Radio searches for large-scale extraterrestrial organisms

摘要

A variety of means can be employed to search for extraterrestrial life. Large-scale extraterrestrials are reasonably expected to have developed intelligence (since intelligence is selectively advantageous) and technology (since technology also provides advantages). In the expectation/hope that more advanced extraterrestrials will be sending an announcement signal to help us make contact and share in our galactic heritage, more than 30 radio searches have been carried out over the last 40 years. Current searches are up to 4 orders of magnitude more sensitive and cover up to 108 more bandpass than the original searches. An overview of the rationale behind these searches and the current status of this work is provided.