Monday, April 13, 2015

E.T. Leave Home

The prospect of extraterrestrial life intrigues us, as the idea that we are the only living organisms in the universe seems improbable, especially given the large number of planets in the universe. However, it is troubling that we have yet to come in contact with any extraterrestrial biosignatures, which could mean a multitude of things regarding both the existence of extraterrestrials and, if they exist, the level of their intelligence.

Enrico Fermi asked the question “Where is everybody,” referring to our lack of contact with extraterrestrial life. Fermi’s paradox argues that there is a contradiction between the high probability that extraterrestrial life exists and our lack of contact with it. This is especially true in that Earth and the Sun are relatively young in comparison to other planets and stars which populate the galaxy. Given the plausible timescales of colonization, we should be surrounded by colonized planets and moons. This leads some to believe that intelligent extraterrestrial life either does not exist or wishes to remain unknown to us.

This lack of contact with extraterrestrial life could lead us to believe that extraterrestrial life, if it exists, may not be advanced. Instead of thinking about a stereotypical alien with futuristic technologies, such as a Martian piloting a U.F.O, that alien could very well be a microscopic organism such as a bacterium that thrives in inhospitable climates, like Earth’s extremophiles do. The existence of extremophiles on Earth has made us rethink where life could exist elsewhere in the universe. Planets very similar to Earth’s habitability are no longer the only places for where life could exist. Scientists have recently proposed that there could be methane-based, oxygen-free extraterrestrial life, further showing how different extraterrestrial life may be compared to Earth’s.

Research in the field of astrobiology is still young and there is still much debate on what materials are required for life. The main hindrance is that we can only study life on Earth, which shouldn’t be extrapolated across the entire universe, as life may exist in forms that we have yet to imagine. The first extremophiles were only discovered fairly recently, in the 1970s, and perhaps there are more species yet to be found. Extraterrestrial life may exist in ways we wouldn’t think are possible.

Also, the ways that we search for extraterrestrial life are influenced by the technologies that we have, but perhaps aliens use technologies that we cannot even envision. Until we broaden our methods of searching, it may continue to be unfruitful. For instance, NASA's James Webb Space Telescope, or JWST, will directly observe the atmospheres of nearby "super-Earth" alien planets, searching for the chemical signatures of extraterrestrial life. As our technology continues to develop, we will be able to detect biosignatures of exoplanets remotely and eventually we will be able to visit those exoplanets to confirm the existence of extraterrestrial life. We shouldn’t get disheartened now, since it our technology is still very lacking and the prospect of extraterrestrial life is very high. If it exists, we will be able to find it eventually given sufficient resources and time.

Sources: