Humanity has come to terms with being alone in the wilderness of the universe with every single speculation on spotting intelligent extra terrestrial life yielding no result. Aliens thus exist only in our imagination fueled by colorful fictitious characters.
Term 'extra-terrestrial life' refers to a hypothetical range of life starting from simple bacteria-like organisms to sapient beings which are far more advanced than humans. According to scientific research, celestial bodies with potential capacity to sustain life include Mars, Venus, Jupiter, Moons of Jupiter - Ganymede, Callisto, and Europa, and Moons of Saturn-Titan, and Enceladus.
The failure of the SETI program (Search for extraterrestrial intelligence- collective name for a number of activities people undertake to search for intelligent extraterrestrial life) to announce an alien radio signal from outer space has partially dimmed hopes of humans' encounter with life forms outside earth.
Is there Hope for SETI?
SETI estimates the number of advanced civilizations that might exist among galaxies, by means of "Drake Equation" devised by Frank Drake, Emeritus Professor of Astronomy and Astrophysics at the University of California, Santa Cruz. Being intensely speculative, the equation arrives at tentative solutions by multiplying values like 'the number of civilizations in The Milky Way Galaxy whose electromagnetic emissions are detectable,' 'the rate of formation of stars suitable for the development of intelligent life,' 'the fraction of those stars with planetary systems,' 'the number of planets, per solar system, with an environment suitable for life,' and so on. (More on Drake Equation).
The major ambiguity about Drake Equation is that it assumes and completely relies on a speculative factor: According to the equation, the probability of life arising on suitably habitable planets (ones with water, rocky surfaces and atmospheres) is almost always taken to be 100 percent, says Space.com.
Probability of Abiogenesis (method by which life on Earth arose):
David S. Spiegel of Dept. of Astrophysical Sciences, Princeton University, and Edwin L. Turner, of Institute for the Physics and Mathematics of the Universe, The University of Tokyo in their research paper titled "Life might be rare despite its early emergence on Earth: a Bayesian analysis of the probability of abiogenesis" argue that the probability factor of abiogenesis varies from planet to planet, and a assigning a constant value for probability will only lead to biased solutions.
Humans Have a Lot to Tell Aliens; Mostly About our Miserable Lives!
SETI has a dedicated section in their official Web site where people can write the message they would like to convey as and when an intelligent alien is detected. The forum is flooded with thousands of messages, some of which reveal a lot about human presumptions about aliens.
A large chunk of messages voice the bad state of affairs on Earth: "We got your message. Unfortunately our leaders are lying to us, and we can't stop them. We have lost our universal consciousnesses, and we don't know what we are. Our energy has been drained from the system that puts dollar signs in our eyes so we are weak to search for you. The contempt has won over the battle with questioning. We know we might not be worth saving."
Some warn aliens about taxes, pollution, racism and even job cuts. "Don't come to Earth please; air is too polluted and they will tax you for everything. Winter is too cold in the continent and job wise forget it. Plus they predicted that earth will die in 2012. Humans are racist too and you wouldn't be able to settle down in this planet."
Most of the messages assume that aliens would be far more tech savvy than humans. "Our offerings in science and technology are probably quite limited because we are new to this activity. However, in the areas of art, philosophies, and law we have quite a large set of material that could be useful and interesting for other civilized worlds. We will periodically transmit data packets containing information to speed up our interactions somewhat."
Some others want to know how it works on alien planet. "What kind of social, economic and political system do you have? Have you eradicated poverty and social inequality? Are your genders equal? Do you have wars or is there peace on your planet?"
Some others have written humorous messages like "Welcome to our home for dinner," "If you're traveling at the speed of light and you turn on your headlights, do they do anything?"
Some have used the forum to voice prejudices with funny messages like, "If you land in China, dial 911 immediately!" and "Welcome to Hollywood, please sign the contract."
"We are made of matter. Matter and anti-matter annihilates. Therefore, please check your composition first before making contact with us."
However, there is also a section which remains unconvinced about SETI's message board exercise. They say it is fallacious to assume that aliens would speak English!
"The problem isn't if or what to say, it's How. They don't speak our languages. We can't send a picture of an apple and say "apple". They don't have apples! The only comparative objects we have are atoms, molecules, celestial objects, etc. They might see in infrared or even gamma rays. They might hear at frequencies tens of times higher or lower than us. Maybe they use telepathy? How can we decide what to say, if we don't even know how to say it in the first place?"