Where to find aliens

But law enforcement officials took the idea very, very seriously. The water flowing from a medieval fountain in the Italian village of Fontecchio bubbles with extraterrestrial effervescence.

The creepy alien abduction horror game "They Are Here: Alien Abduction Horror" is coming in and there's a free-to-play demo available now. Researchers show how intelligent aliens might draw nearly-limitless power from a black hole using a Dyson sphere.

Two aircrafts flying over Canada reported a "bright green UFO" that disappeared into the clouds on July The search for extraterrestrial technology is "daring to look through new telescopes. People have described extraterrestrial encounters that take place in a dreamlike state, and experiments suggest that such experiences may be lucid dreams.

Robots may have to dig relatively deep on Jupiter's ocean moon Europa to have a shot of finding signs of alien life, a new study suggests.

The methane wafting from Enceladus may be a sign that life teems in the Saturn moon's subsurface sea, a new study reports. A new survey reveals that most Americans believe in intelligent extraterrestrial life and do not feel threatened by the appearance of UFOs.

A couple may even have atmospheres. And still other places that seem to be too exotic for life continue to surprise us. They could study things up close, maybe fly into the atmosphere or land on the surface, and perhaps one day even bring back samples that could reveal whether these planets and moons are home to materials or fossils that are evidence of life—or perhaps life itself.

Triton is the largest moon of Neptune, and one of the most exotic worlds in the solar system. Its surface is mostly frozen nitrogen, and its crust is made of water ice, and it has an icy mantle. Yes, this is a cold, cold world.

But in spite of that, it seems to get some heat generated by tidal forces gravitational friction between Triton and Neptune , and that could help warm up the waters and give rise to life through any organics that might exist on the moon. But actually finding life on Triton seems like a very distant possibility. The only mission to ever visit the world was Voyager 2 in The window for such a mission opens up only every 13 years. The best opportunity to visit Triton would be the proposed Trident mission which seems unlikely to get launched after NASA just greenlighted two new missions to Venus later this decade.

And lastly, the horrendous cold tempers hopes that life could stay unfrozen for long enough to make a home for itself. The largest asteroid and smallest dwarf planet in the solar system could be home to liquid water, sitting deep underground. Dawn even found evidence of organic compounds on Ceres that could act as raw materials for life.

But Ceres ranks second-to-last on our list because its habitability has too many questions attached. The evidence of subsurface water and the organic materials is still very new. Even if those things are there, it would need some source of heat and energy that could actually help encourage that water and organic material to react in such a way that it leads to life.

And even if that occurred, finding that life means we have to drill at least two-dozen miles into the ground to access that water and study it. Lastly, Ceres is tiny—more than 13 times smaller than Earth. But nothing is going up soon. Boasting over active volcanoes, Io is the most geologically active world in the solar system.

There might even be a subsurface ocean on Io, but it would be made of magma, not water. Life on Io is very unlikely. But all that heat is a bit of an encouraging sign. But like Trident, IVO was vying for the same mission spots that were snatched by two upcoming Venus missions.

It also retains a thin atmosphere of hydrogen, carbon dioxide, and oxygen, which is more diverse and Earth-like than most of the other solar system moons that could be habitable. The largest moon to orbit Jupiter, and simply the largest moon in the solar system, is covered up in an icy shell. Naturally, all that water has scientists hopeful that some kind of life could exist on the moon. One such system has been devised in a preliminary way by Bernard M. The system, known as Cyclops, would consist of an enormous radio telescope connected to a complex computer system.

The computer system would be designed particularly to search through the data from the telescope for signals bearing the mark of intelligence, to combine numerous adjacent channels in order to construct signals of various effective bandwidths and to present the results of the automatic analyses for all conceivable forms of interstellar radio communication in a way that would be intelligible to the project scientists.

To construct a radio telescope of enormous aperture as a single antenna would be prohibitively expensive. The Cyclops system would instead capitalize on our ability to connect many individual antennas to act in unison. The Very Large Array consists of 27 antennas, each 82 feet in diameter, arranged in a Y-shaped pattern whose three arms are each 10 miles long.

The Cyclops system would be much larger. Its current design calls for 1, antennas each meters in diameter, all electronically connected to one another and to the computer system. The array would be as compact as possible but would cover perhaps 25 square miles.

The effective signal-collecting area of the system would be hundreds of times the area of any existing radio telescope, and it would be capable of detecting even relatively weak signals such as television transmissions from civilizations several hundred light-years away. Moreover, it would be the instrument par excellence for receiving signals specifically directed at the earth.

One of the greatest virtues of the Cyclops system is that no technological advances would be required m order to build it. The necessary electronic and computer techniques re already well developed. We would need only to build a vast number of items we already build well. The Cyclops system not only would have enormous power for searching for extraterrestrial intelligence but also would be In extraordinary tool for radar studies If the bodies in the solar system, for traditional radio astronomy outside the solar system and for the tracking of pace vehicles to distances beyond the each of present receivers.

Moreover, the argument in favor of eavesdropping is not completely persuasive. Half a century ago, before radio transmissions were commonplace, the earth was quiet at radio wavelengths. Half a century from now, because of the development of cable television and communication satellites that relay signals in a narrow beam, the earth lay again be quiet. Thus perhaps for only a century out of billions of years do planets such as the earth appear remarkably bright at radio wavelengths.

The odds of our discovering a civilization during that short period in its history lay not be good enough to justify the construction of a system such as Cyclops. It may well be that throughout the universe beings usually detect evidence of extraterrestrial intelligence with more traditional radio telescopes.

It nonetheless seems clear that our own dances of finding extraterrestrial intelligence will improve if we consciously attempt to find it. How could we be sure that a particular radio signal was deliberately sent by an intelligent being? It is easy to design a message that is unambiguously artificial. The first 30 prime numbers, for example, would be difficult to ascribe to some natural astrophysical phenomenon. A simple message of this kind might be a beacon or announcement signal.

A subsequent informative message could have many forms and could consist of an enormous number of bits. One method of transmitting information, beginning simply and progressing to more elaborate concepts, is pictures. One final approach in the search for extraterrestrial intelligence deserves mention. If there are indeed civilizations thousands or millions of years more advanced than ours, it is entirely possible that they could beam radio communications over immense distances, perhaps even over the distances of intergalactic space.

We do not know how many advanced civilizations there might be compared with the number of more primitive earthlike civilizations, but many of these older civilizations are bound to be in galaxies older than our own. For this reason the most readily detectable radio signals from another civilization may come from outside our galaxy.

The relatively small number of such extragalactic transmitters might be more than compensated for by the greater strength of their signals. At the appropriate frequency they could even be the brightest radio signals in the sky. Therefore an alternative to examining the nearest stars of the same spectral type as the sun is to examine the nearest galaxies. Spiral galaxies such as the Great Nebula in Andromeda are obvious candidates, but the elliptical galaxies are much older and more highly evolved and could conceivably harbor a large number of extremely advanced civilizations.

There might be a kind of biological law decreeing that there are many paths to intelligence and high technology, and that every inhabited planet, if it is given enough time and it does not destroy itself, will arrive at a similar result. The biology on other planets is of course expected to be different from our own because of the statistical nature of the evolutionary process and the adaptability of life. The science and engineering, however, may be quite similar to ours, because any civilization engaged in interstellar radio communication, no matter where it exists, must contend with the same laws of physics, astronomy and radio technology that we do.

Should we be sending messages ourselves? It is obvious that we do not yet know where we might best direct them. One message has already been transmitted to the Great Cluster in Hercules by the Arecibo radio telescope, but only as a kind of symbol of the capabilities of our existing radio technology.

Any radio signal we send would be detectable over interstellar distances if it is more than about 1 percent as bright as the sun at the same frequency. Actually something close to 1, such signals from our everyday internal communications have left the earth every second for the past two decades. This electromagnetic frontier of mankind is now some 20 light-years away, and it is moving outward at the speed of light.

Its spherical wave front, expanding like a ripple from a disturbance in a pool of water and inadvertently carrying the news that human beings have achieved the capacity for interstellar discourse, envelops about 20 new stars each year. We have also sent another kind of message: two engraved plaques that ride aboard Pioneer 10 and Pioneer These spacecraft, the first artifacts of mankind that will escape from the solar system, will voyage forever through our galaxy at a speed of some 10 miles per second.

Pioneer 10 was accelerated to the velocity of escape from the solar system by the gravitational field of Jupiter on December 3, Pioneer 11 swung past Jupiter on December 4, , and will travel on to Saturn before it is accelerated on a course to the far side of the galaxy. Identical plaques for each vehicle were designed by us and Linda Salzman Sagan.

Each plaque measures six by nine inches and is made of gold-anodized aluminum. These engraved cosmic greeting cards bear the location of the earth and the time the spacecraft was built and launched. The sun is located with respect to 14 pulsars. The precise periods of the pulsars are specified in binary code to allow them to be identified.

Since pulsars are cosmic clocks that are running down at a largely constant rate, the difference in the pulsar periods at the time one of the spacecraft is recovered and the periods indicated on the plaque will enable any technically sophisticated civilization to deduce the year the vehicle was sent on its epic journey.

Units of time and distance are specified in terms of the frequency of the hydrogen spin-flip at 1, megahertz. In order to identify thethe exact location of the spacecraft's launch a diagram of the solar system is given The trajectory of the spacecraft is shown as it leaves the third planet, the earth, and swings by the fifth planet, Jupiter.

The diversion of Pioneer 11 past Saturn had not been planned when the plaques were prepared. Last, the plaques show images of a man and a woman of the earth in An attempt vas made to give the images panracial characteristics.

Their heights are shown with respect to the spacecraft and are also given by a binary number stated in terms of the wavelength of the spectral line at 1, megahertz 21 centimeters. These plaques are destined to be the longest-lived works of mankind.

They will survive virtually unchanged for hundreds of millions, perhaps billions, of years in space. When plate tectonics has completely rearranged the continents, when all the present landforms on the earth have been ground down, when civilization has been profoundly transformed and when human beings may have evolved into some other kind of organism, these plaques will still exist.

They will show that in the year we called there were organisms, portrayed on the plaques, that cared enough about their place in the hierarchy of all intelligent beings to share knowledge about themselves with others.

How much do we care? Enough to devote an appreciable effort with existing telescopes to search for life elsewhere in the universe?

Enough to take a major step such as Project Cyclops that offers a greater chance of carrying us across the threshold, to finally communicate with a variety of extraterrestrial beings who, if they exist, would inevitably enrich mankind beyond imagination? The real question is not how, because we know how; the question is when. If enough of the beings of the earth cared, the threshold might be crossed within the lifetime of most of those alive today.