At the core of the sun, gravitational attraction produces immense pressure and temperature, which can reach more than 27 million degrees Fahrenheit (15 million degrees Celsius).

The Sun is mostly composed of hydrogen (70%) and Helium (28%).

If you were to fill a hollow Sun with spherical Earths, somewhere around 960,000 would fit inside. However, if you squashed those Earths to ensure there was no wasted space then you could fit 1,300,000 Earths inside the Sun.

It takes sunlight an average of 8 minutes and 20 seconds to travel from the Sun to the Earth.

The Sun is a main-sequence G2V star or Yellow Dwarf.

At 4.5 billion years old, the Sun has burned off around half of its hydrogen stores and has enough left to continue burning hydrogen for another 5 billion years.

Scientists classify strong solar flares into one of three categories: C, M or X (with A and B classes, too, for weaker eruptions). There's a tenfold increase in power from one class to the next, so an X flare is 10 times stronger than an M flare, and 100 times more powerful than a C.

Aristarchus of Samos was an ancient Greek astronomer and mathematician who presented the first known heliocentric model that placed the Sun at the center of the solar system with the Earth revolving around it. He was influenced by Philolaus of Croton, but Aristarchus identified the "central fire" with the Sun, and he put the other planets in their correct order of distance around the Sun.

The sun's magnetic field changes polarity approximately every 11 years: its north magnetic pole becomes a south pole, and vice versa.

The sun's gravity is 28 times stronger than the force of gravity on the Earth, so a person weighing 150 pounds on Earth would weigh 4,200 pounds on the sun.