10 facts about the search for extraterrestrial life

In 1950, the Nobel prize winner Enrico Fermi asked his colleagues over lunch the famous question: where is everyone? This question became known as the Fermi paradox. Fermi wanted to know why we have not yet met any aliens, if the Universe so many potentially habitable planets?

There are many theories as to why we still have not come to anyone in contact. However, it may be that we just made a space error in their calculations. We started with the assumption that extraterrestrial life will be similar to ours. If this assumption is erroneous, all of our calculations regarding the search of alien life will have no meaning. Therefore, we begin to change that initial assumption, expanding their thinking and strategies on finding those who can be our friend. Or enemy.

Sunset radio waves SETI

More than 50 years, SETI is listening for radio in search of signals from space. In 1974, astronomer Frank Drake sent the first radio message, "the Arecibo Message", the aliens in the outer space. As far as we know, the answer did not come. If you listen to NASA today, it may seem that the search for alien life is a priority for space agencies. However, Drake is complaining that NASA is not really funding the search. In addition, the Agency can dismantle our two largest radio telescope, Arecibo and Green Bank. If this happens, SETI will roll initiative on the part of the radio. And although China has presented a sophisticated radio telescope, Drake is not sure that technology will work correctly and meet certain requirements.

On the other hand, optical SETI (SETI stands for "search for extraterrestrial life"), who is looking for a laser flash, is well funded mainly by private donations. Unlike radio wave communications, optical communications, we will be able to get if the aliens will send their narrow laser beams right at us. "These signals are so strong that we only need a small telescope to detect them, says Drake. Small telescopes can offer more time for observation, and this is good because we need to examine a number of stars, increasing the chances of success". Drake used to think that if aliens seek to find us, they can be friendly.

But not everyone shares his optimism. Experts engaged in heated debate about whether we need to do to send messages in the outer space. Many believe that we put the threat to our own security by trying to communicate with aliens, not providing yourself adequate protection. According to John Elliott of SETI, the SETI community still have members that send signals, despite the danger of this activity. Drake himself opposed to actively sending signals to potential guests in the framework of the initiative "active SETI."

A conversation with инопланетянами

John Elliott of the British network search SETI believes we must go beyond the search for extraterrestrial signals, and start to tell the difference between a foreign language and random sounds. Studying more than 60 human languages, he found a common signature rhythms and structures in each language. For example, we have words that carry meaning, and short functional words (like "if" and "but") that link phrases together. Regardless of the language people use no more than nine semantic words in the same sentence.

Some animal species like dolphins have a similar feature in the language. And although we are not yet able to speak the language of dolphins, we recognized 140 different sounds in their speech. They always identificeret a separate name or cry when you start talking, giving no more than five words in a phrase. Elliott believes that this limitation is due to smaller brain size and ability to process information.

He developed a series of small computer programs, Natural Language Learner to analyze the signals of aliens in complexity and internal structure of the language. Obviously, while it could not be deciphered.

Communication with intelligent animals on Earth can be the first step towards developing our ability to communicate with aliens. We taught dolphins hundreds of our words, the difference between a question and statement, concepts like "none" and another syntax. As a first attempt to install two-way interactive communication between animals and humans biologist Denise, Herzing created a game in which dolphins and people need to learn to talk to each other using a primitive language. Female dolphins were more interested in the game than males. Female dolphins also invited the dolphins other species to join her.

We also learned that wild monkeys Campbell add suffixes to certain sounds to warn others of the dangers. For example, the signal "crack" means that a number of leopards, their natural enemy. But "crack-Oh" just warns him of danger, like falling branches or invading other apes in their territory. Diana monkeys also understand the cry of the monkeys Campbell.

Another study showed that adult chimps from the Netherlands slowly changed their language to fit the local chimps, after moving to Scotland and made friends with the local animals. However, it is unclear whether it was learning a second language, evidence of bilingualism, or the change of accent.

Fun style 1015 BC

The success of the search for extraterrestrial life depends on the technology of extraterrestrial life uses to send signals. Although creatures using technology, can be reasonable, the reverse is not always true. Back to the intelligence of dolphins. Dolphins have no limbs to invent and use complex tools, but they are pretty smart. Other types of extraterrestrial life can be like. So is the use of technology or communication and socialization determines intelligence?

Are we too arrogant in believing that intelligent creatures such as dolphins? Carl Sagan noted that "while some dolphins have learned English — up to 50 words used in correct context — no one has studied the Dolphin". Also they don't use technology to kill each other.

To prepare for contact with aliens, Lawrence Doyle from SETI also intends to explore the communication between trees. They use chemicals to communicate with each other about the pests and other threats. "Who knows? The brain does may not be needed," he says.

In either of these two cases, we would have to go to a place where aliens live, and not to wait until they contact us.

The fact that we don't hear aliens, maybe the reason is simpler, even if they look like us. When we use telescopes to see outer space, we see things not as they are now. "We are looking back in time because light takes time to get from here to there, explains Jonathan Gardner from NASA. — So when we look farther, you need more and more time for light to get from where it was emitted here; we are in fact peering back in time. And if we look far enough we can see those days when the universe was much younger than today when the light was only emitted by these galaxies".

If aliens are watching us through telescopes, they can see us in the past too. For example, aliens living in 1000 light years from us, sees us in the year 1015 ad. Since radioserial was invented only in 1907, you will need at least another 900 years before the aliens can catch the radio signals from Earth (if they even use this technology).

Sociologists решают

Usually we are talking about the exact Sciences — astronomy, computer science, engineering, physics — in the context of communication with aliens in space. But Doug Vakoch, Director of interstellar communications, the SETI Institute, maybe something to tell about the archaeology, anthropology and interstellar communication from the point of view of sociologists.

Every day, archaeologists and anthropologists trying to uncover the secrets of ancient civilizations on scraps of information. We will never be able to know if they are accurate in their interpretation. Too often we base our conclusions about civilizations of the past on the thoughts of our modern cultures. But at least we have a common human ancestor. How do we decode the messages of extraterrestrial cultures about which we know nothing of aliens, which can have additional senses?

We also assume that extraterrestrial civilizations will be one culture. But in fact it may be the only common thread between humans and aliens. "We must recognize the fact that we could deal with the world broken into different cultural paradigms, like ours, and consisting of beings who may not respond to touch, as it should, believes John Traphagan. — Technological advances on Earth have always been associated with political and social integration (recall the Second world war). It seems reasonable to assume that we're going to be dealing with beings who share common memories (among themselves), but also arguing and fighting, producing ideas within this shared memory and to retrieve the experience of everyday communication, as do the people."

Simply to say that we have no hope to decipher the conversation of the aliens in our usual manner.

Heat сигнатуры

Using data from 100,000 galaxies observed by the spacecraft WISE, scientists have searched for heat signatures that could indicate the existence of advanced alien civilizations. "Using advanced, mastering space, civilization, huge amounts of energy of stars in their galaxies to fuel computers, vehicles, flight, relationship or something beyond our imagination, the fundamental thermodynamics tells us that energy must be emitted as heat medium infrared waves, says researcher Jason Wright of the University of Pennsylvania. The same basic physics leads to the fact that your computer heats up when working."

Unfortunately, scientists have not found conclusive evidence of an advanced civilization. And it's strange, given the fact that galaxies could exist for billions of years. Incidentally, they were supposed to be filled with aliens. Scientists came to the conclusion that either aliens are not here, or they simply are not developed enough to show the heat signature.

For all that scientists have found 50 galaxies with an incredibly high level of radiation in the mid infrared spectrum. It is necessary to conduct additional research to find out what the source of this heat: natural or man-made.

Modest инопланетяне

Although we don't say it out loud, our assumptions about the aliens include the belief that they have unlimited resources with which they work. It seems to us that they have every day to send us signals. If not, the aliens not.

It's human pride in all its glory. If NASA has to cut its funding, why the aliens can't meet with the same problem? In 2010, the study of Microwave Sciences showed that the aliens can send signals at a higher frequency than we think. SETI scientists are listening in the wavelength range of 1.42–1,72 GHz, because certain interstellar clouds emit radiation at this frequency. However, the researchers Microwave Sciences believe that aliens are more likely to use a frequency of about 10 GHz, because they create a powerful beam of waves of this frequency is easier and cheaper.

To save resources, the aliens are most likely to transmit short pulses, similar to tweets on Twitter, rather than issue a continuous signal. Perhaps the aliens would have built a powerful beacon and turned it in to the disk of the milky Way to give the signal for the most stars in the galaxy. Thus, they could send a 35-second burst of pulses on every star within 1080 light-years.

But such an approach would have been to send a signal only a few times a year. "Astronomers have seen some unexplained signals that lasted for tens of seconds, but then never repeated, says Benford. Some of them could be sent to extraterrestrial beacons, but didn't have enough observing time to wait for the repetition of signals".

It is, in principle, can explain the 72 second WOW signal recorded by SETI scientists in 1977. Some scientists believe that it was a message to alien civilizations. The WOW signal it is called because the person who heard it, wrote "Wow" in the margins of his notebook. It is unknown where and what it was. Never heard of it.

DNA on the other основе

At the core of our beliefs lies with the fact that water is essential for life. But now scientists are studying whether other liquids like methane, covering the moon of Saturn Titan, to be the basis for life. We need different types of molecules, ethers to produce the vital chemical interaction, and in conditions warmer than the Titan. Taken together, ethers can be combined in complex polyesters and to give rise to living things. Molecules DNA and RNA that exist on Earth, insoluble in hydrocarbons.

Like water, hydrocarbons can be liquid, solid or gaseous. Solid and gaseous hydrocarbons will not allow biomolecules to interact and create a life, so you need to look for liquid hydrocarbons — such to itself "oil" Land. Octane remains liquid for a large temperature range, providing the most favorable conditions for life. Methane and propane are also working, but in a smaller temperature range. Unfortunately, all the evidence suggests that Titan too cold to support life.

"In our own Solar system we have planets that will be big enough and close enough to the Sun, with the right temperature to maintain the hydrocarbon oceans on the surface," says Steven Benner of the Foundation for applied molecular evolution. However, given the number of new solar systems that we find, very soon we can detect the planet with life, splashing in oceans of hydrocarbons.

Scenario контакта

Although it is unlikely that we will be face to face with intelligent aliens in a short time, it is possible that they live underground on one of the planets or moons in our Solar system. They can also inhabit the asteroid belt.

In 1950 the U.S. military developed the "Seven steps to contact," the plan to perform the first contact with intelligent aliens. First, we must study them from afar and gather as much data as possible. Then we have secretly come to evaluate the level of weapons and vehicles. If our technology will be better, we have to approach the planet of aliens, to see how they are hostile. If it doesn't, you need to briefly land in a remote and uninhabited area of the planet to take samples of plants and animals. The military also instructed to abduct a few aliens, not harm them.

After that, we must take weak approaches to the aliens noticed us, but staying out of reach. It would be better if a lot of the aliens looked at our ship, but to make us look friendly. Finally, if we decide that it's safe, we can land and meet with them.

This procedure remains virtually unchanged, but the day when we can use it on the way. It's unclear what will happen if we are faced with the higher mind. Let's hope he will be friendly. If not, you'll have to tear the claws.


When we look for life on other planets, we usually try to detect biochemical signature. However, our methods often give false positive result.

Scientists MIT Sara Seager and William Bain think we should expand the search beyond the known methane, oxygen and other biosignatures. "We know that there are not many easily accessible planets — says Seeger. We want to make sure that do not miss any signatures, trying to go beyond the usual things. Oxygen is a great biosignature gas for the Earth, but what are the chances that he will be attending exoplanet?".

Promoting the idea that extraterrestrial life may be very different from us, Seeger and Bane point out the "zoo" of diverse exoplanets that we've discovered at the moment. "A very interesting conclusion that the most common type of planets in our galaxy — planets the size between Earth and Neptune — a new class of planets that is neither terrestrial or giant planets, there is also no accepted theory of their formation," wrote Seeger and Bane.

To go beyond these limitations, scientists from Belgium and Switzerland recently experienced a new device that detects life without defining biosignature. Using the cantilever (beam fixed at one end), the detector nonadiene scanning the surface looking for small fluctuations in the metabolic activity of the cells or their movements. Scientists successfully tested their device on bacteria, human cells, mice and cells of plants and yeast. They then killed the cells and again tested to make sure that the device can correctly distinguish between a live signal from the dead. This nanosensor also successfully coped with the soil samples and the water containing the microorganisms. On the Ground, the experiment takes about 10 minutes.

Although it is necessary to conduct additional studies, detector anodizing could be a breakthrough method of searching for extraterrestrial life. It is simple, fast, small, and does not require biochemical information. If we combine this with biochemical sensors, we have a pretty powerful way of finding life in places like the moons of Saturn.

The best place to find жизни

For the most part ignoring the outer Solar system, we spend a lot of resources on the exploration of Mars, hoping to find alien life there. It is possible that on Mars we will find it. But the icy moon like Enceladus (Saturn), Europa (Jupiter) and Ganymede (Jupiter) is in the outer part of our Solar system may have high chances for the maintenance of life. Many of these satellites have underground oceans.

"Currently five orbiters and two robot exploring Mars, says Corey Powell of Discovery magazine. — But how many robots are exploring four of the moon: Europe — 0, Ganymede — 0, Enceladus — 0 Titanium — 0. We could search for life in General in all the wrong places".

One of the reasons why we ignore the outer Solar system, is the time and money needed to get to her. To Mars we can get on average for eight months. But you may need six to eight years to reach Jupiter and Saturn, respectively. However, on Saturn we have already sent the spacecraft Cassini, while the Clipper will be launched in Europe in 2022. The Hubble space telescope and the probe Galileo also collect information on Ganymede and Enceladus.

At the moment the best place to look for extraterrestrial life may be Enceladus. In addition to the liquid water that exists under the icy crust of the moon's surface, scientists have discovered evidence of activity at hydrothermal vents on the seabed of the satellite. Heat and water are important parts of life. In addition, the underground ocean of Enceladus must be in contact with the mantle of the moon, and then water is mixed with rich minerals like sulfur. Although the alkalinity of this water is fairly high with a pH of 11-12, life on Earth can be formed in similar alkaline conditions.published


P. S. And remember, only by changing their consumption — together we change the world! ©

Source: hi-news.ru


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