December 5, 2011 23:50
Somewhere in space, the 36 light-years away in the constellation Hercules, series of 1679 of frequency-modulated signals, stretching up to 50 million km, carries a message from Earth.
Broadcast from the Arecibo radio telescope in Puerto Rico took place in 1974, American astronomer Carl Sagan enthusiast and founder of SETI, Frank Drake. They hoped that any intelligent alien can understand that 1679 — is the product of prime numbers 23 and 73. If you organize all transmitted ones and zeros in a grid of 23 columns and 73 rows, you get a number of simple, ASCII-like figures, including a double helix and a rough image of the person. In addition, an extraterrestrial civilization might notice that these signals at 10 million times stronger than the background noise of the sun.
Transmission system was designed, located 25 thousand light-years from Earth. Alas, the time of arrival, it will take away from the destination point signals. The chances of two public whatsoever civilizations such communications are very small even for a different reason. The likelihood that someone is at the right time in the right place, is practically zero. Need a repeating signal. It is necessary to build a lighthouse that can emit millions of years.
But first we need to understand, is it worth writing to neighbors. Once in 1999 and 2003, the Russian scientist Alexander Zaitsev has sent several messages using the Ukrainian radio transmitters, scientists have been saying it is not good to do things without asking. Many people think that to find myself — not a good idea, because no one knows what could be the intention of the aliens. Perhaps there will be the same as in America: a new white race will drive us to the reservation or destroy. With the new technology the small group of Cortez conquered the Aztec empire strong for two years, although the level of scientific and technical progress of Europe than America for a thousand years, in the stellar scale ridiculous.
However, while there is nothing to fear. Transfer "upstart" Zaitsev and his colleagues were sporadic.
Of course, there is no need to take risks, but you can try to preserve the heritage of the Earth by interplanetary … alarm. Imagine a transmitter, which is silent, until the operator from time to time certain button presses. Once the system notices that it has been, say, 500 years, the button is at rest, it begins to signal the alien archaeologists and does it for millions of years.
But now, apparently, we do not have technologies to build such a reliable and energy-efficient car. Some even believe that to create something that did not violate any laws of physics, in principle, impossible. Nevertheless, the work has already begun.
For example, there is a lively discussion of the project in the blog Centauri Dreams, and twin brothers James and Physics Gregory Benford (the latter also does the writing NF) published a paper in the journal Astrobiology, which tried to consider the possibility of building such a beacon from an economic point of view. Conclusions about such. In the near future is not expected no technology capable of transmitting powerful signals every minute for several epochs. But you can broadcast messages to selected star system, repeating them every few months. Theoretically it would save enough energy to run for millions of years.
Benford's offer to place a beacon in solar orbit, about halfway to the earth: there is enough energy to power solar cells and at the same time not so much heat, so the equipment does not overheat. The system can be supplemented with back-up generator power as a result of radioactive decay (as in "Voyager 2").
Yes, the station will be the target of micrometeorites and man-made debris. But this problem can be solved by installing special robotic cleaners and repairers (in the future and always will be). Moreover, the device will be quite compact, so the chances of a collision with a large object is very small.
Benford believe that all the necessary technologies will be with us in a few decades.
Meanwhile, do not forget about the "Ozimandii syndrome" (in the famous poem Percy Bysshe Shelley): we are building a monument rather than care for the preservation of civilization. According to many, the current state of geopolitics can dream of such projects. We would have to survive first, and then talk about the machines that can operate for millions of years.