The Sun is the star that all planets in the Solar System orbit around. It is a medium sized star, sometimes even classed as small compared to the other massive stars out there. Still, it's huge for our Solar System. It is the large celestial body in the Solar System, it is also the hottest, heaviest, most gaseous object with the most bodies orbiting it. It is a nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as visible light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.392 million kilometers (864,000 miles), or 109,34 times that of Earth. Its mass is about 330,000 times that of Earth, and accounts for about 99.864% of the total mass of the Solar System. Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including carbon, oxygen, neon, silicon and iron, that make up nearly 1,3% of the Sun's mass.
The Sun's core fuses more than 600 million tons of hydrogen into helium every single second, converting 4 million tons of matter into energy every second as a result. This energy, which can take between 10,000 and 170,000 years to escape the core, is the source of the Sun's light and heat. When hydrogen fusion in its core has diminished to the point at which the Sun is no longer in hydro-static equilibrium, its core will undergo a marked increase in density and temperature while its outer layers expand, eventually transforming the Sun into a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury and Venus, and render Earth uninhabitable – but not for about five billion years. After this, it will shed its outer layers and become a dense type of cooling star known as a white dwarf, and no longer produce energy by fusion, but still glow and give off heat from its previous nuclear fusion.
The enormous effect of the Sun on Earth has been recognized since prehistoric times. The Sun was thought of by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of solar calendars, one of which is the Gregorian calendar, the predominant calendar in use today. The Sun contains 99.8674 percent of the total mass of the Solar System, and in diameter it is 109.34 times bigger than Earth. If it were the size of a basketball, Earth would be the size of a pin. The Sun can fit more than 1,3 million times our planet Earth inside. Despite all of this, it is just an average sized star, actually sometimes even classified as a bellow average sized star.
- 1 Name and Etymology
- 2 General characteristics
- 3 Sunlight
- 4 Motion and Location
- 5 Composition
- 6 Atmosphere
- 7 Solar Wind
- 8 Formation
- 9 Fate
Name and Etymology
The English word sun developed from Old English sunne. Cognates appear in other Germanic languages, including West Frisian sinne, Dutch zon, Low German Sünn, Standard German Sonne, Bavarian Sunna, Old Norse sunna and Gothic sunnō. All these words stem from Proto-Germanic *sunnōn. This is ultimately related to the word for "sun" in other branches of the Indo-European language family, though in most cases a nominative stem with an l is found, rather than the genitive stem in n, as for example in Latin sōl, Greek ἥλιος hēlios, Welsh haul and Russian солнце solntse (pronounced sontse), as well as (with *l > r) Sanskrit स्वर svár and Persian خور xvar. Indeed, the l-stem survived in Proto-Germanic as well, as *sōwelan, which gave rise to Gothic sauil (alongside sunnō) and Old Norse prosaic sól (alongside poetic sunna), and through it the words for "sun" in the modern Scandinavian languages: Swedish and Danish solen, Icelandic sólin, etc.
In English, the Greek and Latin words occur in poetry as personifications of the Sun, Helios /ˈhiːliəs/ and Sol /ˈsɒl/, while in science fiction "Sol" may be used as a name for the Sun to distinguish it from other stars. The term "sol" with a lower-case 's' is used by planetary astronomers for the duration of a solar day on another planet such as Mars. The principal adjectives for the Sun in English are sunny for sunlight and, in technical contexts, solar /ˈsoʊlər/, from Latin sol – the latter found in terms such as solar day, solar eclipse and Solar System (occasionally Sol system). From the Greek helios comes the rare adjective heliac /ˈhiːliæk/. The English weekday name Sunday stems from Old English Sunnandæg "sun's day", a Germanic interpretation of the Latin phrase diēs sōlis, itself a translation of the Greek ἡμέρα ἡλίου hēmera hēliou "day of the sun".
The Sun is a G-type main-sequence star that comprises about 99.86% of the mass of the Solar System. The Sun has an absolute magnitude of +4.83, estimated to be brighter than about 85% of the stars in the Milky Way, most of which are red dwarfs. The Sun is a Population I, or heavy-element-rich, star. The formation of the Sun may have been triggered by shockwaves from one or more nearby supernovae. This is suggested by a high abundance of heavy elements in the Solar System, such as gold and uranium, relative to the abundances of these elements in so-called Population II, heavy-element-poor, stars. The heavy elements could most plausibly have been produced by endothermic nuclear reactions during a supernova, or by transmutation through neutron absorption within a massive second-generation star.
The Sun is by far the brightest object in the Earth's sky, with an apparent magnitude of −26.74. This is about 13 billion times brighter than the next brightest star, Sirius, which has an apparent magnitude of −1.46. One astronomical unit (about 150,000,000 km; 93,000,000 mi) is defined as the mean distance of the Sun's center to Earth's center, though the distance varies as Earth moves from perihelion in January to aphelion in July. At this average distance, light travels from the Sun's horizon to Earth's horizon in about 8 minutes and 19 seconds, while light from the closest points of the Sun and Earth takes about two seconds less. The energy of this sunlight supports almost all life on Earth by photosynthesis, and drives Earth's climate and weather. The Sun does not have a definite boundary, but its density decreases exponentially with increasing height above the photosphere. For the purpose of measurement, the Sun's radius is considered to be the distance from its center to the edge of the photosphere, the apparent visible surface of the Sun. By this measure, the Sun is a near-perfect sphere with an oblateness estimated at about 9 millionths, which means that its polar diameter differs from its equatorial diameter by only 10 kilometres (6.2 mi). The tidal effect of the planets is weak and does not significantly affect the shape of the Sun. The Sun rotates faster at its equator than at its poles. This differential rotation is caused by convective motion due to heat transport and the Coriolis force due to the Sun's rotation. In a frame of reference defined by the stars, the rotational period is approximately 25.6 days at the equator and 33.5 days at the poles. Viewed from Earth as it orbits the Sun, the apparent rotational period of the Sun at its equator is about 28 days. Viewed from a vantage point above its north pole, the Sun rotates counterclockwise around its axis of spin.
The solar constant is the amount of power that the Sun deposits per unit area that is directly exposed to sunlight. The solar constant is equal to approximately 1,368 W/m2 (watts per square meter) at a distance of one astronomical unit (AU) from the Sun (that is, on or near Earth). Sunlight on the surface of Earth is attenuated by Earth's atmosphere, so that less power arrives at the surface (closer to 1,000 W/m2) in clear conditions when the Sun is near the zenith. Sunlight at the top of Earth's atmosphere is composed (by total energy) of about 50% infrared light, 40% visible light, and 10% ultraviolet light. The atmosphere in particular filters out over 70% of solar ultraviolet, especially at the shorter wavelengths. Solar ultraviolet radiation ionizes Earth's dayside upper atmosphere, creating the electrically conducting ionosphere.
The Sun emits light across the visible spectrum, so its color is white, with a CIE color-space index near (0.3, 0.3), when viewed from space or when the Sun is high in the sky. The Solar radiance per wavelength peaks in the green portion of the spectrum when viewed from space. When the Sun is low in the sky, atmospheric scattering renders the Sun yellow, red, orange, or magenta. Despite its typical whiteness, most people mentally picture the Sun as yellow; the reasons for this are the subject of debate. The Sun is a G2V star, with G2 indicating its surface temperature of approximately 5,778 K (5,505 °C, 9,941 °F), and V that it, like most stars, is a main-sequence star. The average luminance of the Sun is about 1.88 giga candela per square metre, but as viewed through Earth's atmosphere, this is lowered to about 1.44 Gcd/m2. However, the luminance is not constant across the disk of the Sun (limb darkening).
Motion and Location
The Sun lies close to the inner rim of the Milky Way's Orion Arm, in the Local Interstellar Cloud or the Gould Belt, at a distance of 7.5–8.5 kiloparsecs (24–28 kly) from the Galactic Center. The Sun is contained within the Local Bubble, a space of rarefied hot gas, possibly produced by the supernova remnant Geminga, or multiple supernovae in subgroup B1 of the Pleiades moving group. The distance between the local arm and the next arm out, the Perseus Arm, is about 6,500 light-years. The Sun, and thus the Solar System, is found in what scientists call the galactic habitable zone. The Apex of the Sun's Way, or the solar apex, is the direction that the Sun travels relative to other nearby stars. This motion is towards a point in the constellation Hercules, near the star Vega.
Within 32.6 ly of the Sun there are 315 known stars in 227 systems, as of 2000, including 163 single stars. It is estimated that a further 130 systems within this range have not yet been identified. Out to 81.5 ly, there may be up to 7,500 stars, of which around 2,600 are known. The number of substellar objects in that volume are expected to be comparable to the number of stars. Of the 50 nearest stellar systems within 17 light-years from Earth (the closest being the red dwarf Proxima Centauri at approximately 4.2 light-years), the Sun ranks fourth in mass.
The Sun is composed primarily of the chemical elements hydrogen and helium. At this time in the Sun's life, they account for 74.9% and 23.8% of the mass of the Sun in the photosphere, respectively. All heavier elements, called metals in astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%) being the most abundant. The Sun's original chemical composition was inherited from the interstellar medium out of which it formed. Originally it would have contained about 71.1% hydrogen, 27.4% helium, and 1.5% heavier elements. The hydrogen and most of the helium in the Sun would have been produced by Big Bang nucleosynthesis in the first 20 minutes of the universe, and the heavier elements were produced by previous generations of stars before the Sun was formed, and spread into the interstellar medium during the final stages of stellar life and by events such as supernovae.
Since the Sun formed, the main fusion process has involved fusing hydrogen into helium. Over the past 4.6 billion years, the amount of helium and its location within the Sun has gradually changed. Within the core, the proportion of helium has increased from about 24% to about 60% due to fusion, and some of the helium and heavy elements have settled from the photosphere towards the center of the Sun because of gravity. The proportions of metals (heavier elements) is unchanged. Heat is transferred outward from the Sun's core by radiation rather than by convection (see Radiative zone below), so the fusion products are not lifted outward by heat; they remain in the core and gradually an inner core of helium has begun to form that cannot be fused because presently the Sun's core is not hot or dense enough to fuse helium. In the current photosphere, the helium fraction is reduced, and the metallicity is only 84% of what it was in the protostellar phase (before nuclear fusion in the core started). In the future, helium will continue to accumulate in the core, and in about 5 billion years this gradual build-up will eventually cause the Sun to exit the main sequence and become a red giant.
The chemical composition of the photosphere is normally considered representative of the composition of the primordial Solar System. The solar heavy-element abundances described above are typically measured both using spectroscopy of the Sun's photosphere and by measuring abundances in meteorites that have never been heated to melting temperatures. These meteorites are thought to retain the composition of the protostellar Sun and are thus not affected by the settling of heavy elements. The two methods generally agree well.
Singly ionized iron-group elements
In the 1970s, much research focused on the abundances of iron-group elements in the Sun. Although significant research was done, until 1978 it was difficult to determine the abundances of some iron-group elements (e.g. cobalt and manganese) via spectrography because of their hyperfine structures. The first largely complete set of oscillator strengths of singly ionized iron-group elements were made available in the 1960s, and these were subsequently improved. In 1978, the abundances of singly ionized elements of the iron group were derived.
Various authors have considered the existence of a gradient in the isotopic compositions of solar and planetary noble gases, e.g. correlations between isotopic compositions of neon and xenon in the Sun and on the planets. Prior to 1983, it was thought that the whole Sun has the same composition as the solar atmosphere. In 1983, it was claimed that it was fractionation in the Sun itself that caused the isotopic-composition relationship between the planetary and solar-wind-implanted noble gases.
During early studies of the optical spectrum of the photo-sphere, some absorption lines were found that did not correspond to any chemical elements then known on Earth. In 1868, Norman Lockyer hypothesized that these absorption lines were caused by a new element that he dubbed helium, after the Greek Sun god Helios. Twenty-five years later, helium was isolated on Earth.
The photo-sphere is outermost layer of the Sun, it is only 500 km thick, which is basically nothing compared to the radius.
Sunspots, which emerge when the magnetic field breaks through the surface, end up here. As well as light, which is created form the energy present.
Solar flares shoot out of the photo-sphere, bursting ultraviolet, gamma rays, x-rays and radio rays everywhere, in outer space and on the planets. The planets are protected thanks to their atmosphere, except for Mercury, because it only has an exosphere and it's particles are blasted of by the Sun's energy and solar winds.
The Sun's convection zone extends from 0.7 solar radii (500,000 km) to near the surface. In this layer, the solar plasma is not dense enough or hot enough to transfer the heat energy of the interior outward via radiation. Instead, the density of the plasma is low enough to allow convective currents to develop and move the Sun's energy outward towards its surface. Material heated at the tachocline picks up heat and expands, thereby reducing its density and allowing it to rise. As a result, an orderly motion of the mass develops into thermal cells that carry the majority of the heat outward to the Sun's photosphere above. Once the material diffusively and radiatively cools just beneath the photospheric surface, its density increases, and it sinks to the base of the convection zone, where it again picks up heat from the top of the radiative zone and the convective cycle continues. At the photosphere, the temperature has dropped to 5,700 K and the density to only 0.2 g/m3 (about 1/6,000 the density of air at sea level).
The Sun is cool enough for convection to occur, and it is the main method for heat transfer. Due to this convection, "cells" appear on the visible surface, they're called convective cells.
The convective zone reaches depths of around 212,000 km and at depths like those, temperatures reach 200,000 °C. The temperature cools down due to the creation of light at the photo-sphere.
The Sun's magnetic field is generated here also.
The radiative zone and the convective zone are separated by a transition layer, the tachocline. This is a region where the sharp regime change between the uniform rotation of the radiative zone and the differential rotation of the convection zone results in a large shear between the two—a condition where successive horizontal layers slide past one another. Presently, it is hypothesized (see Solar dynamo) that a magnetic dynamo within this layer generates the Sun's magnetic field. The tachocline lies between the convective exterior and the radiative interior. Both of these rotate at rapidly different speeds, as the convective layer's rotation acts as a liquid, whilst the radiative zone's is exhibited as solid-body rotation.
Below the tachocline resides the radiative zone. In this zone, the energy generated by nuclear fusion in the core is turned into electromagnetic energy and moves outwards. From the core out to about 0.7 solar radii, thermal radiation is the primary means of energy transfer. The temperature drops from approximately 7 million to 2 million kelvins with increasing distance from the core. This temperature gradient is less than the value of the adiabatic lapse rate and hence cannot drive convection, which explains why the transfer of energy through this zone is by radiation instead of thermal convection. Ions of hydrogen and helium emit photons, which travel only a brief distance before being reabsorbed by other ions. The density drops a hundredfold (from 20 g/cm3 to 0.2 g/cm3) from 0.25 solar radii to the 0.7 radii, the top of the radiative zone.
Most stars have a radiative zone, for the Sun, it engulfs a majority (70%) of our star.
In the core of the Sun, nuclear fusion is very powerful and every single second, the Sun emits incredible amounts of energy, so much in fact, that this energy is actually much higher in amounts of all the energy that the entire human species has ever produced on planet Earth, from the very Beginning, since Adam and Eve / Eva. The temperature at the sun's core is around 15 million degrees Celsius (28 million degrees Fahrenheit), which is almost 3,000 time higher than at the surface. The core is 10 times as dense as gold or lead, and the pressure is 340 billion times the atmospheric pressure on Earth's surface. There are two distinct reactions in which four hydrogen nuclei may eventually result in one helium nucleus: the proton–proton chain reaction – which is responsible for most of the Sun's released energy – and the CNO cycle.
The core of the Sun extends from the center to about 20–25% of the solar radius. It has a density of up to 150 g/cm3 (about 150 times the density of water) and a temperature of close to 15.7 million kelvin (K). By contrast, the Sun's surface temperature is approximately 5800 K. Recent analysis of SOHO mission data favors a faster rotation rate in the core than in the radiative zone above. Through most of the Sun's life, energy has been produced by nuclear fusion in the core region through a series of nuclear reactions called the p–p (proton–proton) chain; this process converts hydrogen into helium. Only 0.8% of the energy generated in the Sun comes from another sequence of fusion reactions called the CNO cycle, though this proportion is expected to increase as the Sun becomes older.
The core is the only region in the Sun that produces an appreciable amount of thermal energy through fusion; 99% of the power is generated within 24% of the Sun's radius, and by 30% of the radius, fusion has stopped nearly entirely. The remainder of the Sun is heated by this energy as it is transferred outwards through many successive layers, finally to the solar photosphere where it escapes into space through radiation (photons) or advection (massive particles).
The fusion rate in the core is in a self-correcting equilibrium: a slightly higher rate of fusion would cause the core to heat up more and expand slightly against the weight of the outer layers, reducing the density and hence the fusion rate and correcting the perturbation; and a slightly lower rate would cause the core to cool and shrink slightly, increasing the density and increasing the fusion rate and again reverting it to its present rate. The core of our Sun is where nuclear fusion happens. It is also the hottest part of our Sun, reaching temperatures of 15,000,000 °C. The core accounts for 34% of the Sun's mass and has a density 20 times that of iron.In the core, hydrogen forms helium and He3 forms helium and hydrogen.
The Chromosphere is the lower portion of the Sun's atmosphere. It has a red color and reaches around 4000 kilometers above the surface. The density of the chromosphere is only 10−4 times that of the photosphere, the layer beneath, and 10−8 times that of the atmosphere of Earth at sea level. This makes the chromosphere normally invisible and it can be seen only during a total eclipse, where its reddish color is revealed. The color hues are anywhere between pink and red. Without special equipment, the chromosphere cannot normally be seen due to the overwhelming brightness of the photosphere beneath. The density of the chromosphere decreases with distance from the center of the Sun. This decreases exponentially from 1017 particles per cubic centimeter, or approximately 2×10−4 kg/m3 to under 1.6×10−11 kg/m3 at the outer boundary. The temperature decreases from the inner boundary at about 6,000 K to a minimum of approximately 3,800 K, before increasing to upwards of 35,000 K at the outer boundary with the transition layer of the corona
Here, filaments - solar prominiscenes, occur, caused again, by the magnetic field and the relatively cool gases above the photosphere.
The corona is the upper atmosphere, however, even though it is so far away and stretches out thousands of kilometers, its temperature is millions of degrees and the density drops rapidly.
In the corona, the magnetic field affects charged particles to form "lines". They can only be seen, as well as the chromosphere, during an eclipse when the photosphere doesn't obscure the rest of the light of the chromosphere and corona.
The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between 0.5 and 10 keV. The composition of the solar wind plasma also includes a mixture of materials found in the solar plasma: trace amounts of heavy ions and atomic nuclei C, N, O, Ne, Mg, Si, S, and Fe. There are also rarer traces of some other nuclei and isotopes such as P, Ti, Cr, Ni, Fe 54 and 56, and Ni 58,60,62. Embedded within the solar-wind plasma is the interplanetary magnetic field. The solar wind varies in density, temperature and speed over time and over solar latitude and longitude. Its particles can escape the Sun's gravity because of their high energy resulting from the high temperature of the corona, which in turn is a result of the coronal magnetic field.
At a distance of more than a few solar radii from the Sun, the solar wind reaches speeds of 250–750 km/s and is supersonic, meaning it moves faster than the speed of the fast magnetosonic wave. The flow of the solar wind is no longer supersonic at the termination shock. Other related phenomena include the aurora (northern and southern lights), the plasma tails of comets that always point away from the Sun, and geomagnetic storms that can change the direction of magnetic field lines. The Solar Wind, also called Solar Flare is a phenomenon when the Sun emits a lot of energy, and at that part of it's surface, brightness becomes higher and large amounts of radiation are emitted and blasted of though outer space. Data about the Solar winds have been gathered by NASA. Solar winds are very violent and they carry many ultra-violent rays, of radio-rays, x-rays and gamma-rays.
Solar winds damage the magnetic fields, ozone layers and atmospheres of planets, unfortunately, including Earth. Solar winds can destroys the magnetic fields and ozone layers of planets, killing every living organism if there is. Last time Earth was hit by a solar wind, a destruction occurred, First things first, the solar wind was small and weak and humans survived because they did not rely on technology, but now, everywhere something electric exists, and solar winds are gradually increasing in strength. These are very bad news, because if a solar winds hits Earth again, humans will live a nuclear apocalypse without technology, since all the panels, computers etc. will be destroyed and uselss, if a solar wind, even a very weak one hits Earth again.
Let's not forget about the Moon, Mars and Mercury. NASA claims that possible fossil of microbes exist on the surface of the Moon, Mars and Mercury. But the 3 of them have very thin atmospheres that are continuously blasted away by stellar winds of the Sun. Mars, Mercury and the Moon have no magnetosphere, neither an ozone layer, therefore, their surface is also prone to solar winds, especially the surfaces of the Moon and Mercury. Mars has a thin atmosphere for protection and is farther away from the Sun, so it is not as prone to Solar wind as Mercury and the Moon.
The solar wind is observed to exist in two fundamental states, termed the slow solar wind and the fast solar wind, though their differences extend well beyond their speeds. In near-Earth space, the slow solar wind is observed to have a velocity of 300–500 km/s, a temperature of ~100 MK and a composition that is a close match to the corona. By contrast, the fast solar wind has a typical velocity of 750 km/s, a temperature of 800 MK and it nearly matches the composition of the Sun's photosphere. The slow solar wind is twice as dense and more variable in nature than the fast solar wind.The slow solar wind appears to originate from a region around the Sun's equatorial belt that is known as the "streamer belt", where coronal streamers are produced by magnetic flux open to the heliosphere draping over closed magnetic loops. The exact coronal structures involved in slow solar wind formation and the method by which the material is released is still under debate. Observations of the Sun between 1996 and 2001 showed that emission of the slow solar wind occurred at latitudes up to 30–35° during the solar minimum (the period of lowest solar activity), then expanded toward the poles as the solar cycle approached maximum. At solar maximum, the poles were also emitting a slow solar wind.The fast solar wind originates from coronal holes, which are funnel-like regions of open field lines in the Sun's magnetic field. Such open lines are particularly prevalent around the Sun's magnetic poles. The plasma source is small magnetic fields created by convection cells in the solar atmosphere. These fields confine the plasma and transport it into the narrow necks of the coronal funnels, which are located only 20,000 km above the photosphere. The plasma is released into the funnel when these magnetic field lines reconnect.
The Sun was formed like most stars, through gas collisions and gravity. From the beginning, 4,603,000,000 years ago, large clouds of gasses were pressed together and through gravity clumping them and holding them together and making them spin around the middle, a protostar was formed. The protostar Sun was only a protostar, it was hydrogen and helium, but not yet ran by fusion, since as a nebula and even as a protostar, the core is not hot enough, it took 50 million years to become a normal star and the core to increase enough to cause thermonuclear fusion. What was left of the gas and materials, since there was much, later turned into planets the planets we know today: mercury, venus, earth, mars, jupiter, saturn, uranus and neptune, as well as pluto and many, many other dwarf planets.
The Fate of the Sun and of the entire Solar System, including planet Earth, is very long and tragic. The more hydrogen the Sun burns, the more energy is released and when this energy reaches the surface, the molecules are absorbed by the photosphere, and gradually, more and more are absorbed and radiated into space, causing the Sun to be brighter, and the star become brighter about 10 percent every 1 billion years.
- In 600 million years, Earth's temperature is thought to reach on average, around 70 °C. The increased luminosity will make more water on Earth evaporate, and increase the levels of silicon on the surface causing Co2 in the atmosphere to get lower, and photosynthesis will no longer be possible, causing 99 percent of the plants die in 800 million years.
- In 1.1 billion, the higher luminosity will cause the oceans to evaporate, causing a greenhouse effect that will make Earth's surface a desert.
- In 2.3 to 2.8 billion years, the luminosity will cause the temperatures to be 150 °C, even at the poles, causing all life to go extinct. This will go on for 3 - 4 billion years making Earth like Venus is today and even hotter, because of the larger mass and size of Earth, more rocks will be burned on the surface of the planet, causing the temperatures to reach 1.330 °C. The magnetosphere of Earth will have decayed by this time, since the core of Earth will have cooled down, causing radiation of the Sun to enter the atmosphere, making it even hotter at around 1.500 - 2.000 °C, as well as toxic, with active nuclear particles, nuclear waste and toxic nuclear wast with dirt and broken materials, ruining the atmosphere and the surface of Earth. Nothing will be able to survive. Earth will become the worst planet to support life, even worse than Venus and the gas giants, Jupiter, Saturn, Uranus and Neptune. Even the toughest microscopic organisms that can survive very extreme conditions, could not possibly exist on this future planet Earth.
- In 5.39 to 7.72 billion years, the Sun's hydrogen in the core will be completely depleted and the Sun will reach as to what is known the red giant phase of it's evolution. This will begin once all hydrogen is exhausted in the core and the inert helium ash that has built up there becomes unstable and collapses under its own weight. This will cause the core to heat up and get denser, causing the sun to grow in size. The outer layers of the Sun will grow, but the core will get smaller. First, the Sun was thought to reach 300,000,000 km in diameter but latest studies show that it will reach 1,000,000,000 km in diameter. All the planets will be pushed outward but the Sun will become so large that it will definitely devour the planet Mercury, incredibly high, nearly 100% chance to devour Venus and the Sun will likely also devour Earth. Mars was also thought to be devoured, but after research, it's clear that Mars will survive. However, all the planets will get very hot, even Uranus and Neptune. Many moons and dwarf planets will also have liquids, including water, on their surfaces.
- Finally, when all the helium will be depleted, the star will become completely unstable, causing the outer layers to be lost in a planetary nebula. What will remain will be the Sun's core , a white dwarf, with about 45 percent of the previous solar mass, but the size will be around that of Earth, or slightly smaller. After trillion of years, the white dwarf will become cool and dark, a black dwarf. Then the Sun's journey will have ended, never to shine again. By this time, humanity will either cease to exist, OR will be thriving on a distant planet, reading about the Sun, the small star that started it all...........