The Sun

The Sun is a main sequence star which means that it is one of the largest & brightest stars. The sun is approximately 500k on the surface & about 15,600,000, k stands for Kelvin which is absolute zero water melts at 273k & boils at 373k. It is about 1, 390,000 km in diameter & 1.989e30 kg, e stands for sexponential notation ex. (123.e4=1.23* 10 to the fourth power, which makes it the largest object in the solar system. The sun also contains more than 98.8% of the mass of the entire solar system. The sun is personified by many mytholigies Greeks called it Helios & the Romans called it Sol. The sun is about 70% hydrogen, 28% helium, everything else is mostly metals is 2%.  The suns outer layers exhibit what scientist call differential rotation, at the equator of the sun it rotates every 25.4 days; near the poles it’s as much as 36 days. The defferential rotation is caused by the fact that the sun unlike earth is not a solid body it is mostly gas & molten metals, similar effects happen in the gas planets like jupiter & saturn. The suns’ core is 15.6K & the pressure 250 billion atmospheres & its density is  more than 150 times that of water. The sun produces 386 billion billion megawatts which is produced by nuclear fusion reactions. Each second about 700,000,000 tons of hydrogen are converted to about 695,000,000 & 5,000,000 tons of energy  absorbed from from gamma rays. The surface of the sun is called the photosphere. The photosphere is about 5800k. There are cool regions on the suns surface called sunspots. Sunspots measure at about only 3800k. Sunspots are darker than surrounding regions of the surface & can be as much as 50,000 km in diameter. Sunspots are caused by interactions with the suns magnetic field. The chronosphere is a small region above the photosphere & the region above that is called the carona. The carona extends millions of killometers into space but can only be seen during a full solar eclipse. Temperatures in the carona are over 1,000,000k. The suns magnetosphere is called the heliosphere. The suns heliosphere extends far beyond pluto. In addition to heat & light the sun also emits a low density stream of charged electron & ptotons otherwise known as the solar wind. Solar wind flows through the solar system at about 450km/sec. The solar wind has large effects on the tails of comets.The Sun is about 4.5 billion years old. Since its birth It has used up half the hydrogen in its core. It will continue to radiate peacefuly for another 5 billion years or so.