Some 'dead' stars hide celestial fountains of youth beneath their surfaces

Two alternative models for the interior of white dwarfs placed side-by-side. The stars look like large blue orbs; there are arrows denoting where certain layers and processes are.

White dwarfs are the stars that will be left behind when stars like the sun "die," smoldering away in space as cooling stellar embers.

Recent observations indicated that some of these stellar corpses may actually take longer to cool off than previously expected. This means that white dwarfs may have a way of generating energy after their "deaths," defying the classical picture of them being inert dead stars. As a result, some white dwarfs could actually be billions of years older than currently estimated.