, protosun, and make up the sun.