Why can't we 'encounter' aliens?

Are we the only creatures in this vast universe?

The reason we have never been able to meet aliens

The Milky Way where our Earth resides contains about 100 billion planets, and is one of hundreds of billions of galaxies in the universe. Therefore, logically, there must be at least millions of planets like Earth - that is, there exists life.

However, in a debate in 1950, physicist Enrico Fermi asked: If many advanced extraterrestrial civilizations exist in the Galaxy, why does the spacecraft or the probes not find? see?

And if there are millions of planets like Earth, why don't we know any other creature besides humans? This question later became classics and was named "Fermi paradox".

To answer the "Fermi paradox" , many scientists have come up with some theories about why we have not met aliens and you will be told after reading the article below.

1. Because the space is too large

The first and most widely known hypothesis - emphasizes the large space in the universe.

If the planet existed in the Milky Way, it could be thousands of light years from Earth. This makes communication in the universe impossible.

In addition, for other Galaxies millions of light years away, the ability to communicate is even more difficult. Many experts believe that the huge gap is the factor preventing our communication with "friends" from outside the Earth.

2. Do we find it hard enough?

So far, the search for extraterrestrial civilizations is very limited, because there are only a few telescopes located in many parts of the world. The Department of Search for extraterrestrial civilizations has also conducted many searches but has not found anything.

Therefore, in early 2015, a $ 100 million project was launched, called Breakthrough Listen . The project was invested by Russian fees, Yuri Milner.

Experts estimate that this will be the largest search for extraterrestrial life ever. The project will use two of the most modern radio telescopes in the world (the device is capable of amplifying, recording and determining the direction of radio waves).

These two devices can scan millions of stars and the nearest 100 galaxies to search for signals sent to our planet. Experts hope to find life beyond the Earth in the near future.

3. Great selection process - the Great Filter

However, the question is, if 10 years after starting Breakthrough Listen project, what will we still get?

This leads to the next hypothesis about the Fermi paradox - about the great selection process of the universe. The hypothesis says that the universe had a great natural selection, which caused civilizations to perish.

Proponents of this hypothesis suggest that if this selection process really exists, humanity may be the first species to cross. Or maybe we have not reached that landmark, while other civilizations before us have all perished.

4. We are alone in the universe

The last hypothesis we discuss here is also the scariest scenario: Man is completely alone in the vast universe.

In fact, the Earth has an orbit and a perfect distance from the Sun. This has brought the right temperature for life. But not only that, we also have to wait until the dinosaurs become extinct to appear on this planet. And even now, human civilization has only existed for a few thousand years; an extremely small part of the 13.8 billion-year-old universe.

This suggests that for humans to appear on Earth, the planet's ability to sustain life is not enough. So, is this the only place where civilization can exist?

Many experts do not believe this hypothesis. They believe we will soon find signs of microorganisms at the Solar System in the next few decades, and the near future will find further signals.

However, until we find evidence, we are still the only proof of cognitive creatures in the universe. That makes humanity and the Earth extremely special, but also makes the efforts of scientists become . hopeless.