By using this equation, we can determine just how BRIGHT (in an absolute sense) the thermal object is, that is, how many Watts / m² of light (power) is coming from this object. As the temperature INCREASES, the power INCREASES. But it does so very rapidly: by the FOURTH power of the temperature. As you turn UP the temperature even just a little bit on the stove, it also gets much much brighter (see below).

A few example calculations:

• If the stove is currently 300 K, how bright in W/m² is the center of the oven?





• If a star has a surface brightness of 9 x 10⁵ W/m², what must be the surface temperature of the star?





• If I increase the stove to twice the temperature, how much brighter is infrared light coming from the oven?