For as long as humans have walked the Earth, we’ve wondered whether we are alone in the universe. In the last century, the steady march of technology has finally given us the tools to begin searching for the answer to this question. Unfortunately, in an ironic twist, technology may also be rendering these tools useless.
Searching In The Dark:
The process of searching for signs of extraterrestrial life is not an easy one. Because of the vastness of space, it’s virtually impossible to visually detect life elsewhere in the universe. Instead, scientists must rely on alternative means to detect potential signs of intelligent life. Spearheaded by a collection of scientists working for the Search for Extraterrestrial Intelligence, colloquially referred to as SETI, the primary search tool is scientific analysis of electromagnetic radiation and other signals from space.
Electromagnetic radiation is of interest to scientists because it is assumed to be the most likely method of communication used by extraterrestrial life. This assumption stems from the fact that, until recently, the majority of our communications and entertainment technology, including radio and television, involved the broadcasting of a strong analog signal. When such a signal is broadcast, a portion of its electromagnetic radiation is lost to space, where it continues to propagate in all directions relatively undisturbed. Because this shell of radiation travels at the speed of light, our signals now expand many light years from the Earth.
The Digital Revolution:
Scientists have always assumed that this same process would take place on any other planet bearing intelligent life, allowing us to eventually detect the resulting radiation shell of these planets. This assumption, however, has been challenged in recent years by our transition to digital signals. Rather than traditional analog signals, many radio, television and communications signals are now broadcast in digital form. While this has provided many advantages, there are significant problems in the search for life.
The most immediate problem with a switch to digital is that, assuming life elsewhere has some similarity to our own, other intelligent beings will likely have already transitioned to digital signals. This would fundamentally change the way that SETI and other organizations search for life, render many past efforts irrelevant, and make it more difficult for extraterrestrial civilizations to detect us as well. Our familiar digital DISH Network signal would appear as nothing more than noise to a curious civilization, while their radio chatter would likely be indistinguishable from random background noise.
Further complicating the issue is the fact that digital signals require significantly less energy. Rather than the million watts or more required by many analog transmitters, digital transmitters of the type used by DISH Network and other television broadcasting companies often use as little as 20 watts. This releases much less energy to space, continually reducing the Earth’s future electromagnetic footprint. Additionally, the energy that is used is precisely aimed at orbiting satellites and reflected back to Earth, reducing the leaked energy even further
Although scanning the skies for strong electromagnetic signals may no longer be a viable search option, several alternatives may be available in the future. The most feasible option in the near future is an exceptionally powerful pulsed laser, which could produce a momentary flash more luminous than the Sun. This could effectively be used as a signaling beacon, and SETI has now begun looking for such signals from space.
In the distant future, the Sun itself may also be used to assist in the search for life. Using a phenomenon called gravitational lensing, in which light and energy are bent around objects with intense gravity, the Sun could be utilized as an ultra-powerful lens, achieving one million-fold magnifications at a central focal point. This focal point, however, lies well beyond the solar system and is inaccessible with current technology.
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Tech writer EJ Parfitt has been writing for a short time now and has already picked up steam with several tech websites , Dish and local news sites . During his free time , you’re sure to catch him competing in local chess tournaments in downtown Fort Lauderdale FL .