The Earth

Photos of Earth, taken by NASA

The Earth is the third planet of the Sun which is the largest and fifth largest planet of the eight planets in the Solar System. Earth is also the largest planet of the four planets of the Earth Solar System. Earth is sometimes called the world or the Blue Planet.Earth formed about 4.54 billion years ago, and life appeared on its surface in the first billion years. The Earth's biosphere then slowly alters the atmosphere and other basic physical conditions, allowing the breeding of organisms and the formation of the ozone layer, which along with the Earth's magnetic field blocks harmful solar radiation and allows microscopic living creatures to breed safely on land. Physical properties, geological history, and Earth's orbit allow life to survive.The Earth's lithosphere is divided into rigid segments, or tectonic plates, which have been moving throughout the Earth's surface for millions of years. More than 70% of the Earth's surface is covered by water, and the remainder consists of continents and islands that have many lakes and other water sources that contribute to the formation of the hydrosphere. Most of the Earth's poles are covered in ice; solid ice in Antarctic ice sheet and sea ice in polar ice packs. The interior of the Earth remains active, with an inner core composed of solid iron, while the outer core is a fluid that creates a magnetic field, and a relatively thick layer of thickness in the mantle section.The Earth interacts gravitatively with other objects in outer space, especially the Sun and the Moon. When it encircles the Sun in one orbit, the Earth rotates on its axis of 366,26 times, which creates 365.26 solar days or a ciderine year. [Note 7] The Earth's rotation on its axis is tilted 23.4 ° from the orbital plane, seasons on Earth's surface with a tropical one-year period (365.24 solar days). The moon is Earth's only natural satellite, which began to orbit Earth about 4.53 billion years ago. The gravitational interaction between the Moon and the Earth stimulates the tide of the sea, stabilizes the axis of the axis, and gradually slows down the Earth's rotation.Earth is home to millions of living things, including humans. Earth's mineral resources and other biosphere products contribute to the provision of resources to support the global human population. The human-inhabited Earth region is grouped into 200 sovereign states, which interact with each other through diplomacy, travel, trade, and military action.

The slope of the Earth's axis (or obliquitas) and its relation to the rotation axis and the orbital plane

The relative time of the Earth's rotation relative to the Sun - called the day of the Sun - is 86,400 seconds from the average Sun time (86.400,0025 SI sec). Since the current day period of the Sun of the Earth is longer than the period when the 19th century was due to tidal acceleration, every day varies from 0 to 2 SI ms longer.

When the Earth's rotation relative to a fixed star, called the day of stars by the International Earth Rotation and Reference Systems Service (IERS), is 86.164.098903691 seconds from the time of the average Sun (UT1), or 23h 56m 4,098903691s. The time of Earth's rotation relative to the precession or movement of the vernal equinox, called sideris day, is 86.164,09053083288 seconds from the time of the average Sun (UT1) (23h 56m 4.09053083288s) to 1982. Thus, the sideris day is approximately shorter 8 , 4 ms from star day. The average solar day length in seconds SI is calculated by IERS for the period 1623-2005 and 1962-2005.

In addition to meteors in the atmosphere and low-orbiting satellites, the main movement of celestial bodies on Earth is to the west, at a rate of 15 ° / hr = 15 '/ min. For celestial bodies near the equatorial space, its movement is seen in the diameter of the Sun and the Moon every two minutes; from the surface of the Earth, the size of the Sun and the Moon are more or less the same.

Animations featuring the Earth's rotation.

The Earth orbits the Sun at an average distance of about 150 million kilometers per 365.2564 average solar day, or one year of cideris. From Earth, it will be clearly seen the movement of the Sun to the east at a rate of about 1 ° / day, which clarifies the diameter of the Moon or Earth every 12 hours. Because of this movement, the Earth takes an average of 24 hours (or day of the sun) to complete the full rotation on its axis so that the Sun can return to the meridians. The average Earth orbital velocity is 29.8 km / s (107,000 km / h), fast enough to travel the same distance as the planet's diameter, or about 12,742 km in seven minutes, and the distance to the Moon, 384,000 km within 3 , 5 hours.The moon spins with Earth around the line of electricity every 27.32 days. When combined with the Earth-Moon revolution system around the Sun, the synodic Moon period from the new moon to the new moon is 29.53 days. When viewed from the north pole of the sky, the Earth moves, the Moon, and their axis rotations counterclockwise. Whereas if viewed from the viewpoint above the north pole, both the Sun and Earth, the Earth rotates in the opposite direction around the Sun. Earth's orbits and axes are irregular; Earth's axis is tilted approximately 23.4 degrees from the Earth-Sun orbit (ecliptic) orbit, and the Earth-Moon orbiting orbit plane is approximately ± 5.1 degrees from the Earth-Sun orbit plane. Without this slope, the eclipse will appear every two weeks, alternating between a lunar eclipse and a solar eclipse.Sfer hill, or the gravitational sphere of Earth's influence, is about 1.5 Gm or 1,500,000 km in radius. This is the maximum distance when the Earth's gravitational influence is stronger than the Sun and the distant planets. Objects must orbit the Earth within this radius, or they will be affected by the perturbation of the Sun's gravity.The Earth, together with the Solar System, lies in the Milky Way galaxy and orbits about 28,000 light-years from the center of the galaxy. Currently, the Earth is about 20 light-years above the galactic plane of Orion's spiral arms. or more completely can be directly linked https://id.wikipedia.org/wiki/Bumi

THE PLANET VENUS

VENUS is the second closest planet from the Sun after Mercury. The planet orbits the Sun for 224.7 Earth days. Venus has no natural satellite and is named after the goddess of love and beauty in Roman mythology. After the Moon, the planet is the brightest natural object in the night sky, with a visible magnitude of -4.6 which is bright enough to produce a shadow. Venus is an inferior planet with an elongation angle of 47.8 °. The maximum brightness of the planet can be seen immediately before sunrise or after sunset, so it is called the Morning Star or the Twilight Star.Venus is a terrestrial planet and is sometimes called the Earth's "planet Earth" because of its size, gravity, and similar compositions (Venus is the closest planet from Earth and the closest planet to Earth). However, in another case the planet is very different from Earth. The planet has the densest atmosphere among four Earth planets comprising 96% carbon dioxide. Venus's surface atmospheric pressure is 92 times larger than Earth's. With an average surface temperature of 735 K (462 ° C; 863 ° F), Venus is the hottest planet in the Solar System. The planet does not have a carbon cycle that traps carbon in rocks and surface appearance, nor does it have organic life that can absorb carbon in the form of biomass. Venus is enveloped by an opaque layer of highly reflective sulfuric acid clouds, so the surface can not be seen from outer space. Venus may have once had an ocean, but the ocean evaporated due to an increase in temperature caused by the effects of a greenhouse. Much of the water may have been biodegradable, and the solar wind has made free hydrogen undergoing outer space as a result of the absence of an internal magnetic field on Venus. The surface of Venus itself is descending, dry, and interspersed by rocks that are periodically updated by volcanic activity. 

satellite venera crosses planet venus

 Much of Venus's surface appears to be formed through volcanic activity. The number of volcanoes on Venus is more than Earth, with 167 large volcanoes that can reach up to 100 km wide. The only volcanic compound on Earth of this size is the Great Island of Hawaii. However, it does not mean that Venus is volcanically more active than Earth; it is due to the older Venus crust. By comparison, the surface of Venus is estimated to be 300-600 million years old, while on Earth, oceanic crust is continuously recycled through a subduction process at the boundary between tectonic plates, resulting in an average age of about 100 million years. ] Some evidence suggests the ongoing volcanic activity on Venus. During the Venera program launched by the Soviet Union, Venera 11 and Venera 12 rides found lightning, and Venera 12 recorded the thunder while landing. Venus Express launched by the European Space Agency also found lightning in the atmosphere. Although lightning on Earth is caused by rain, there is no rain on the planet Venus (although sulfuric acid drops from the atmosphere, and then evaporates at an altitude of 25 km above the surface). The possibility of lightning produced by ash from volcanic eruptions. Other evidence comes from measuring the levels of sulfur dioxide in the atmosphere, which is tenfold between 1978 and 1986. This suggests that initial sulfur dioxide levels are driven by large volcanic eruptions. Almost a thousand impact craters are spread evenly on the surface of Venus. In other cranial celestial bodies, such as Earth and the Moon, the craters appear to be degraded. On the Moon, degradation is caused by subsequent collisions, while on Earth the process is driven by wind and rain erosion. On Venus, 85% of craters are still in a state that has not been degraded. The number of craters and their un-degraded state indicates that the planet experienced a globally resurfacing event some 300-600 million years ago, which was then followed by reduced volcanism. While the Earth's crust is continuously moving, Venus's crust is suspected of not being able to support the process. Without the existence of tectonic tectonics that can reduce the temperature of the mantle, Venus undergoes a cyclical process that causes a rise in mantle temperature to ultimately weaken the crust. Then, for about 100 million years, large-scale subduction recycled the Venusian crust.

The diameters of the craters on Venus vary from 3 km to 280 km. There is no crater whose diameter is less than 3 km due to the influence of the dense atmosphere on the foreign object entering Venus. An object with a kinetic energy smaller than a certain number will be slowed down by the atmosphere so as not to produce a collision crater. An object with a diameter smaller than 50 meters will break and burn in the atmosphere before it reaches the surface.

Venus has a very dense atmosphere, which consists of 96.5% carbon dioxide and 3.5% nitrogen. Its atmospheric mass is 93 times larger than Earth's atmosphere, while the pressure on the surface of the Venus planet is 92 times larger than on Earth's surface-the pressure is roughly equivalent to the ocean as deep as 1 kilometer on Earth. Venus density on the surface of Venus was recorded at 65 kg / m³ or 6.5% of the water density. The atmosphere is rich in CO2 and the thick sulfur dioxide cloud produces the strongest greenhouse effect in the Solar System, so that the average surface temperature of Venus is 462 ° C (864 ° F). [11] [40] As a result, the surface of Venus is hotter than Mercury, which has a minimum surface temperature of -220 ° C (-364.0 ° F) and a maximum surface temperature of 420 ° C (788 ° F), though Venus is located farther from the Sun and as a result only acquire 25% of irradiance received by Mercury. The surface of Venus is often described as hell. The temperature at Venus is also higher than the temperature for sterilization.Research shows that billions of years ago, the atmosphere of Venus is more similar to the Earth's atmosphere than the present Venus atmosphere, and there may be water on the surface. However, after a period of 600 million to several billion years, a sustainable greenhouse effect is caused by the evaporation of water that produces greenhouse gases in the atmosphere. Although the surface of Venus can not support life as on Earth, the possibility of existence of a habitable niche in the lower and middle bottom layers can not be ignored.Thermal inertia and heat transfer by the wind in the lower atmosphere indicate that the surface temperature of Venus is not much different between the light and dark side, although the planet's rotation is very slow. The wind on the surface is slow with speeds of several kilometers per hour. However, due to the high atmospheric density on Venus's surface, the wind is significant and capable of removing dust and small rocks on the surface. In addition, the wind can also complicate pedestrians even when heat, pressure, and lack of oxygen are not a problem.

Above the CO2 layer there is a thick cloud composed of sulfur dioxide and sulfuric acid. The beginning reflects and scatters about 90% of sunlight, thus inhibiting the observation of Venus's surface. Due to this permanent starting layer, although the distance of Venus closer to the Sun than the Earth, the surface of Venus is not as bright as Earth. Winds as fast as 300 km / h (190 mph) above the clouds around Venus every four to five Earth days. Venus wind speed is 60 times faster than the rotation of Venus, while the fastest wind speed on Earth is only 10-20% of Earth's rotational speed.The surface of Venus is isothermal; the planet has a constant temperature not only between day and night, but also between the equator and the poles. The slope of the venous axis of less than 3 ° also minimizes seasonal temperature variations. The only considerable temperature variation depends on the altitude. In 1995, the Magellan vehicle successfully captured the image of a highly reflective substance at the top of the highest mountain that closely resembles the snow on Earth. This substance is likely to form from the same process with snow, albeit at much higher temperatures. The snow is too volatile on the surface, so as to rise to a cooler height in the form of gas, and then undergo precipitation. The identity of this substance is still not known for certain, but there are various speculations such as tellurium and lead sulphide (galena).

The Venusian cloud is capable of producing lightning like a cloud on Earth. The existence of lightning has been a controversy since its first discovery by the Venera rides. In 2006-07, Venus Express managed to find electromagnetic wave electrons, which are signs of lightning. Its intermittent appearance shows patterns related to weather activity. In 2007, Venus Express found the atmospheric vortex at the south pole of Venus. In addition, in 2011, this vehicle also managed to find the ozone layer in the upper atmosphere of Venus

PLANETS MERKURIUS

Mercury/Merkurius is the smallest planet in the solar system and also closest to the Sun with a revolution of 88 days and 59 days of rotation. The brightness of the planet ranges from -2 to 5.5 in apparent magnitude but is not easily visible because of its viewing angle with the small Sun (with the most distant range of 28.3 degrees) Mercury can only be seen at dawn or maghrib. is known about Mercury because only one spacecraft ever approached Mariner 10 in 1974 to 1975. Mariner 10 only managed to map about 40 to 45 percent of the planet's surface.

Similar to the Moon, Mercury has many craters and also does not have natural satellites as well as atmosphere. Mercury has an iron core that creates a magnetic field with a strength of 0.1% of the Earth's magnetic field strength. The surface temperature of Mercury ranges from 90 to 700 Kelvin (-180 to 430 degrees Celsius).

The earliest recorded observations of Mercury date from the Sumerians in the third millennium BC. The Romans named the planet by the name of one of their gods, Mercury (also known as Hermes in Greek mythology and Nabu in Babylonian mythology). The astronomical symbol for mercury is an abstraction from Mercury's head of the god with a winged hat on caduceus. The Greeks of Hesiod named the Mercury of Stilbon and Hermaon because before the fifth century BC they thought that Mercury were two different celestial bodies, one only visible at sunrise and the other only visible at sunset. In India, Mercury is named Buddha (बुध), the son of the moon Candra. In Chinese culture, Korea, Japan and Vietnam, Mercury is called the "water star". The Hebrews call it Kokhav Hamah (כוכב חמה), "the star of the hot one" ("the hot one" means the Sun). Mercury's diameter is 40% smaller than Earth (4879.4 km), and 40% larger than the Moon. Its size is also smaller (though more dense) than the satellites of Jupiter, Ganymede and Saturn's satellites, Titan.

 An animated photo of the distance between Mercury and the Sun

With a diameter of 4879 km on the equator, Mercury is the smallest planet of the four Earth planets in the Solar System. The distance of mercury to the sun is 57 million km, and the distance of Mercury with Earth is 92 million km. Mercury comprises 70% metal and 30% silicates and has a density of 5.43 g / cm3 just below the Earth's density. But if the effect of gravity pressure is not calculated then Mercury is denser than Earth with an uncompressed density of Mercury of 5.3 g / cm 3 and Earth is only 4.4 g / cm3.

Mercury density is used to estimate its inner structure. The high density of the Earth is created by the pressure of gravity, especially in the core. Mercury, however, is much smaller and its interior does not exist like the earth, so its high density is suspected because the planet has a large nucleus and is rich in iron. Earth scientists estimate that Mercury's core occupies 42% of its volume (Earth's core occupies only 17% of Earth's volume). According to recent research, most likely the core of Mercury is liquid.

The 600 km coat envelopes Mercury's core and Mercury's crust allegedly as thick as 100 to 200 km. Mercury's surface has many meager hills, some hundreds of kilometers in length. It is suspected that these hills are formed because Mercury's core and mantle cools and shrinks when the crust is petrified.

Mercury contains more iron than any other planet in the solar system and several theories have been proposed to explain it. The most widely accepted theory is that Mercury initially had a metal-to-silicate ratio similar to the common Kondrit meteor and had a mass of about 2.25 times its current mass. But at the beginning of the solar system's history, Mercury was hit by a planetesimal about one-sixth of its mass. The clash has removed most of Mercury's original crust and mantle and left its core. The same process has also been proposed to explain the creation of the Moon.

Another theory suggests that Mercury may have been formed from the Sun's nebula before the Sun's output energy has stabilized. Mercury originally had twice its current mass, but with the sun's protrusion, the temperature around Mercury could reach about 2500 to 3500 Kelvin and probably reach 10,000 Kelvin. Most of Mercury's surface will evaporate at such temperatures, creating an atmosphere of "steam rock" that may be blown by the solar wind.

 Aphelioncharacterizing the orbits of Mercury's planet : 69.816.900 km0.466 697 SAPerihelion 46,001,200 km0.307 499 SASemi-major axis 57,909,100 km0.387 098 SAEccentricity 0.205 630  The orbital period is 87,969 1 day(0.240 846 years)Synodic period 115,88 d Average orbital speed of 47.87 km / s. Anomalies averaged 174,796 °Inclination 7,005 ° to ecliptic3.38 ° to the equator of the Sun.6.34 ° to the invariable field. The longitude of the node is 48,331 °The perihelion argument is 29.124 °No Satellite

The physical feature of the planet Mercury is The radius averages 2,439.7 ± 1.0 km. 0.3829 EarthThe precision <0.0006 [6]Surface area 7,48 × 107 km²0.108 Earth. Volume 6,083 × 1010 km³0.054 Earth [5]Masses 3,3022 × 1023 kg0.055 Earth. Average mass of 5.427 g / cm³ Surface gravity at the equator is 3.7 m / s²0.38 g 4.25 km / s off speed. Sideris Day 58,646 day1407.5 hours Rotation speed 10,892 km / hThe axial tilt of 2.11 '± 0.1' Asensio rekta for the North Pole 18 j 44 men 2 d281,01 ° Declination for the North Pole 61.45 ° Albedo 0.119 (bound)0.106 (geometric) Surface temperature 0 ° N, 0 ° W 85 ° N, 0 ° Wmin average max100 K 340 K 700 K80 K 200 K 380 KMagnitude looks up to -1.9 Diameter angle 4.5 "- 13"

THE SUN

 The Sun

The Sun is the host star of the Solar System and is a major component of this Solar System. This star is 332,830 earth masses. This large mass causes a large enough nuclear density to support the continuity of nuclear fusion and spewing out enormous amounts of energy. Most of this energy is emitted into space in the form of eletromagnetic radiation, including the optical spectrum.

The sun is categorized into a medium-sized yellow dwarf star (type G V), but this name can cause misunderstanding, as compared to the stars inside the Milky Way, the Sun is large and brilliant. Stars are classified by the Hertzsprung-Russell diagram, a graph illustrating the relationship of a star's luminosity to its surface temperature. In general, the hotter stars will be more brilliant. The stars following this pattern are said to lie in the main sequence, and the Sun lies right in the middle of this series. However, the more brilliant and hotter stars of the Sun are scarce, while the fainter and cooler stars are common.

It is believed that the position of the Sun in the main sequence is generally the "peak life" of a star, due to the inexhaustible hydrogen stored for nuclear fusion. Today the sun is growing more and more brilliant. At the beginning of his life, his level of brightness is about 70 percent of his current tone.

The sun is metallicity categorized as the star of "population I". The star of this category is formed more recently at the rate of evolution of the universe, thus containing more heavier elements than hydrogen and helium ("metal" in astronomical designations) compared to the "population II" star. Elements heavier than hydrogen and helium formed in the core of the ancient star which then exploded. The first generation stars need to become extinct before the universe can be filled with these heavier elements.

The oldest stars contain very little metal, while new stars have a higher metal content. This high level of meteorization is thought to have an important influence on the formation of the Solar System, because the formation of planets is the result of metal clumping

When the total solar eclipse, the Sun's corona can be seen with the naked eye during a brief period of totality.

Chemically, approximately three-quarters of the Sun's mass consists of hydrogen, while the remainder is predominantly helium. The remainder of the mass (1.69%, equivalent to 5,629 times the mass of the Earth) consists of heavy elements such as oxygen, carbon, neon, iron, and others.The sun formed about 4.6 billion years ago due to the gravitational decay of an area within a large molecular cloud. Most of the material is gathered in the middle, while the rest of it crops up into circulating disks that will become the Solar System. The central mass is getting hotter and denser and ultimately starts thermonuclear fusion at its core. It is alleged that almost all other stars are formed by a similar process. Classification of the Sun's stars, by their spectral class, is the main sequence star G (G2V) and is often classified as a yellow dwarf because radiation appears to be more intense in the yellow-red portion of the spectrum. Although the color is white, from the surface of the Earth the Sun appears yellow due to the mixing of blue light in the atmosphere. According to the spectral class label, G2 denotes a surface temperature of about 5778 K (5505 ° C) and V indicates that the Sun, like other stars, is the main sequence star, so its energy is created by the nuclear fusion of the hydrogen nucleus into helium. In essence, the Sun fuses 620 million metric tons of hydrogen every second.In the past, the Sun was viewed by astronomers as small and insignificant stars. Now, the Sun is considered brighter than about 85% of stars in the Milky Way dominated by red dwarfs. The absolute magnitude of the Sun is +4,83. However, as the closest star to the Earth, the Sun is the sunniest thing in the sky with an apparent magnitude of -26.74. The hot corona of the Sun continues to expand in outer space and create the solar wind, the flow of charged particles moving up to a heliopause of about 100 AU. The bubbles in the interstellar medium formed by the solar wind, the heliosphere, are the largest concatenated structures in the Solar System.The sun is currently moving through the Local Antarcross Cloud (near Cloud G) in the Local Bubble zone, precisely within the inner circle of the Orion Arms in the Milky Way galaxy. Of the nearest 50 star systems within 17 light years from Earth (the nearest star is a red dwarf named Proxima Centauri about 4.2 light-years away), the Sun has the fourth largest mass. The Sun orbits the center of the Milky Way at a distance of approximately 24,000-26,000 light years from the center of the galaxy. When viewed from the north pole of the galaxy, the Sun completes one orbit clockwise in the period of about 225-250 million years. Because the Milky Way is moving relative to the cosmic microwave background radiation (CMB) toward the Hydra constellation at a speed of 550 km / s, the Sun's velocity relative to CMB is about 370 km / sec towards the Crater or Leo.The average distance of the Sun from the Earth is about 149.6 million kilometers (1 AU), although the distance varies as the Earth moves away from perihelion in January to aphelion in July. At this average distance, light moves from the Sun to Earth for 8 minutes 19 seconds. This solar energy helps the development of virtually every life form on Earth through photosynthesis and alters Earth's climate and weather. The extraordinary impact of the Sun on Earth has been observed since prehistoric times. The sun is also considered by some civilizations as gods. An accurate scientific understanding of the Sun grew slowly. In the 19th century, some well-known scientists began to know little about the physical composition and sources of solar energy. This understanding is still developing today. There are a number of Sun behavioral anomalies that have not been scientifically explained.

Solar System Milky Way Galaxy

        The Solar System [a] is a collection of celestial bodies consisting of a star called the Sun and all objects bound by its gravitational force. These objects include eight known planets with elliptical orbits, five dwarf planets, 173 identified natural satellites [b], and millions of other celestial bodies (meteors, asteroids, comets).The Solar System is divided into the Sun, the four inner planets, the asteroid belt, the four outer planets, and in the outermost are Kuiper belts and discs scattered. The Oort cloud is thought to lie in the furthest area about a thousand times beyond the outermost.Based on the distance from the Sun, the eight planets of the Solar System are Mercury (57.9 million km), Venus (108 million km), Earth (150 million km), Mars (228 million km), Jupiter (779 million km), Saturn (1,430 million km), Uranus (2,880 million km), and Neptune (4,500 million km). Since mid-2008, there are five aerial objects that are classified as dwarf planets. The orbit of the dwarf planets, except Ceres, is farther away from Neptune. The five dwarf planets are Ceres (415 million km in the asteroid belt, formerly classified as the fifth planet), Pluto (5.906 million km, formerly classified as the ninth planet), Haumea (6,450 million km), Makemake (6,850 million km) and Eris (10.100 million km).

Six of the eight planets and three of the five dwarf planets are surrounded by natural satellites. Each of the outer planets is surrounded by a planetary ring consisting of dust and other particles.