A star with a surface temperature above 30,000 degrees Celsius would be blue.

Here's why:

* Star Color and Temperature: A star's color is directly related to its surface temperature. Hotter stars emit more blue light, while cooler stars emit more red light.

* Blue Stars: Stars with surface temperatures above 30,000 degrees are considered "blue" stars. They are the hottest and most massive stars, and they often have very short lifespans.

Let me know if you have any more questions about stars!