The Sun accounts for about 99.86% of the total mass of the Solar System.
The Sun formed about 4.6 billion years ago from the collapse of part of a giant molecular cloud that consisted mostly of hydrogen and helium.
The beautiful symmetry of a total solar eclipse happens because —by pure chance— the sun is 400 times larger than the moon, but is also 400 times farther from Earth, making the two bodies appear the exact same size in the sky.
The theory that the Sun is the center around which the planets orbit was first proposed by the ancient Greek Aristarchus of Samos in the 3rd century BC.
The Sun does not have a definite boundary, and in its outer parts, its density decreases exponentially with increasing distance from its center.
1.3 millionEarths could fit inside the sun, an average-sized star.