- Which is hotter at its surface: a red star or a blue star?
- Blue—these stars can burn at 90,000 degrees F (50,000 degrees C), making them the hottest suns in the cosmos. Red stars, on the other hand, are the coolest, with surface temperatures as low as 4,000 degrees F (2,200 degrees C) and ranging up to about 5,800 degrees F (3,200 degrees C). A star's color is determined by the levels of light it produces, and the spectrum goes from low-energy red to yellow to white to high-energy blue. The sun's surface temperature is about 11,000 degrees F (6,000 degrees C), making it a middle-of-the-road white-yellow star.
See what we're tweeting about
