"Long before it's in the papers"
January 27, 2015


Astronomers hope to find alien civilizations through heat

May 31, 2013
Courtesy of Astronomy Magazine
and World Science staff

Sci­en­tists have pro­posed a new way to look for al­ien civ­il­iz­a­tions: watch­ing plan­ets to check for ab­nor­mal amounts of heat be­ing giv­en off.

Most at­tempts to find al­ien civ­il­iz­a­tions have re­lied on look­ing for ra­di­o sig­nals. In­stead, as­tron­o­mer Jeff R. Kuhn of the Uni­vers­ity of Ha­waii and col­leagues pro­pose a gi­ant tel­e­scope that could de­tect in­fra­red, or heat, radia­t­ion di­rectly from an al­ien plan­et.

“The en­er­gy foot­print of life and civ­il­iz­a­tion ap­pears as in­fra­red heat radia­t­ion,” said Kuhn, the pro­jec­t’s lead sci­ent­ist. “A con­ven­ient way to de­scribe the strength of this sig­nal is in terms of to­tal stel­lar pow­er that is in­ci­dent on the host plan­et.” 

The idea arises from the fact that a civ­il­iz­a­tion pro­duces pow­er that adds to the heat on a plan­et, be­yond the heat re­ceived from its host star. A large enough tel­e­scope, ide­alized for in­fra­red de­tection, could sur­vey plan­ets or­bit­ing stars with­in 60 light-years of the Sun to see wheth­er or not they host civ­il­iz­a­tions, Kuhn and col­leagues ar­gue. A light-year is the dis­tance light trav­els in a year.

The in­terna­t­ional team is seek­ing fund­ing to build a spe­cial 77-meter tel­e­scope, dubbed “Colos­sus,” for the pur­pose. The sci­ent­ists de­scribe the pro­pos­al in the June is­sue of As­tron­o­my mag­a­zine.

Colos­sus’s field of view would be op­ti­mized for star-like sources. It’s en­vi­sioned as the world’s best high-resolution in­fra­red tel­e­scope, ex­cel­ling at the study of stel­lar sur­faces, black holes, quasars, and ob­jects that ap­pear smaller than 1/3,600 of a de­gree on the sky.

A com­pa­ny called In­no­va­tive Op­tics Ltd. is be­hind the tech­nolo­gies that make Colossus-style tel­e­scopes pos­si­ble, the as­tron­o­mers said. The com­pa­ny op­er­ates its re­search and de­vel­op­ment at the Uni­vers­ity of Ha­wai­i’s In­sti­tute for As­tron­o­my in Maui.

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Scientists have proposed a new way to look for alien civilizations: watching planets to check for abnormal amounts of heat being given off. Most attempts to find alien civilizations have relied on looking for radio signals. Instead, astronomer Jeff R. Kuhn of the University of Hawaii and colleagues propose a giant telescope that could detect infrared, or heat, radiation directly from an alien planet. “The energy footprint of life and civilization appears as infrared heat radiation,” said Kuhn, the project’s lead scientist. “A convenient way to describe the strength of this signal is in terms of total stellar power that is incident on the host planet.” The idea arises from the fact that a civilization produces power that adds to the heat on a planet, beyond the heat received from its host star. A large enough telescope, idealized for infrared detection, could survey planets orbiting stars within 60 light-years of the Sun to see whether or not they host civilizations, Kuhn and colleagues argue. A light-year is the distance light travels in a year. The international team is seeking funding to build a special 77-meter telescope, dubbed “Colossus,” for the purpose. The scientists describe the proposal in the June issue of Astronomy magazine. Colossus’s field of view would be optimized for star-like sources. It’s envisioned as the world’s best high-resolution infrared telescope, exceling at the study of stellar surfaces, black holes, quasars, and objects that appear smaller than 1/3600 of a degree on the sky. A company called Innovative Optics Ltd. is behind the technologies that make Colossus-style telescopes possible, the astronomers said. The company operates its research and development at the University of Hawaii’s Institute for Astronomy in Maui.