NASA/GSFC/AIA
It’s pretty safe to say mankind has known about the Sun since, well, there was mankind. It’s by far the brightest object in the sky, with an apparent magnitude of -26.7; that’s about 400,000 times brighter than the Full Moon. It’s also the biggest object in the local area by far — it makes up 99 percent of the material in the solar system. And, as anyone who’s ever spent a long day outdoors knows, the Sun is almost incomprehensibly hot: Its surface temperature is about 9900° Fahrenheit (5500° Celsius).
Learn more about our hom star by registering with Astronomy.com and gaining access to the video, “Tour the solar system: The Sun.”