You have about 4~6 liters of blood in your body. Your blood is very important for your health. Without enough healthy blood, your body will not get the oxygen and energy it needs. Also, healthy blood protects you from germs.
[호]
It's very hot in the summer. But it's very cold in the winter. So, why does the temperature change? This is because the Earth's axis is tilted. Many people believe that the temperature changes because the Earth is closer to the sun in summer and farthe
A black hole is the last phase in a massive star's life cycle. But to better understand this concept, you need to know about the life of a star. Stars are large hot bodies of hydrogen gas that burn brightly for millions or even billions of years through nuclear fusion. But not all stars are the same size. The size of a star is determined by its mass, which is the amount of gas that the star is made of.
We are living on Earth. But do you know how old is the Earth? It is a difficult question, right? But don't worry. In fact, no one knows the exact age of the Earth. Even the smartest scientists in the world can't answer this question easily! Well, some s
We can see the moon every night. But how much do you know about the moon? This week, let's learn some interesting facts about the moon. The moon is a little over 1/4 the size of the Earth, with a diameter of 3,476 kilometers. The
A typhoon is a tropical storm with winds that have reached a speed of 120 kilometers per hour. It is a violent tropical hurricane/cyclone that occurs in the west Pacific and the Indian Ocean. Typhoons are called hurricanes in the Atlantic, and cyclones in
Have you ever seen a falling star? Falling stars are also called shooting stars. You can sometimes see shooting stars in the night sky. Many people in the world think that seeing a shooting star is a good sign. Some people even believe that if you make a
The world is filled with colorful things. From red to purple, we can see many beautiful colors. However, some people are color-blind. It doesn't mean they can't see any color at all. It means that they have trouble seeing the difference between certain
Genes are the things that determine your physical traits. Each cell in the human body has about 25,000 to 35,000 genes. They carry information that helps make you who you are - curly or straight hair, long or short legs, even how you might smile are all p
After taking a bath, your fingers and toes wrinkle. Why does it happen? The outermost layer of the skin swells when it absorbs water. It is tightly attached to the skin underneath. So it compensates for the increased area by wrinkling.
[이전10개] 91 92 93 94
