Is there anybody out there? Maybe. Maybe not. Though there are more reason to believe that we aren’t alone, nobody yet contacted us. Scientists are trying to contact them. Apart from UFOs stories we kept hearing and which scientists kept rejecting, something happened in 1977 which scientists are still baffled about. Amidst the persistent noises of this vast universe, scientists were able to hear a ‘song’ which lasted some 72 seconds. The ‘song’ was too good to be an accident. Much to the disappointment of scientists, the song was never to be heard again. 37 years have passed since then but those 72 seconds never came again. Check this link for wonderful presentation by Brian Cox. If you think the song we listened to was some kind of accident, we, too, have sent our own messages to contact aliens. The earliest message was put on Pioneer 10 spacecraft in the form of a plaque. (See image below.)
It seems, though, our love (or hate?) for those alien civilization is not a recent development. Couple of months back, there was this news of 10,000 years old rock painting being found in India depicting aliens and UFOs. What were those cavemen thinking when they painted those aliens? Or were they lucky enough to have seen them? In case you want to dismiss this, what to make of that 20,000 years old paintings found in France? In any case, aliens, in our imagination, has always been there all around the world. Unlike ghosts, possible existence of aliens is much more plausible.
The immense vastness of universe, in a sense, ensures there might be alien life somewhere but it also poses difficulty in finding it. There should be, and possible are, millions of planets in this universe which are ‘earth like’ and it is not unreasonable to think that there should be some planets which are inhabited by some sorts of living creatures. The size of universe is unfathomable and the farthest point that is visible from earth is almost 46 billion light years away! What does that mean? That means if you are traveling at a speed of, let us say, 1000 kilometers per second (yes, per second), it will take 13,800 billion years to reach that point. Let me emphasize again I am talking about the farthest point that is visible from earth rather than the absolute farthest point. Nothing existed that long. Nothing would probably exist that long. Our universe is merely 13.8 billion years old. The star you wished upon last night probably has died millions of years ago. Kind of disheartening, no?
Not exactly. In 2012, scientists reported to have found glycolaldehyde, a type of sugar, in an adolescent star. This was very important news. You should check the ALMA Observatory website. First, even before this discovery, it is known that RNA molecules were the earliest form of organic molecules responsible for life and one of the three ingredients (DNA, RNA and proteins) of all form of lives. The sugar mentioned above is the basic ingredient for RNA. Second, these sugar molecules happen to be there at the right time and at the right place. That new born star will pass on these sugar molecules to the planets which are yet to be formed. In all probabilities, we won’t live long enough to see what happens next there. The star we talked about is ‘merely’ 400 light years away. Perhaps in some other corner of universe, the sugar molecules have already played their roles in RNA molecules formation. Our distant past when life just began is being repeated somewhere. Possibly. In fact, other organic molecules such as glycine (an amino acid) have been found on a comet. This and other such instances show that basic ingredients of life are in abundance in universe which may give rise to rise to life in presence of other supporting environmental factors. Both practically and theoretically, there are more reasons to believe that there is someone out there.
But where are they? There is this interesting and analytical discussion around the Fermi Paradox concerning with probability of extraterrestrial life. Even if alien life exists, should we contact them? Some say yes, some say no. Yes, because it will overwhelmingly enhance our knowledge and understanding of myriads of topics such as biology, evolution, society, religion and science. May be they have discovered the Grand Unified Theory of everything. May be they have solved Riemann Hypothesis. What about their views on God? Are there males and females? Do their lives depend of sun and water? Are DNA and proteins building blocks of their biology? And so on. Or may be we shouldn’t contact them at all. What if they are technologically advance and yet a predatory race hunting for resources? Stephen Hawking is quite pessimistic about it. He warned any contact with alien life may cause trouble to us. In any case, our search for extraterrestrial life wouldn’t stop.