It’s very unlikely that we are alone in this Universe. There may be aliens not right next door, but may be within a thousand light years or so. They may not be little green men. They may not arrive in a vast spaceship. But according to new studies there could be as many as 36 intelligent civilisations in our galaxy today capable of communicating with each other and with us.
S. E. T. I is an acronym for Search for Extra Terrestrial Intelligence. It is an idea where we assume that if there is life, and there are human beings elsewhere in space and they are as wise and as intelligent as we are, then technologically, they might have also reached a level at least equal to ours. Then as we want to explore the possibility of life in the outer space, so might be they. These thoughts have already entered into the realm of experimental science. In 1896, Nikola Tesla had suggested that an extreme version of his wireless electrical transmission system could be used to contact beings on Mars. Monitoring electromagnetic radiation for signs of transmissions from civilizations on other planets became the focal point of research in this direction. Scientific investigation began shortly after the advent of radio in the early 1900s, and sustained efforts are being carried out since 1980s. The primary indicator to determine whether a signal might be extraterrestrial is to see if it remains stable in the sky. So if we see a signal at a spot in the sky, and then come back and look at the same spot a month later and it’s still there, then we may say we have something new. However, nearby signals, from a radar system, for example, typically are seen at many positions on the sky, so if we think we have got something new, we have got to cross-check. Researchers say that they can only locate intelligent and technically advanced civilizations that use radio waves as a form of communication. In 2015, Stephen Hawking together with Russian billionaire Yuri Milner announced a well-funded project in this direction, known as Breakthrough Listen. Astronomers involved in this project have been searching for signals from alien civilisations and they had detected 15 powerful, repeated radio pulses coming from a dwarf galaxy 3 billion light years away from Earth. These fast radio bursts are mysterious signals, and their source is unknown. Some researchers are of the opinion that they could be emanating from black holes or rotating neutron stars with extremely strong magnetic fields. A more speculative possibility, however, is that they are beacons from extraterrestrial spacecraft. In 1961 the astronomer Frank Drake proposed an equation which sets out seven factors to know the number of intelligent civilisations out there. These factors include the average number of stars that get formed each year in the galaxy and the timespan over which a civilisation would be expected to be sending out detectable signals. As for instance, it would need us to survive at least another 6,120 years for two-way communication with the closest alien civilization, thought to be 17,000 light years away from us as per the calculations. Currently, there are many secret space programs going on to examine the ancient history and testimonies indicating an extraterrestrial presence on Earth. There are more than a dozen evidences, controversial though, attesting the alien life in the outer space. Tests performed on the soil samples of Mars by NASA’s Viking landers hinted at chemical evidence of life. Similarly, in August 1977, an Ohio State University radio telescope detected an unusual pulse of radiation from somewhere near the constellation Sagittarius. In 2004, a mysterious radio signal was received by the SETI project on three occasions – from the same region of space. Fiction and movies are also making their contribution to popularise the idea of Alien Life. The 2003 block-buster of Indian Cinema “Koi Mil Gaya” received the National Film Award for Best Film on Other Social Issues. The hero, Rohit, inadvertently summons the aliens by means of a computer built by his scientist father from which he sends variations of the syllable om into space, attracting extraterrestrial life. Some other films with extraterrestrial life themes, motifs, characters etc. include Deceit (1989), Dark City (1998), The Day the Earth Stood Still (2008) and so on. The concept of cosmic pluralism is based on the assumption that there are many inhabited worlds beyond the human sphere which predate modernity and even the development of the heliocentric model. It is also common across worldwide mythologies. The 2nd century writer of satires, Lucian, in his work “True History” claims to have visited the moon when his ship was sent up by a fountain, which was populated by the people from earth to fight with the people of the Sun over colonisation of the Morning Star. Other such works include the 10th-century Japanese narrative, The Tale of the Bamboo Cutter, and the medieval Arabic one such as The Adventures of Bulukiya (from the One Thousand and One Nights). Science fiction about aliens is both in terms of metaphors and real possibilities. Thus, the subject of aliens will likely remain a central theme in science fiction until one day we may actually encounter them.
Dr. Qudsia Gani is Assistant Professor, Department of Physics, Govt. College for Women