Glowing Aliens 
WRIGHT: We are looking for the waste heat from alien civilizations with very, very large energy supplies.
A few years ago, a space telescope known as WISE mapped the sky at infrared wavelengths. It cataloged more than 500 million objects that emit much of their energy in the form of heat — the infrared — from asteroids and comets in our own solar system to distant galaxies. Penn State astronomer Jason Wright is looking for evidence of something else in the WISE catalog: alien life. He discussed it during a recent conference.
WRIGHT: Alien civilizations generate energy, or they capture starlight to do whatever alien civilizations do. When they’re done with it they have to get rid of it, the same way that when your computer’s done with its electricity, it’s got to have a fan to get rid of all that energy as heat. We are using the WISE satellite...to look for the traces of that heat coming from stars and galaxies that might have alien civilizations around them.
Wright and his colleagues are looking for stars or galaxies that are unexpectedly bright in the infrared. The extra energy is likely to come from clouds of dust. Yet some especially bright sources could be star-encircling structures built by alien life.
WRIGHT: We don’t have anything that I’m super excited about yet. We definitely have candidates where we don’t know that it’s dust — we don’t have any obvious indication that it’s dust, so those we will follow up. As scientists, we always reach for nature first. Aliens are the conclusion of last resort.
Even so, it’s possible that other civilizations could reveal their presence not with a phone call, but through the warm glow of their technology.
Script by Damond Benningfield, Copyright 2014