The Sun is the star at the center of the Solar System around which the Earth and other planets orbit.
45% of Americans are unaware that the sun is a star.
The Ancient Greeks portrayed the god Helios as driving the chariot of the sun across the sky each day to earth-circling Oceanus and through the world-ocean back to the East at night.
The Trundholm sun chariot pulled by a horse (below) is a sculpture believed to be illustrating an important part of Nordic Bronze Age mythology. The sculpture is probably from around 1350 BC.
It was the Greek philosopher Anaxagoras who suggested that the Sun is not the chariot of the god Helios.
Anaxagoras was also the first to explain that the Moon shines with light reflected from the Sun.
Recent research suggests that the first recorded observation of a sunspot may date back to ancient China. According to the Book of Han, an official history of the Han Dynasty, Chinese astronomers made an intriguing observation in 28 BC. On May 10 of that year, they documented that "the sun was yellow at its rising and a black vapor as large as a coin was observed at its center."
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| The Sun by By Geoff Elston - Society for Popular Astronomy |
45% of Americans are unaware that the sun is a star.
HISTORY
The Ancient Greeks portrayed the god Helios as driving the chariot of the sun across the sky each day to earth-circling Oceanus and through the world-ocean back to the East at night.
The Trundholm sun chariot pulled by a horse (below) is a sculpture believed to be illustrating an important part of Nordic Bronze Age mythology. The sculpture is probably from around 1350 BC.
 |
| By Nationalmuseet, Wikipedia |
It was the Greek philosopher Anaxagoras who suggested that the Sun is not the chariot of the god Helios.
Anaxagoras was also the first to explain that the Moon shines with light reflected from the Sun.
Recent research suggests that the first recorded observation of a sunspot may date back to ancient China. According to the Book of Han, an official history of the Han Dynasty, Chinese astronomers made an intriguing observation in 28 BC. On May 10 of that year, they documented that "the sun was yellow at its rising and a black vapor as large as a coin was observed at its center."
LOCATION AND SIZE
The Sun is by far the largest entity in the solar system containing 99.8% of its total mass.
The Earth could fit on the sun one million times over.
The Sun completes an orbit of the Milky Way galaxy about once every 225 million years.
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| Illustration of the Milky Way, showing the location of the Sun |
On this orbit, it travels at a speed of about 220km (140 miles) per second.
The Sun is 20 “years” old- it's completed 20 orbits around our galaxy's center since it first sparked to life.
The Sun is 400 times further from the Earth than the Moon, but the Moon is 400 times smaller than the Sun, making the two bodies appear the same size in the sky.
If you could drive from Earth to the Sun constantly at 75 mph, it would take about 141 years.
COMPOSITION
The Sun is made up of about a billion billion billion tonnes of mostly hydrogen gas.
Although the surface temperature of the Sun is approximately 5,778 K (5,505 °C, 9,941 °F), its core can reach 15,000,000 °C.
The surface of the sun, contains cell-like “kernels,” each about the size of Texas, that carry heat from inside the sun to the outside.
The reason the Sun is hot is that it contains a lot of mass. All that mass weighing down on the core squeezes it and makes it very hot.
The sun's atmosphere — a.k.a. the corona — is over 20 times hotter than the solar surface and scientists have no concrete explanation why.
CHARACTERISTICS
The Sun is the most perfectly round natural object known in the universe. It is so round that its polar diameter differs from its equatorial diameter by only 10 kilometres (6.2 mi). Its near-perfect sphere is because the Sun is a giant ball of gas, and gravity pulls all of the gas towards the center of the Sun. The Sun's rotation also helps to keep it round. As the Sun rotates, it bulges out slightly at the equator, but this bulge is very small.
The Sun's round shape is important because it helps to keep the Sun stable. If the Sun were not round, it would be more likely to collapse under its own gravity. The Sun's round shape also helps to distribute its heat evenly throughout the solar system.
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| Taken by Hinode's Solar Optical Telescope on 12 January 2007 |
The sun loses about 6 million tons of mass every second due to nuclear fusion and the solar wind. Despite losing that much material, it has only lost about 0.05% of it's original mass over the past 4.5 billion years.
It takes light from the sun approximately 8 minutes and 20 seconds to reach Earth.
The color of the Sun is a composite of all visible frequencies of light which makes it perfectly white. We see it yellow because of the Earth's atmosphere. In space the sun looks white.
The Sun produces a roar so loud that, if space were to be filled with air, it would create a sound of 125dB on Earth; 92.96 million miles away: around the volume of a jackhammer.
For perspective: a sound of 130dB would cause physical pain.
The sun's core is so hot that a piece of it the size of a pinhead would give off enough heat to kill a person 160 kilometres (99 miles) away.
Even the coolest places on the Sun's surface are hot enough to melt every compound that humans have ever found or created.
Sunbeams, or crepuscular rays, are always parallel to each other—they just look like they're meeting at the sun because of perspective.
Most stars exist in binary or triple star systems. It is hypothesized that up to 85% of stars are gravitationally bound to another star in a multiple star system. Therefore, solitary stars (such as the Sun) are actually not the norm in the universe.
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