The Solar System Wiki

Reminder to always post your discussions posts in the right category! Lots of new art posts are showing up in the wrong place!

READ MORE

The Solar System Wiki
Register
Advertisement
It has been considered that this page be moved to "The Sun".
Discuss your opinion on this talk page. The main reason for this move is the designation "Sun" is more commonly used. Please do not remove this tag or move the page until the discussion has been concluded.
This page/section is long
This page may cause lag to those using devices with low RAM or bad internet.
Be careful scrolling quickly, as your device may freeze or crash.
These reasons may also make editing difficult.
This page currently is 15,850 bytes in size.
Sol
SolTrueColour
True-color image taken in 2019 using a solar filter
Date of Discovery Antiquity
Atmospheric Makeup Hydrogen and Helium
Distance from Sun 94.4 million miles from Earth (1 astronomical unit)
Diameter 1,392,678 kilometers
Axial tilt 23.5 degrees
Surface Features Barley-like surface texture with sunspots
Mass of Planet 1.989 × 10^30 kg

The Sun (sometimes known as Sol) is an average sized G-type main sequence star or a yellow dwarf located at the center of the Solar System.

It is 1.3 million km in diameter and is 94 million miles (or 1 astronomical unit) to Earth in distance. It is 1.989 × 10^30 kg in mass, or a million times more dense than the Earth and a thousand times more dense than Jupiter. Because of its massive gravity, it is able to keep all the objects in the Solar System in a stable orbit.

The Sun’s surface burns at a temperature of 5504 degrees Celsius and its core boils at a temperature of 15 million degrees Celsius. The reason the Sun emits so much heat is because of the nuclear fusion power that fuses hydrogen into helium in its core, allowing it to release extra energy and emit serious amounts of light and heat. This keeps the star in a stable state and position, but will not last long. Every second, The Sun's core fuses about 600 million tons of hydrogen into helium, and in the process converts 4 million tons of matter into energy. 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 hydrostatic 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 possibly Earth, and rendering Earth unhabitable in 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 fusion.

The enormous effect of the Sun’s effect on Earth has been recognized since prehistoric times. The star itself was thought of by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of some solar calendars. The predominant calendar in use today is the Gregorian calendar which is based upon the standard 16th-century interpretation of the Sun's observed movement as actual movement.

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, ancient Greek ἥλιος (hēlios), Welsh haul and Czech slunce, 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 sol, Icelandic sól, etc.

The principal adjectives for the Sun in English are sunny for sunlight and, in technical contexts, solar (/ˈsoʊlər/), from Latin the Sun – the latter found in terms such as solar day, solar eclipse and Solar System (occasionally the Sun system). From the Greek helios comes the rare adjective heliac (/ˈhiːliæk/). In English, the Greek and Latin words occur in poetry as personifications of the Sun, Helios (/ˈhiːliəs/) and the Sun (/ˈsɒl/), while in science fiction the Sun may be used as a name for the Sun to distinguish it from other stars. The term the Sun with a lower-case s is used by planetary astronomers for the duration of a solar day on another planet such as Mars.

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 ancient Greek ἡμέρα ἡλίου (hēmera hēliou) 'day of the sun'. The astronomical symbol for the Sun is a circle with a center dot, . It is used for such units as M (Solar mass), R (Solar radius) and L (Solar luminosity).

General characteristics

The Sun is a G-type main-sequence star that constitutes 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 (by about +/- 2.5 million km or 1.55 million miles) as Earth moves from perihelion on about 03 January to aphelion on about 04 July. The distances can vary between 147,098,074 km (perihelion) and 152,097,701 km (aphelion), and extreme values can range from 147,083,346 km to 152,112,126 km. At its average distance, light travels from the Sun's horizon to Earth's horizon in about 8 minutes and 20 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.

Atmosphere

The Sun’s atmosphere is called the corona. The corona can only be seen during an eclipse. The corona is one trillion times less dense than the photosphere, yet it can reach three million degrees Celsius. It extends millions of miles into space. Though the corona is the main atmosphere, before it is what is known as the transition region, the point at which the temperature transitions from the hotter parts of the photosphere, which is 36,000 degrees Fahrenheit, to the corona, reaching 1.8 million degrees Fahrenheit.

Phases of Life

The Sun formed from at the center of the rotating disk of materials that was once known as the Solar Nebula.

The Sun firstly formed as a Brown Dwarf and then later a T-Tauri Star, then entered Main Sequence as it gained enough mass for fusing hydrogen into helium.

In around 5 billion years, the Sun's core will get exhausted of hydrogen and enter a subgiant phase, where the Sun enlarges its size of about 3 ~ 10 times its current diameter. In around 7.8 billion years, the Sun will enter a red giant phase and engulf Mercury, Venus, and possibly the Earth's orbit and vaporize the entire three planets. After engulfing Earth's orbit, the Sun will start experiencing thermal pulsations and cause massive coronal mass ejections, blowing off 25% of the Jupiter's mass into outer space and possibly vaporizing Mars's outer crust.

Once enough mass is gone, the Sun will start shrinking and eventually detach all of its atmosphere, leaving them as a planetary nebula that would stretch into the interstellar bubble. The final remains of the Sun will be its former core, a white dwarf, which is the size of Earth's diameter but being half of the Sun's normal density. It will stay as a white dwarf for around a trillion years, until its final energy source has disappeared, leaving the Sun as a black dwarf. This will destabilize the orbits of all the planets in the Solar System and most likely eject the Kuiper belt and the ice giants.

The Sun will transform into an iron star, if protons don't decay.

Comet Impacts

609px-Comet ISON (C-2012 S1) by TRAPPIST on 2013-11-15

When a comet gets close to the Sun, the ice will start to melt with particles and dust. Then these particles make a cloud called the coma.

A comet called Skara-0A99 smashed into the Sun in 2014, it burned and broke into 55 pieces. Then, a series of 32 explosions occurred, that passing comet was sucked into the sunspot.

Phenomena

Solar Flares

350px-171879main LimbFlareJan12 lg

A solar flare.

Solar flares are outburst of flames from solar wind, which can reach speeds one million kilometers per second. Solar flares release an abundance of radiation to the Earth, sometimes knocking out powerlines and causing power outages. Solar flares can reach extend one hundred thousand miles from the surface of the Sun. Solar wind is one cause of the extent due to the escape velocity of the Sun being 55 times the Earth's.

Prominences

A prominence is an outburst of plasma from the photosphere, extending into the upper corona. No one is sure exactly how these prominences are formed, yet these can extend for thousands of miles across the surface of Sol. Sometimes, these prominences can form in front of the Sun. They are then referred to solar filaments. These can last for weeks and can cause coronal mass ejections.

Sunspots

A sunspot.

Sunspots

Sunspots are small dark patches, or black areas, or dark areas on the surface of the Sun, which marked strong pockets of magnetism. They are also places where the surface is slightly cooler. These occur due to magnetic activity that reduces the surface temperatures. These occur only once every eleven years. These spots can spread to be 50,000 miles in diameter. The inner cooler part of a sunspot is called umbra. The outer, paler part is called the penumbra. One Of These Sucked In A Comet That Flew Too Close, The structure of sunspots are granule, penumbra, and umbra. Galileo and the German Jesuit Christoph Scheiner each saw them in 1611, and vied bitterly in their lifetimes over who deserved the credit for discovering them. Thomas Harriot, of course, was very likely the first person to see sunspots through a telescope in December 1610. Sunspots can be as big as the Earth.

Solar Wind

Solar wind is the outburst of energized particles that can shoot off into space. These particles can reach speeds of over one million miles per hour. When these particles collide with atoms in the Earth's atmosphere, the aurorae light show is then formed.

Coronal Mass Ejections

A coronal mass ejection (CME) is an outburst of plasma from the Sun that is heading out into space. These mass ejections can reach speeds of seven million miles per hour. These can be caused by prominences and solar flares. During a solar maximum, which is the time when an eleven-year process is at its peak of occurrences, up to five ejections can happen in one day. When these collide with Earth's atmosphere, they can cause aurorae that are very strong. They can even possibly interfere with radio communication devices.

Solar quake

A solar quake.

Solar Quakes

A solar quake is a series of waves that travel across the photosphere of the Sun after a previous solar flare. These waves are clearly visible through space telescopes. They appear as a ripple in a pond, yet they can reach to be four miles high. They can even extend to be eighty thousand miles long. They can even reach speeds of two hundred thousand miles per hour.

Miscellaneous Active Regions

When prominences are viewed in front of Sol, they are called solar filament. This makes it appear darker than the surrounding area. Spicules are short-living jets of gas that appear on the surface of Sol.

the Sun doesn't have volcanoes.

Granulation

Granulation occurs when Sol’s photosphere appears to be sandy or mottled, hence the name "granulation". This occurs from convection currents of plasma in the convection zone of the Sun. The heads of these convective cells appear grainy and this causes the photosphere to appear to have granules.

Layers

Structure sun spacepedia

The interior of the sun.

Photosphere

The visible surface of Sol. This layer can reach to be ten thousand degrees Celsius.

Convective Zone

The convective zone is the layer beneath the photosphere. This layer is where the convection currents occur. Hot gas bubbles fall due to them being less dense than the surrounding air, so they rise. Then, after rising and becoming cooled, they become dense and then sink. This causes the photosphere appear to be boiling.

Radiative zone

The next layer is the radiative zone, a zone where heat from Sol’s core is radiated to the convective zone. Radiation is the process at which heat is transmitted from one object to another.

Core

The core is the last layer of Sol, making up only two percent of Sol’s volume, yet making up 60% of its mass. This is also where photons, tiny packets of energy, are released, yet they take one hundred thousand years to travel to the photosphere. The core of Sol’s temperature is 27,000,000°F (15,000,000°C).

Orbit around the Milky Way

The Solar System orbits the Milky Way Galaxy once every 230 million years or so.

Observing the Sun

Solar filter front

A solar filter.

You may only view the Sun with a telescope fitted with solar filters. These help reduce the amount of light that enters the telescope. The filters also tint the light, so it isn't pure white, yet be careful observing the Sun during an eclipse. Do not look at it directly without the protection of these filters or a pair of goggles. If you cannot find or afford filters, place a piece of cardboard in front of the main eye of the telescope. Take this telescope on the right for example.

Gallery

the Sun is the brightest, biggest and hottest object in the Solar System.

Pictures

Advertisement