Scientists have given the answer to whether there is life on planets other than the earth in the universe.

So far, only the earth is the only planet with life, but it is undeniable that there may be other life forms in the vast universe. Nowadays, climate warming, ecological deterioration and other issues also urgently require human beings to find a planet similar to the earth. If a planet has water and oxygen, and the temperature is suitable, there may be life, which has reached the basic conditions for human survival.

Whether there is life on other planets besides the earth is also a topic that astronomical scientists have been exploring.

1974, information about humans and the solar system was merged into pictures. According to the standards of the 1970s, these pictures are high-tech products and look a bit like pictures in space games. Pictures are made to receive the intellectual life of information and convey what we want to express.

Arecibo radio telescope, Puerto Rico sends out signals with picture information. This telescope looks like a huge plate, and its position is in a big hole in the jungle.

Arecibo radio telescope can see a group of stars in the constellation Hercules, which is 2200 light years away from the Earth. According to this distance, those picture signals will reach 4 174.

If those stars have our kind, they will reply when they receive the message, that is, they will receive their letter on 4 174.

A few years ago, a potato chip company put forward a bold idea, and even wanted to advertise in Ursa Major, using the alien's desire to eat potato chips as a gimmick to increase exposure. Even if aliens really want to eat, it is estimated that it is difficult to send it.

There are really aliens in the universe. How do we communicate? Now the technology is developed, and the spacecraft only has radio signals of 1/20000. At this speed, it will take 80,000 years to fly to the nearest star.

Scientists suggest that it is best not to send advanced signals into space. If these signals are intercepted by aliens, they are likely to be cracked.

1890, humans began to study radio waves, and now the technology is developing rapidly, but the radio wave technology may not have reached a certain level. Maybe there is an interstellar broadcast in space, but we still can't get the signal.

Some people think that it is less likely to find the same kind or enemy in space, but aliens are not green dwarfs in space travel.

Where does the search for aliens in the universe start? We need to find elements that can sustain life, just as human beings can't live without food.

Life is inseparable from carbon and water, and so is life on earth, including all animals and plants. Carbon is the most important element in the periodic table. Of the100000 compounds, 9 million contain carbon.

The main reason is that carbon atoms are less than other atoms, arranged more closely together and can maintain a stable structure, so carbon is widely used in industry or agriculture.

Fortunately, China is rich in carbon resources. Even an ordinary star will not produce a lot of carbon until billions of years later.

As we all know, water contains hydrogen, which was produced in the Big Bang, and oxygen atoms can also be produced in stars. At present, except for the earth where humans live, water has been found, and no liquid water has been found on other planets for the time being.

Biologists study the living conditions of the earth and hope to find possible life on other planets, including aliens. However, space travel has certain limitations, that is, exploring several planets in the solar system and choosing a planet suitable for life.

The reason why people live on the earth is because it is in a suitable position, just in a superior orbital position. It is not too cold in winter and not too hot in summer, and most of the area is covered by liquid water.

For example, if Venus is too close to the sun, water will evaporate quickly and gas will be formed. Although it will rain, it is sulfuric acid rain, which rarely falls to the surface.

On the other hand, Mercury is too small to be affected by the solar wind for a long time, and its orbit is getting longer every day. Its surface is blocked by meteorites and in the shadow, and water can only exist in solid form.

Through the research of scientists, it is found that Mars is the most likely place for extraterrestrial life, and people even fantasize about moving to Mars one day.

1877, Italian Vanni schiaparelli seized the opportunity of Mars approaching the Earth in an astronomical observation. Through observation, he found a pattern similar to a canal on Mars, and drew a map of the surface of Mars according to what he saw.

That year, percival Lowell, a wealthy American businessman, spent a lot of money to build an observatory in Arizona, dedicated to observing Mars, hoping to find traces of Martians.

Although nothing meaningful was found, after Lowell's death, Pluto, the ninth planet, was found in this observatory.

Later, the Viking lander named after Italian scientist schiaparelli arrived in Mars, and found that the climate there was cold, a large desert, and there was no life at all.

However, scientists have not given up, thinking that the atmosphere of Mars is similar to that of the early Earth, and water once flowed. Perhaps the traces of life on it have been sealed into fossils, but the detector has not found them.

Europa is the second closest satellite to Jupiter, discovered by astronomer Galileo, and slightly smaller than the moon.

Its surface is not rock, but covered with ice. There is a heat source inside, which can produce volcanic hydrothermal activity. The ocean with liquid water at the bottom is about 10 km deep. This ocean covers the whole planet, even larger than the total volume of the oceans on the earth.

Many astronomers are curious that Europa has both heat source and liquid water. Is there life? To know the answer, we must first launch a lander on this satellite, and the structure of the lander is very special, half is a spaceship and half is a drill.

If you want to get into the ice covered on the surface, it is very difficult, and experts have also given suggestions, so it is best to find areas with cracks. Even if the detector can reach the alien ocean, there will be certain risks and pollution to the alien sea area.

How to collect alien water samples safely is a problem that scientists need to discuss at present, or bring the water samples back to earth and analyze them slowly.

In this vast universe, human beings are not alone. Maybe there is unknown life on other planets, but it has not been discovered. However, until that moment, scientists will not stop exploring. The earth, a living planet, may no longer be a lonely boat in a few years.