Nearly a century of space exploration pays tribute to a group of brave people who look up at the stars.

In this era, scientists and even human beings have two most concerned issues about the universe. One is, "Are there any planets like the Earth around other stars?" The second is "What is dark matter?"

These two questions are based on human exploration of the universe for nearly a century. For the vast universe, this is a job that human beings don't know where the end point is.

But what's the harm? For a long time, human beings have been curious about the starry sky and the universe overhead. Exploring the universe has also achieved a great leap in science and technology, and human cognition is constantly improving.

As Raymond, chairman of Rockefeller Foundation, said, "The vastness of the universe is beyond human imagination. But we humans spend all our energy fighting for something with our compatriots. As long as we simply look at it with this telescope, we will know that those things are simply insignificant. "

The telescope in his mouth is also the protagonist of this book, Paloma Observatory and its telescope. Scientists call it "giant eyes", accompanied by a group of outstanding scientists with infinite curiosity, who have super insight, superb skills, courage and creativity. They often compete with each other, but they also cooperate with each other to promote human cognition of the universe with their life-long energy.

Recently, I read a wonderful book "One Hundred Years of Space Exploration", which not only recorded the scientific course of astronomers exploring the mysteries of the universe at Paloma Observatory, but also paid high tribute to these scientists who had great dreams of exploring the universe.

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Edge outpost of the universe

Summon the explorers.

Throughout the history of astronomy, the early Mount Wilson Observatory laid a very important foundation, and the later Paloma Observatory played a very key role in the later development of astronomy.

I have to mention George ellery Hale, the founder of Paloma Observatory. He devoted his life to collecting more light from the universe and presided over the construction of the world's largest telescope four times.

He first built an etheric 40-inch refracting telescope for the Leaves Open Observatory near his hometown of Chicago, which broke the record of the largest telescope in the world for the first time (it is still a behemoth of its kind).

Later Haier realized that he had made a mistake. The local area is located in the Great Lakes region. It is often foggy and the weather is not good, which leads to the telescope being idle.

He immediately left the Great Lakes and went to Wan Li's clear sky and hilly southern California. Mount Wilson Observatory was built on a hill near Pasadena, and two reflecting telescope were built for it.

1908, he first built a 60-inch telescope. Nine years later, he built the second 100-inch telescope and named it Hook.

In fact, Haier knows in his heart that the grand cause of building the world's largest telescope will never stop at the Hooke telescope with a size of 100 inch. His dream is to build a bigger telescope one day.

1928, Haier published an article in Bazaar of Fashion, which contained a passage: "The distant outpost of the universe, like a buried treasure, has been calling explorers since ancient times." But unfortunately, due to physical reasons, he could not see the day of his inauguration.

Later, with the support of Rockefeller Foundation, this 200-inch telescope settled in Paloma Mountain Observatory, and the media called this behemoth "Giant Eye". This magnificent instrument attracted astronomers here.

Pictured: Paloma Observatory

And this "giant eye" in the eyes of everyone, with Haier's ambition to explore the universe, launched an unexpected exploration. It quickly became an important partner in the booming radio astronomy and infrared astronomy, and played a key role in determining the sources of gamma-ray bursts and X-ray bursts and describing their characteristics.

This big telescope has fulfilled its promise, bringing hope to astronomers and physicists and making the universe within reach. While scientists are eagerly looking forward to it, they are also planning how to best explore the great mysteries of the universe.

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The two giants cooperated with each other.

Make an amazing discovery

After the completion of Paloma Observatory, it was Fritz Zwicky, a Swiss physicist in the 20th century, who really laid the foundation for the scientific achievements of the Observatory. He played a key role in the whole astronomical research. He received his doctorate in X-ray crystallography from the Federal Institute of Technology in Zurich, and then worked at Mount Wilson Observatory.

He found that the 60-inch and 100-inch telescopes at Mount Wilson Observatory had small fields of view, and only a few galaxies could be photographed at a time. According to this progress, how can astronomers find celestial bodies worth exploring and studying? This problem later turned around.

Pictured: Mount Wilson Observatory

1929, an optical instrument engineer named bernhard Voldemar Schmidt invented a perfect tool. He found a way to correct the optical defects of fast large field of view mirror-insert a special correction glass plate into the beam.

In this way, he built a camera prototype, which can not only shoot wide-angle images, but also image clearly, even at the edge of the field of view. Successfully solved these problems that Zwicky saw.

1In the early autumn of 950, Bud, an important employee of Mount Wilson Observatory, went to Paloma Mountain and took the first picture of Andromeda galaxy with a 200-inch telescope. There is a refrigerator in the dome to store photographic negatives coated with emulsion sensitive to blue light.

Bud loves to observe, works meticulously and has excellent skills. He only observes when the weather is at its best. He would rather keep the world's largest telescope waiting all night than use it to look at the twinkling stars.

This time, he chose the measurement results of photoelectric cell to compare the size of Hubble Cepheid variable. The result of photoelectric photometry is more accurate, from which the distance of M3 1 (Andromeda galaxy) is calculated, which is twice as different as that calculated by Hubble through Cepheid variable stars!

Pictured: Andromeda galaxy

At the International Astronomical Union Congress held in Rome from 65438 to 0952, Budd made his discovery public, and popular magazines and newspapers reported it one after another, which stimulated the public's imagination of the universe.

1958, 65-year-old Bud ended his retirement and started a long trip to Europe before his masterpiece was published. On the other hand, swope continued to measure the light spots recorded on the negative diligently and converted them into charts and curves.

But no one expected that Bud would never come back.

1960, Budd died of postoperative complications, so his partner swope had to finish their project independently. Swope tried his best to sort out all the data with Bud's dream, and also accomplished what Bud had hoped to accomplish-to find out their respective period-luminosity relationships for Cepheid variables belonging to two star families.

From 1950s to 1970s, it was not easy for astronomers to see the rich galaxy cluster at the end of Hubble volume, which required the close cooperation of two telescopes.

With the gradual accumulation of data of distant galaxy clusters, alarm signals suddenly appear-some properties of the galaxy clusters studied have evolved over time, and the data obtained by scientists trying to use galaxies as research tools have a great deviation.

In fact, they have always ignored one of the most critical factors-celestial bodies are constantly evolving, but this evolutionary effect will have a huge impact on cosmology research, which is enough to make the highly sought-after cosmological parameters unrecognizable. Using galaxy clusters as a tool to measure the universe is a dead end. Astronomers have made many rounds of tests on a large number of data, but the photometric error is still very large.

1999, Shandage recalled his efforts to determine the geometric properties of the universe for decades, and described the finally calculated curvature parameters of the universe as "chicken ribs". Sadly, people have gradually discovered that the brightest galaxy in the cluster is actually complex and unpredictable, and Sandach's efforts to understand the universe by traditional methods have finally failed.

Have all these years of hard-working astronomical observations been in vain?

But then they realized that the powerful equipment he and his colleagues developed for the 200-inch telescope and the galaxy cluster data collected were of great value to other research.

Cosmological research no longer makes and uses galaxy clusters as research tools, but focuses on the evolution of galaxies themselves. On the contrary, it laid the foundation for a new research field-galaxy evolution.

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Explore the depths of the universe

A fascinating and adventurous journey

1On May 8, 997, George joerger, a professor of astronomy at California Institute of Technology, was observing with students through a 200-inch telescope. Radio astronomer Dale suddenly received a phone call saying that a new gamma ray burst had been discovered.

Astronomers now believe that the optical afterglow of gamma-ray bursts is synchrotron radiation emitted by electrons hovering in a magnetic field driven by shock waves. Immediately after the gamma ray burst, a long and narrow jet appeared, spewing out in the right direction. The speed of these jets is close to the speed of light. In a few seconds, they penetrate the outer layer of the star and throw the material inside the star into space.

Pictured: gamma ray burst

Dying massive stars in the galactic disk will trigger gamma-ray bursts, which gives astronomers a valuable opportunity to see the physical environment of the star-forming region-the production of metals in the universe.

As a result, astronomers turned their eyes from the light-emitting ladder to the light-absorbing material and stepped into a more far-reaching early universe. However, because the intergalactic gases are very thin, it is very difficult to detect their faint light, but it is imperative to detect them: most of the history of the evolution of the universe is preserved in the intricate and rich network structure of the universe. The cosmic web is full of primitive gas. Gases accumulate, cool and condense into stars and galaxies. The latter emits radiation, highlighting metal-rich material fragments.

Therefore, the cosmic web has dual functions-it is an inexhaustible baryon vein and a warehouse for storing radiation and metal substances.

In the 20th century, two questions have been lingering in the minds of astronomers.

The first question: Are there planets similar to Earth around other stars?

The second question: What exactly is dark matter?

After analyzing the motion speed of a single galaxy in the later cluster, Zwicky was surprised to find that the galaxies were running so fast that the cluster should have been torn apart a long time ago. But galaxy clusters seem to be safe all the time, so something must be binding the galaxies and keeping them tightly together. He considered various explanations, and finally proposed that there must be a lot of "dark matter" in the galaxy cluster, which acts as a gravitational adhesive.

Although not directly observed, zwicky concluded that there could be nothing to explain his observation except dark matter.

Many people began to speculate on what dark matter really is. Some people say it's diamonds, others say it's bricks, and some even say it's trillions of tiny black holes in the galaxy halo. But they can't come to a conclusion.

With the development of astronomical observation, the initial search for dark matter has evolved into the search for exoplanets. The search year after year has brought more and more fruitful results. In this way, new technologies release weaker and more subtle signals. This is a daily - happened thing. The research team made great strides towards a goal, but later it developed into a relay race, constantly moving towards an unexpected destination.

The exploration of the nature of "dark matter" in 1930s showed astronomers the brightest astronomical phenomenon in the universe. In this story interwoven with scientific discoveries, scientists want to find out the characteristics of dark matter (this mysterious substance keeps galaxies stable and prevents them from falling apart), so they vigorously develop observation technology in order to find dim things in bright places.

Unexpectedly, they found brown dwarfs instead of dark matter, and developed the technology of searching for exoplanets. Search for exoplanets, and finally develop the high resolution needed to find terrestrial planets.

Pictured: Brown Dwarf

This strong desire drives them to make a quick and in-depth investigation of the whole day. The increasingly perfect detection equipment, computers and data analysis tools make these surveys possible.

Through these observations, astronomers have recently discovered thousands of exoplanets and seen more and more rare astronomical phenomena. These data help astrophysicists to explore the origin of the universe.

In fact, in addition to the massive data brought by the observation of the universe itself, we also see the epitome of these astronomers' daily work: facing a completely unknown world, they stand on the channel around the dome, looking up at the stars with binoculars in the dark night and smelling the oil. In their eyes, observing at Paloma Observatory is like "a grand romantic adventure".

Step by step, they took mankind out of the solar system, out of the Milky Way, towards stars, galaxies and clusters of galaxies, and towards the deepest part of the universe.

They will face all kinds of challenges and come to a deadlock, but they still cherish the yearning for the universe. For the change of human cognition, they choose to stand alone on this "astronomical island" and open a beautiful era for human exploration of the universe. It can be said that their intelligence and courage are as fascinating as the vast universe.