Here's why:
* High Temperature: White dwarfs are incredibly dense and hot, with surface temperatures reaching tens of thousands of degrees Celsius.
* Small Size: They are much smaller than our Sun, often only the size of a planet. This small size means they have a much lower surface area compared to larger stars.
* Low Luminosity: While they are incredibly hot, their small size means they have a very low luminosity (total energy output). This makes them appear dim, even though they are burning at extremely high temperatures.
In essence, the reason they appear dim is because they are so small, even though they are incredibly hot.
