Here's why:

* Wien's Displacement Law: This law states that the wavelength at which a blackbody emits most of its radiation is inversely proportional to its temperature. So, cooler objects emit at longer wavelengths.

* Infrared Radiation: Infrared radiation has longer wavelengths than visible light.

Since 3000 K is relatively cool for a star (our Sun is about 5800 K), its peak emission falls within the infrared part of the electromagnetic spectrum.