Life from extraterrestrial sources

Extraterrestrial Assay Candidates : No Transmissions from Intrinsically Steady Sources

This paper reports new, more sensitive observations of nine of the eleven extrastatis-tical signals in the Megachannel Extraterrestrial Assay (META). These extrastatistical signals had all of the expected characteristics of a transmission from an extraterrestrial transmitter, except that they did not repeat. Cordes, Lazio, & Sagan showed that this lack of repeatability could be explained by the...

A Non-specialist's Comment on Extraterrestrial Life

The affirmative statement of the existence of extraterrestrial life is tentatively raised to the status of a principle. Accordingly, Fermi's question is answered and the anthropic principle is shown to be fal-sifiable. The timescale for the development of life on Earth and the age of the universe are the fundamental quantities upon which the arguments are framed.

Concepts for Detection of Extraterrestrial Life

Microlensing and the Search for Extraterrestrial Life

Are microlensing searches likely to discover planets that harbor life? Given our present state of knowledge, this is a difficult question to answer. We therefore begin by asking a more narrowly focused question: are conditions on planets discovered via microlensing likely to be similar to those we experience on Earth? In this paper I link the microlensing observations to the well-known “Goldilo...

Extremophiles and the search for extraterrestrial life.

Extremophiles thrive in ice, boiling water, acid, the water core of nuclear reactors, salt crystals, and toxic waste and in a range of other extreme habitats that were previously thought to be inhospitable for life. Extremophiles include representatives of all three domains (Bacteria, Archaea, and Eucarya); however, the majority are microorganisms, and a high proportion of these are Archaea. Kn...