The universe is a fascinating and amazing place, but it also has many misunderstandings and questions... Today, we will look at 14 facts about the universe that we are wrong about, and learn the correct information, as well as the scientific basis for it.

1. Mercury is the hottest planet in the solar system?

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Misunderstanding: Many people think that Mercury is the hottest planet in the solar system because it is closest to the sun.

Fact: Mercury is the closest planet to the sun, but Venus has a much higher temperature than Mercury due to the greenhouse effect caused by its thick atmosphere. Venus is as hot as being in a steamer, reaching 462℃, while Mercury is only about 167℃ on average, which is cool compared to Venus.

2. Black holes suck everything in?

Misunderstanding: Black holes are known as spaces where even light cannot escape due to their enormous gravity. For this reason, black holes are often misunderstood as sucking everything around them.

Fact: Black holes have a boundary called the event horizon. Everything that enters inside the event horizon cannot escape, but objects outside the event horizon are not affected by the black hole. Black holes do not suck everything around them, but they have a strong gravitational pull that makes surrounding objects move towards the center of the black hole.

3. There is no sound in space?

Misunderstanding: It is common to think that sound does not travel in space because it is a vacuum.

Fact: Sound travels through vibrations, and vibrations do not travel in a vacuum. However, there are vibrations in space caused by events such as black hole mergers or supernova explosions. These vibrations cannot be perceived as sound, but they exist as energy waves and travel through space.

4. Space is static?

Misunderstanding: In the past, it was thought that the universe was a static space that did not change.

Fact: According to modern cosmology, the universe is constantly expanding. In 1929, Edwin Hubble discovered that distant galaxies are moving away from Earth, and the farther away they are, the faster they are moving away. This means that the universe is expanding.

5. The moon has a dark side?

Misunderstanding: Some people think that one side of the moon does not receive sunlight and is always dark.

Fact: The moon has a rotational axis, and its rotation period is 27.3 days. One side of the moon faces the Earth, so it always seems to be facing us, but in reality, all sides of the moon are illuminated by sunlight. The back side of the moon is simply the side we cannot see, not a dark side.

6. Polaris always points north?

Misunderstanding: Polaris is located in the northern sky and is known as the star that always points north.

Fact: Polaris is located almost in line with Earth's rotational axis, so it appears to be almost stationary in the northern sky. However, Earth's rotational axis slowly changes direction over a period of about 26,000 years. Therefore, Polaris will gradually change its direction of pointing north over time.

7. Astronauts just float around in zero gravity?

Misunderstanding: We often see astronauts floating freely in zero gravity in movies and TV shows.

Fact: Astronauts are still under some gravity even in zero gravity. Also, the inside of a spaceship is sealed, so there is no air resistance, which can make movements appear slow. However, astronauts still need to use force to grab or move objects. Think of it as being able to move around in water with some resistance, but freely.

8. There is no water in space?

Misunderstanding: Some people think that there is no water in space because it is mostly a vacuum.

Fact: Recent research has shown that there is much more water in space than we thought. In particular, water has been found in comets, satellites, planetary atmospheres, and even the center of galaxies. Water is an essential element for the existence of life, so the fact that water exists throughout the universe increases the possibility of finding extraterrestrial life. Just like you can find an oasis in a desert, water can also exist in space.

9. There are no aliens in space?

Misunderstanding: In the past, there was a lot of debate about the existence of aliens, but currently, the opinion that aliens do not exist is dominant.

Fact: In recent decades, scientists have discovered numerous planets outside the solar system where there is a high possibility of liquid water. Also, some planets have been found to meet the conditions for life to exist. Therefore, there is no definitive evidence that aliens do not exist, and further research may reveal the existence of extraterrestrial life in the future. Just like there are creatures in the sea that have not yet been discovered, there may be extraterrestrial life in space that we do not know about.

10. Space travel is incredibly expensive?

Misunderstanding: In the past, space travel was a privilege only for billionaires, but with the advent of the private space travel era, costs are gradually decreasing.

Fact: In recent years, private space companies such as Elon Musk's SpaceX and Jeff Bezos' Blue Origin have been actively investing in space tourism. Due to their efforts, it is expected that more people will be able to experience space travel in the future. In the past, air travel was incredibly expensive, but with technological advancements and increased competition, many people are now able to enjoy air travel. However, it is still expensive for ordinary people.

11. There is a lot of garbage in space?

Misunderstanding: People think that space is filled with garbage caused by human activities, such as satellites and rocket launchers.

Fact: Space is so vast that the space occupied by all the artificial objects launched so far is a tiny fraction of the entire space. However, space debris can pose safety hazards, such as satellite collisions, and lead to space pollution in the long run. Therefore, efforts are needed to solve the problem of space debris. Just as garbage thrown into the sea has a negative impact on the marine ecosystem, space debris can also have a negative impact on the space environment.

12. Space is completely dark?

Misunderstanding: Some people think that space is completely dark because it is a vacuum and light does not travel there.

Fact: There is light in space emitted from stars, galaxies, planets, etc. Also, there is a faint light called cosmic background radiation that fills the entire space. These lights are different from the starlight we can see in the night sky, but space is not completely dark. It is similar to how the night sky is not completely dark, and there is faint moonlight and starlight.

13. Space exploration is a waste of money?

Misunderstanding: There are criticisms that space exploration is a waste of money because it does not directly benefit humans.

Fact: Space exploration contributes to scientific and technological advancement, discovers new knowledge, and opens up possibilities for the future of humanity. Also, space exploration can enhance our understanding of the space environment and help solve Earth's environmental problems. Just as past explorations have brought new knowledge and technological advancements, space exploration will play an important role in the future of humanity.

14. Space is a dangerous place for humans?

Misunderstanding: People think that space is a dangerous place for humans because of its extreme environment.

Fact: While there are dangers in space, they can be minimized with proper preparation and technology. Also, space exploration can help increase human survival. Just as the sea is a dangerous place, but we can sail safely with proper preparation and technology, space will become safer in the future as we prepare thoroughly and technology advances.