In 1974, the British physicist Stephen Hawking discovered that black holes have a characteristic
temperature and are therefore capable of emitting radiation. Given the scientific importance of this
discovery, there is a profuse literature on the subject. Nevertheless, the available literature ends
up being either too simple, which does not convey the true physical significance of the issue, or
too technical, which excludes an ample segment of the audience interested in science, such as
physics teachers and their students. The present article seeks to remedy this shortcoming. It
develops a simple and plausible argument that provides insight into the fundamental aspects of
Hawking’s discovery, which leads to an approximate equation for the so-called Hawking temperature .
The exposition is mainly intended for physics teachers and their students, and it only requires
elementary algebra, as well as basic notions of Newtonian mechanics and quantum theory.