The Greeks named the sun Helios, but the Romans used the name Sol, which is still in use today. Due to the important role the sun plays in our lives, it has been studied, perhaps, more than any other object in the universe, outside our own planet Earth.
The Sun is the closest star to Earth. It is by far the largest object in the solar system, and contains more than 99.8% of the total mass of the Solar System (Jupiter contains most of the rest). Its strong gravitational pull holds Earth and the other planets in the solar system in orbit.
Our Sun is considered to be an average star, meaning its size, age, and temperature fall in about the middle of the ranges of these properties for all stars. It is only 4.6 billion years old. Some of its material came from former stars.
This image, "Handle-shaped Prominence", Extreme Ultraviolet Imaging Telescope (EIT) image of a huge, handle-shaped prominence taken on Sept. 14,1999. Prominences are huge clouds of relatively cool dense plasma suspended in the Sun's hot, thin corona. At times, they can erupt, escaping the Sun's atmosphere. Emission in this spectral line shows the upper chromosphere at a temperature of about 60,000 degrees K. The hottest areas appear almost white, while the darker red areas indicate cooler temperatures.
Let's head outward from the sun to the first planet in our solar system, Mercury.
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