Taking the Sun’s temperature The core of the Sun is an amazing 15 million degrees Celsius (27 million degrees Fahrenheit). The photosphere is only about 6000 °C (10,000 °F), but moving upward through the chromosphere, temperatures increase dramatically. The corona (the Sun’s extended outer atmosphere) has temperatures of 1-2 million degrees and produce a type of light called X-rays. Scientists still do not what heats the corona. Solar fingerprints: How we observe the Sun’s features and regions There's more to the Sun than meets the eye. Every object in the universe that emits radiation has its own electromagnetic spectrum. Each spectrum is unique, like a fingerprint.