ET's Waste Heat

So far, our efforts at finding technological civilizations among the stars have focused largely on searching for intelligent radio signals and virtual twins of Earth.  There are other approaches to pursue, however.

One such approach rests on the fact of physics that a civilization based on advanced technology will produce copious amounts of waste heat.  That heat will present itself as infrared radiation.  Unless that signature is masked in some way, the infrrared radiation would be detectable by our largest telescopes from a reasonable distance.  Such a finding around a Sun-like star, added to radio signals, for example, would make a powerful case for ET.