Invented by Galileo.
During the 18 years that Galileo worked at the University of Padua, he initially focused his main energy on the mechanics research that he had always been interested in. He discovered an important phenomenon in physics-the inertia of the motion of objects; he did a famous slope practice and concluded The quantitative relationship between the distance the object falls and the elapsed time; he also studied the movement of the cannonball, laying the foundation of the parabolic theory; the concept of acceleration was also the first one he clearly proposed: even to measure the patient’s fever With the increase in body temperature, the famous physicist also invented the first air thermometer in 1593… However, an accidental event caused Galileo to change the direction of his research. He turned from the study of mechanics and physics to the vast expanse of space.
It was the winter of 1604. An unusually bright star suddenly appeared in the southern sky. This uninvited guest of the universe attracted the attention of many people, and then mysteriously disappeared in the autumn of the following year. People can’t help asking a series of questions, what kind of star is this? Where does it come from and where does it go? What kind of law does the little stars in the night sky move? However, no one knows all these questions.
Galileo is observing the mysterious star every night. As long as the weather is clear, he will never let go of this golden opportunity. Many questions continue to come up in his mind, and he feels more and more that mankind knows too little about the secrets of the universe.
However, observation with the naked eye is limited after all, and the telescope was not invented at that time. Galileo has been wondering whether he can think of ways to make people’s eyesight sharper and more extended, so that they can see distant stars like the clairvoyance in mythology?
In a blink of an eye, in June 1609, Galileo heard a news that Lipasi, a spectacles merchant in the Netherlands, used a lens to see something invisible to the naked eye in an occasional discovery. “Isn’t this the clairvoyance I need?” Galileo was very happy. Soon, a student of Galileo sent a letter from Paris to further confirm the accuracy of the news. The letter said that although I don’t know how Lipaci did it, the eyeglass merchant must have made a mirror tube with which the object can be magnified. Many times.
“Mirror tube!” Galileo read the letter several times and hurried into his laboratory. He found paper and a goose-tube pen, and began to draw a schematic diagram of lens imaging after another. Galileo was inspired by the tip of the lens tube. It seems that the secret of the lens tube’s ability to magnify objects lies in the choice of lens, especially how to match the convex lens and the concave lens. He found information about the lens and kept calculating, forgetting that the twilight climbed up the window, and how the dawn shot into the room.
After a whole night, Galileo finally understood that putting the convex lens and the concave lens at an appropriate distance, just like the Dutchman saw it, the distant objects invisible to the naked eye can be seen clearly after magnification.
Galileo was very happy. He ignored the rest and immediately started to polish the lenses, which was a very time-consuming and careful task. He worked for several days, grinding a pair of convex and concave lenses, and then made an intricate sliding double-layer metal tube. Now, it’s time to test his invention.
Galileo carefully installed a larger convex lens on one end of the tube and a smaller concave lens on the other end, and then pointed the tube out the window. When he looked from one end of the concave lens, a miracle appeared. The church in the distance seemed to be close in front of him, and the cross on the bell tower could be clearly seen. Even a dove resting on the cross looked very realistic.
The news that Galileo made a telescope was posted. “The news that I made a telescope came to Venice.” In a letter to his brother-in-law, Galileo wrote: “A week later, he ordered me to present the telescope to the Speaker and Members of Parliament. They were very surprised. Gentlemen and Members, although they are very old, they all boarded the highest bell tower in Venice in order and looked at the ships far away from the harbour. They could see clearly. Without my binoculars, they would be out of sight for two hours. The utility of this instrument can make objects 50 miles away look like they are within 5 miles.”
The telescope invented by Galileo has been continuously improved and the magnification has been increased to more than 30 times, which can magnify the real object by 1000 times. Now, as if he had clairvoyance, he could pry into the secrets of the universe.
This is an epoch-making revolution in the study of astronomy. For thousands of years, the era of astronomers observing the sun, moon and stars with the naked eye is over. Instead, optical telescopes have emerged. With this powerful weapon, modern astronomy The door was opened.
Now, every night when the stars are shining or the moon is in the sky, Galileo will aim his telescope at the deep and distant sky, regardless of fatigue and cold, watching night after night.
In the past, people always thought that the moon was a smooth celestial body, shining on itself like the sun. But Galileo found through a telescope that the moon, like the Earth we live on, has high mountains and low depressions (at the time Galileo called it the “sea”). He also moved from the bright and dark parts of the moon, and discovered that the moon itself does not emit light. The light of the moon comes through the sun.
Galileo pointed the telescope at the Milky Way that traverses the sky. People used to think that the Milky Way is a white mist formed by water vapor on the earth, and Aristotle thought so. Galileo decided to use a telescope to test whether this statement was correct. He pointed the telescope at the foggy light band in the night sky, and he couldn’t help being taken aback. It turned out that it was not a cloud at all, but a cluster of thousands of stars. Galileo also observed the speckled clouds in the sky-the so-called star clusters, and found that star clusters are also many stars gathered together, such as the Orion star cluster, the Taurus star cluster, and the honeycomb star cluster.
Galileo’s telescope has revealed the secrets of the universe one after another. He discovered the moons orbiting Jupiter and calculated their cycle. Now we know that Jupiter has 14 moons, and Galileo has discovered the largest four of them. In addition, Galileo used a telescope to observe sunspots. He inferred from the movement of sunspots that the sun is also rotating.
One inspiring discovery after another enabled Galileo to write a book about the latest astronomical discoveries, and he wanted to announce his observations to the world. In March 1910, Galileo’s “Interstellar Messenger” was published in Venice and immediately caused a sensation in Europe.
However, he did not expect that the secrets of the universe revealed by the telescope greatly angered many people, and a terrible bad luck was about to fall on this outstanding scientist.
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