宇宙飛行士が宇宙で泣くとどうなる？
In space, because there is no gravity like on Earth, tears do not fall down the face. Instead, they gather around the eyes and form little balls of water. If an astronaut cries a lot, the water balls can cover the eyes and make it hard to see. Crying in space can be a big problem!
ペトラ遺跡はどうやって作られた？
Petra, located in Jordan, is called the "Rose City" and was built about 2,000 years ago by the Nabataeans. Amazingly, many of Petra's structures were carved directly into rock. They used tools like chisels and hammers to create beautiful temples and tombs. Recent studies show that they even designed an advanced water system to support the city.
蜃気楼（しんきろう）はなぜ見えるの？
Mirages happen because light bends when it passes through air layers of different temperatures. For example, in a hot desert or on a heated road, the air near the ground is much hotter and lighter than the air above it. Light bends along this difference, making it look like there are pools of water or reflections. A mirage is actually a kind of optical illusion!
アンコールワットの隠された秘密
Angkor Wat, located in Cambodia, is one of the largest religious structures in the world. It was first built as a Hindu temple, but later became a Buddhist temple. Recent research has revealed that a huge ancient city was hidden around Angkor Wat. Underground, there are roads, houses, and reservoirs. Angkor Wat was actually the center of a grand city.
宇宙に音は聞こえるの？
In space, you cannot hear any sounds. That is because sound needs something like air or water to travel through. Space is almost a vacuum, so there is nothing to carry sound waves. However, with special machines, scientists can change the vibrations from gas and plasma into sounds. So, in a way, space does have "voices," but we cannot hear them with our ears alone.
世界一小さな哺乳類 ― キティホエールコウモリ
The world's smallest mammal is called Kitti's hog-nosed bat, and it lives in Thailand and Myanmar. This tiny bat is only 3 to 4 centimeters long and weighs just about 2 grams! Even though it is very small, it can fly quickly and catch insects to eat. During the daytime, it rests in caves. At night, it goes out to hunt for food. Its super small size and amazing life skills have fascinated scientists all over the world.
宇宙服のひみつ
Space suits are not just clothes. They work like tiny spaceships to protect astronauts. In space, there is no air, and the temperature can be extremely hot or cold. Space suits give astronauts oxygen, control their body temperature, and protect them from dangerous radiation. Also, some suits have small engines to help astronauts move in space because they can't move without pushing against something.
流れ星って本当は何？
A shooting star looks like a bright streak across the night sky. But it’s not really a star! It’s actually a small piece of rock or dust from space. When it enters Earth's atmosphere, it burns up and makes a bright light. Most shooting stars are very small and burn away completely before they reach the ground. It's a quick, beautiful moment—like a little gift from the universe!
タマゴは丸くない？上下がある理由
Eggs look round at first, but they actually have a pointy end and a round end. This special shape has a purpose. The pointy end helps keep the egg from rolling away in the nest. The round end gives more room for the chick to grow inside. Also, this shape helps the egg move smoothly inside the bird's body. It’s a great example of how nature designs things in a smart way!
なぜ空は青くて夕焼けは赤いの？
When sunlight enters Earth’s atmosphere, it gets scattered by the air. Blue light is scattered more than other colors because it travels in shorter waves. That’s why the sky looks blue during the day. But during sunset, the sun is lower in the sky and the light has to pass through more air. Most of the blue light is scattered away, so the red and orange colors become stronger. This is why sunsets often look red or orange.
眠っている間に体がビクッとなる理由
Have you ever felt your body suddenly jump just as you were falling asleep? This is called a “sleep start” or “hypnic jerk.” It happens when your body is relaxing and your brain gets confused. It may think you’re falling, and it quickly tells your muscles to move. That’s why your body jerks! This often happens when you’re very tired or stressed. It’s completely normal and happens to many people.
コンパスの誕生と歴史
The compass was invented in ancient China during the Han Dynasty (2nd century BC to 1st century AD). Initially, it was used for divination as a "south-pointing fish" made of magnetized material. By the Song Dynasty (960–1279 AD), it became a vital tool for navigation and military purposes. The compass reached Europe around the 12th century, significantly advancing maritime exploration. With the compass, sailors could determine directions without relying on landmarks or celestial bodies, paving the way for the Age of Discovery.
マリー・キュリーとノーベル賞
Marie Curie won the Nobel Prize in Physics in 1903 and the Nobel Prize in Chemistry in 1911. She is known for her research on radioactivity and discovered two new elements: polonium and radium. Madame Curie was the first person to receive two Nobel Prizes, and she played an important role in raising the status of women in science.
ローマ帝国の道路網
The ancient Roman Empire built approximately 80,000 kilometers of roads. These roads were essential for moving armies and supporting trade, helping to govern the vast empire efficiently. One famous road, the Appian Way, was constructed in 312 BCE and parts of it still exist today. The Roman road system gave rise to the saying, All roads lead to Rome.
くしゃみのスピードは時速160km！？
When we sneeze, the air that comes out of our nose and mouth can reach speeds of up to 160 kilometers per hour! That’s as fast as a bullet train in Japan. A sneeze is very short?it lasts less than a second?but it is very powerful. Because sneezes can spread germs quickly, it’s important to cover your mouth with your hand or elbow when you sneeze. This simple habit can help protect the people around you!
鏡にうつる自分は左右が逆なの？
When you look into a mirror, it may seem like your left and right sides are switched. But actually, a mirror doesn’t flip left and right. It flips front and back. For example, if you raise your right hand, your reflection also raises its right hand. It only looks reversed because you are facing the mirror. This is a strange but interesting effect that happens because of how we see and think about directions.
木星の巨大な嵐「大赤斑」
Jupiter has a huge storm called the “Great Red Spot.” This storm is so big that two or three Earths could fit inside it! It has been going on for over 350 years, making it one of the longest-lasting weather systems in the solar system. The wind speed inside the storm can reach up to 430 kilometers per hour. Scientists are amazed by how long it has lasted. No one knows for sure why the spot is red, but it may be caused by chemicals in Jupiter’s atmosphere.
消しゴムの歴史
Erasers we use every day were originally made from natural rubber. In 1493, Columbus saw people in the Americas making bouncing balls from rubber and brought it back to Europe. However, natural rubber had problems?it became sticky in summer and hard in winter. In the 1950s, Japan developed plastic erasers using vinyl chloride, which are now commonly used.
