Re: How hot is the Sun?

Nobody can get close enough to the sun to dip a thermometer into it.

But...

The color of the sun, or of any star for that matter, gives scientists an idea of how hot it is. It's the same way a blacksmith can tell how hot his metal is by how much it is glowing. If it is dull red, it is much cooler than if it is bright orange.

Scientists have calculated that a star that glows yellow, like the Sun does, is about 5500 to 5700 degrees Celsius (about 10,000 Farenheit).

Although on a summer day on the beach, it often feels hotter than that!

Added by the astronomy moderator:

Note that by looking at the color, one measures the surface temperature of the Sun. The inside of the Sun is much hotter and one can calculate that the temperature peaks around 15 million degrees Celsius at the very center. It is at that location that the nuclear energy that makes the Sun glow is released by fusing atoms of hydrogen into helium.