Do you think its possible to find aliens in your lifetime? The chances that an extraterrestrial civilization would actually come to the Earth are slim. However, if they did the best way to find extraterrestrial life is not by space exploration, but by electronic signals. Signals can carry words, numbers, and pictures cheaply and at the speed of light. The amount of time and energy required for the travel would be enormous.
The amount of energy required to accelerate a spacecraft weighing several thousand tons to a speed even a moderate fraction of the speed of light would be billions of times more than the energy needed to send out a radio beacon (Big Ear Radio Observatory 4). Therefore, it’s more likely that they would communicate instead, thats if there are intelligent beings out there who want to communicate with us (Life Beyond Earth). Today we have the means to broadcast messages to the planets and stars but is anyone out there listening?
If we are leaking radio messages into space, the inhabitants of other planets, if they exist, might be doing the same thing. Large radio telescopes on Earth could detect such radio leaks from civilizations in nearby star systems, as well as stronger signals dispatched from planets thousands of light years away (Boyle 2). The idea of searching for extraterrestrial life has been dreamed of through the ages, but the methodology began in 1959 when two physicists from Cornell stated that microwave radio waves could be used for interstellar communication (2).
The first signal was sent from the 1,000-foot Observatory in Puerto Rico on Nov. 16, 1974, during a ceremony celebrating an upgrade of the radio telescope. The signal was sent out toward M13, a globular cluster comprising some 300,000 stars about 21,000 light years from Earth. Astronomers figured the focused 50,000-watt signal would be strong enough to be picked up by an antenna somewhere in that cluster, but ironically, the normal rotation of the galaxy means that M13 will have moved out of the way by the time the signal gets that far (Boyle 3).
Civilizations might communicate in one of two ways. The first way is by sending signals unintentionally. We do this all the time ourselves. For over fifty years now, our first television and radio signals have been radiating out into space like a giant shock wave, or like waves radiating out from a pebble dropped into a pond. Another intelligent civilization could intercept them and wonder what they say. Imagine an alien race picking up one of our television signals, decoding it, and then sending what they believe to be an intelligent reply (Big Ear Radio Observatory 5).
At the time, some observers wondered whether it was wise to send out such a signal. Some thought it was egotistical to transmit a message to aliens without the backing of a worldwide authority like the United Nations, and some worried that the signal might even attract unwelcome extraterrestrial interest. Other astronomers point out that Earth has been leaking radio signals into space for more than fifty years and that at least some of those transmissions are strong enough to alert nearby star systems of our presence (6).
Radio astronomers recently showed off a network of model satellite dishes that will serve as the proving ground for a new generation of radio telescopes. They called this project 1 HT. They said such arrays combined together by computer software would boost their ability to communicate with interplanetary probes, study distant planets and search for alien signals (7). This prototype launches the next generation of SETI research in a bold way, Tarter, the institutes director of SETI research, said in a written statement.
There is also tremendous potential for other radio astronomy. The 1HT is a fundamentally new way to build radio telescopes, and its not an overstatement to say that the world astronomy community is paying very close attention to this project (Boyle 4). Tarter emphasized the wider applications of the 1HT and the Square Kilometer Array. She said a telescope array with an area equivalent to a square kilometer couldidentify Jupiter-size planets beyond our solar system; as far away as thirty light-years from Earth.
With this kind of size of telescope its possible to map the winds and jets created during star formation, and analyze the chemistry of the dusty disks that serve as the birthplaces of stars and planets. Serve as the model for a next-generation Deep Space Network that would communicate with robotic explorers. Produce radar images of near-Earth asteroids that are ten times better than currently possible and finallyexpand the SETI search to up to a million star systems. The Square Kilometer Array would be unlike any existing radio telescope.
An alien message would also most likely be what we call a narrowband signal. This means a signal at a very precise frequency. Radio stations are examples of narrowband signals. Between radio stations, you hear a hissing sound. This is a broadband noise. The stars (and other celestial objects) also put out broadband noise. An intelligent, communicating civilization would probably use a narrowband signal rather than a broadband one for a beacon, since they wouldn’t want their message to be mistaken for regular, ordinary star noise (Billinham 4).
Perhaps there are civilizations that are very much more advanced than we are. Just imagine the wealth of knowledge that would be at our fingertips if we were to discover such a signal and decipher it (Life Beyond Earth). Perhaps it would teach us how to build a space ship that travels close to the speed of light. Or maybe it would tell us how to solve our planetary ecological crisis. It might be able to solve our global political problems? The benefits of such a discovery could be beyond our wildest dreams!