Our civilization is probably not the only developed
"From a fundamental point of view, the question is:? Has it anything like that before," says Adam Frank, professor of physics and astronomy at the University of Rochester. "And it is highly likely that our time and place - is not the only one of those where there were advanced civilizations."
"The question is whether there are advanced civilizations elsewhere in the universe, always intertwined with three unknowns in the equation of Drake," Frank says. "We have long know approximately how many stars there are. We do not know how many of these stars have planets that could support life, it may often appear life and lead to the emergence of intelligent beings, and how long a civilization can survive before disappearing. "
"We do not even know if a high-tech civilization can survive more than a few centuries."
"Our findings suggest that our biological and cultural evolution are not unique, and probably happened many times before. Other examples may include a variety of energy-intensive civilizations that faced with the crisis on his planet with the development. This means that we can begin to investigate the problem, using simulation to understand what leads to long-lived civilizations and what is not. "
A new study shows that the recent discovery of exoplanets in conjunction with an active exploration of this question allows to assign virtually empirical accuracy of the existence of technological civilizations. In short - they must have existed. And if only the odds of developing the development of life are incredibly low, the human race will not be exact the first technology or advanced civilization. In 2016, in a paper published in the of Astrobiology, scientists have shown for the first time, which means "pessimism" and "optimism" in the estimates of the likelihood of extraterrestrial life.
"With NASA's Kepler satellite and other search, we now know that about every fifth star has planets in a" potentially habitable zone "where temperatures can sustain life as we know it. Thus, one of the three large uncertainties acquired constraints ".
With the new results Frank and Woodruff Sullivan (University of Washington), scientists can arm themselves with all that they know about the planets climate and to start modeling interactions energy-intensive to their home world, suggesting that a large sample of cases already existed in space .
Frank says that the third big question Drake - how civilization can survive for a long time - do not answer at all. "The fact that people were not primitive technology about ten thousand years, tells us nothing about how many others can live our society," he explains.
In 1961, astrophysicist Frank Drake introduced an equation for estimating the number of advanced civilizations that might exist in the Milky Way. It looks like this: N = R * (fp) (ne) (fl) (fi) (fc) L, decoding of each variable below. Based on simple statistics, it is easy to calculate that somewhere there may be thousands, even millions of extraterrestrial civilizations:
- R * - the rate of star formation in our galaxy.
- fp - the percentage of stars that have planets.
- ne - number of Earth-like planets around each star has a planet.
- fl - the percentage of Earth-like planets that have developed life.
- fi - the percentage of life-bearing planets on which intelligent life has evolved.
- fc - the percentage of intelligent species that have come before the creation of technologies that can detect external forces of civilization like ours. For example, signals.
- L - the average number of years required an advanced civilization to detect detectable signals.
Drake Equation proved a solid basis for research and space technology have allowed scientists to identify several variables. But we are left wondering what could be the variable of L, the estimated service life of other advanced civilizations.
Using their approach to the analysis of exoplanets in the universe of data, Frank, and Sullivan sewed to the conclusion that human civilization will be unique in space only if civilization will develop on the relevant planet less often than once in 10 billion trillion (10 22)
"One of the ten billion trillion - is extremely small," Frank says. "As for me, this means that other reasonable, technologically advanced form of certain developed before us. Even if the chance of intelligent life estimated at one in a trillion, that would mean that over cosmic history intelligent life appeared at least ten billion times. "