A survey of galaxies with the WISE space telescope has turned up about 50 of these with excess mid-infrared radiation, it has just been announced. This is just the sort of radiation that might be emitted by extraterrestrial civilizations that were harnessing the entire energy output of their stars, via dyson spheres.

The challenge now is to ascertain if this is the case here, or if a natural explanation, such as the interception of stellar light by an unusually large amount of interstellar dust is responsible.
Link to article on this, below:
http://www.dailymail.co.uk/sciencetech/article-3042085/Could-galaxies-hiding-advanced-alien-life-infrared-emissions-suggest-beings-using-stars-energy-study-claims.html

More reasons for scientists to use new technologies to explore Arp 220 in high resolution detail. Light sail projects are an excellent opportunity for crowd sourcing funds for this project beyond our expectations.

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