Answer:
A hotter star should be brighter than a cooler star. ... Although they are cool [red], they are very luminous, and therefore bright. In the Main Sequence, stars that are cool are not as luminous. Because the energy is spread across a larger area, surface temperatures are actually cooler, reaching only 2,200 to 3,200 degrees Celsius (4,000 to 5,800 degrees Fahrenheit), a little over half as hot as the sun
Explanation:
