User:JonathanHopeThisIsUnique/Sandbox
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I want to translate the English Wikipedia page about the Sun into Simple English. The page already exists in the Simple English Wikipedia, but it is missing much of the information that is available in the English Wikipedia. Therefore, I've decided to start over by copying the most recent version from the English Wikipedia, as of now. I'll then edit it to make it follow Simple English Wikipedia guidelines.
Observation data | |
---|---|
Mean distance from Earth | 1 au ≈ 1.496×108 km[1] 8 min 19 s at light speed |
Visual brightness (V) | −26.74[2] |
Absolute magnitude | 4.83[2] |
Spectral classification | G2V[3] |
Metallicity | Z = 0.0122[4] |
Angular size | 31.6–32.7 minutes of arc[5] |
Adjectives | Solar |
Orbital characteristics | |
Mean distance from Milky Way core | ≈ 2.7×1017 km 27,200 light-years |
Galactic period | (2.25–2.50)×108 yr |
Velocity | ≈ 220 km/s (orbit around the center of the Milky Way) ≈ 20 km/s (relative to average velocity of other stars in stellar neighborhood) ≈ 370 km/s[6] (relative to the cosmic microwave background) |
Physical characteristics | |
Equatorial radius | 695,700 km,[7] 696,342 km[8] 109 × Earth[9] |
Equatorial circumference | 4.379×106 km[9] 109 × Earth[9] |
Flattening | 9×10−6 |
Surface area | 6.09×1012 km2[9] 12,000 × Earth[9] |
Volume | 1.41×1018 km3[9] 1,300,000 × Earth |
Mass | 1.9885×1030 kg[2] 333,000 × Earth[2] |
Average density | 1.408 g/cm3[2][9][10] 0.255 × Earth[2][9] |
Center density (modeled) | 162.2 g/cm3[2] 12.4 × Earth |
Equatorial surface gravity | 274 m/s2[2] 28 × Earth[9] |
Moment of inertia factor | 0.070[2] (estimate) |
Escape velocity (from the surface) | 617.7 km/s[9] 55 × Earth[9] |
Temperature | Center (modeled): 1.57×107 K[2] Photosphere (effective): 5,772 K[2] Corona: ≈ 5×106 K |
Luminosity (Lsol) | 3.828×1026 W[2] ≈ 3.75×1028 lm ≈ 98 lm/W efficacy |
Color (B-V) | 0.63 |
Mean radiance (Isol) | 2.009×107 W·m−2·sr−1 |
Age | ≈ 4.6 billion years[11][12] |
Rotation characteristics | |
Obliquity | 7.25°[2] (to the ecliptic) 67.23° (to the galactic plane) |
Right ascension of North pole[13] | 286.13° 19 h 4 min 30 s |
Declination of North pole | +63.87° 63° 52' North |
Sidereal rotation period (at equator) | 25.05 d[2] |
(at 16° latitude) | 25.38 d[2] 25 d 9 h 7 min 12 s[13] |
(at poles) | 34.4 d[2] |
Rotation velocity (at equator) | 7.189×103 km/h[9] |
Photospheric composition (by mass) | |
Hydrogen | 73.46%[14] |
Helium | 24.85% |
Oxygen | 0.77% |
Carbon | 0.29% |
Iron | 0.16% |
Neon | 0.12% |
Nitrogen | 0.09% |
Silicon | 0.07% |
Magnesium | 0.05% |
Sulphur | 0.04% |
The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma,[15][16] with internal convective motion that generates a magnetic field via a dynamo process.[17] It is by far the most important source of energy for life on Earth. The diameter of the Sun is about 1.39 million kilometers (864,000 miles), or 109 times that of Earth. The mass of the sun is (add number). This is about 330,000 times the mass of Earth. The Sun accounts for about 99.86% of the total mass of the Solar System.[18] 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 oxygen, carbon, neon, and iron.[19]
The Sun is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion[lower-alpha 1][11][20] years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.
The Sun currently fuses about 600 million tons of hydrogen into helium every 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 from its 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. This will eventually transform the Sun into a red giant. It is calculated that the Sun will become big enough to engulf the current orbits of Mercury and Venus, and render Earth uninhabitable – but not for about five billion years. After this, the Sun will shed its outer layers and become a dense type of cooling star known as a white dwarf. After the Sun becomes a white dwarf, it will no longer produce energy by fusion. But it will still glow and give off heat from its previous fusion.
The enormous effect of the Sun on Earth has been recognized since prehistoric times, and the Sun has been regarded 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 the most commonly used calendar today.