Next we decided that maybe we should listen as well as look. We built radio telescopes to scan the stars to see if we could hear our extraterrestrial counterparts. To date, we have been unable to confirm an alien presence in the Universe. However, once again, science has not stalled in its search for E.T. This time, not only will we look and listen, but we will attempt to detect the heat emitted by an advanced alien civilization.
The process of alien heat detection has been proposed and studied by researchers J. T. Wright, B. Mullan, S. Sigurdsson, and M. S. Povich and was published in The Astrophysical Journal in June of this year (2014).
Unfortunately, news of the study was reported with very little fanfare and was barely given a mention in OuterPlaces.com. Though small, the write-up did look at the study in a positive light. Franck Marchis of the SETI Institute (who is unaffiliated with the project) told OuterPlaces:
“I like it because it doesn’t put any constraints on the origin of the civilization or their willingness to communicate.” (1)
Meaning, when you are looking for heat instead of radio waves, or other forms of communication, then you remove that need for the aliens to have built technologies that we would recognized. This technique looks only at the heat that would be emitted by a technologically advanced civilization.
Current Technology Drawbacks
Even though looking for heat eliminates that one drawback, the current methodology limits what researchers can actually detect. Like most of the current technologies used in the search for extraterrestrial life, this particular methodology (known as Glimpsing Heat from Alien Technologies survey or G-HAT) will only be able to detect technologically advanced civilizations that have a sizable energy supply. According to the study:
“We extend this argument to the growth of an ETI’s total energy supply, and show that it implies that very old, large ETI’s in other galaxies should be detectable with today’s mid-infrared (MIR) surveys, such as that just conducted by the WISE satellite.” (2)
However, the upside to focusing on large, established civilizations is the fact that it should limit the number of false positives. The theory is that the heat emitted by a large civilization should set that civilization apart from the natural background heat of the universe.
Also, it should help researchers differentiate that civilization from other naturally occurring forms of heat. “We discuss the likely sources of false positives, how dust can and will contaminate our search, and prospects for distinguishing dust from alien waste heat.” (3)
However, the big question on everyone’s mind is how accurate and how likely is the survey to actually find something? The answer is that it may already have.
Are There Aliens Out There?
The researchers have found a number of galaxies that appear to emit more than the baseline of heat for the natural universe, which would imply some sort of extraterrestrial activity.
However, it is also not unusual for the increased heat emissions to be the result of natural processes. When asked by the OuterPlaces if the researchers found anything, Wright’s reply was:
“If by ‘found them’ you mean that WISE detected the waste heat from them, then yes, that’s right – if these sorts of energy-hungry civilizations exist, WISE should have detected them.” (1)
Yet, he goes on to state that actually determining if that heat is from an advanced alien civilization will be a much more arduous task.