Astrometry of the stellar image of U Her amplified by the circumstellar 22 GHz water masers

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英语作文对天文的解释

英语作文对天文的解释Astronomy is the study of celestial objects, such as stars, planets, comets, and galaxies. It is one of theoldest sciences and has been studied for thousands of years. Astronomy is a fascinating subject that has captured the imaginations of people for centuries. It is a science that has helped us to understand our place in the universe and has inspired us to explore the unknown.The study of astronomy can be divided into several branches, including observational astronomy, theoretical astronomy, and astrophysics. Observational astronomyinvolves the use of telescopes and other instruments to study celestial objects. Theoretical astronomy involves the development of mathematical models to explain the behaviorof these objects. Astrophysics is a branch of astronomythat focuses on the physical properties of celestial objects.One of the most important discoveries in astronomy wasmade by the Polish astronomer Nicolaus Copernicus in the 16th century. Copernicus proposed that the sun, not the Earth, was the center of the solar system. This idea was revolutionary at the time and challenged the prevailing view that the Earth was the center of the universe. Copernicus' theory was later confirmed by the observations of Galileo Galilei and others.Another important discovery in astronomy was made by the German astronomer Johannes Kepler in the 17th century. Kepler discovered that the planets move in elliptical orbits around the sun, rather than in perfect circles as had been previously thought. This discovery helped to explain the observed motions of the planets and laid the groundwork for the development of modern astronomy.The study of astronomy has also led to many practical applications. For example, astronomers use their knowledge of celestial objects to develop accurate calendars and timekeeping systems. They also use their understanding of the properties of light to develop technologies such as telescopes and cameras.In recent years, astronomy has also played a key role in the search for extraterrestrial life. Astronomers have discovered thousands of planets orbiting other stars, and are working to determine whether any of these planets could support life as we know it.In conclusion, astronomy is a fascinating subject that has contributed greatly to our understanding of the universe. From the ancient observations of the stars to the cutting-edge research of modern astronomers, this science has captured the imaginations of people for centuries. As we continue to explore the universe, we are sure to make many more exciting discoveries in the field of astronomy.。

探索月球奥秘的作文英语作文

探索月球奥秘的作文英语作文探索月球奥秘的作文英语作文在平日的学习、工作和生活里，大家总少不了接触作文吧，作文是通过文字来表达一个主题意义的记叙方法。

如何写一篇有思想、有文采的作文呢？以下是小编帮大家整理的探索月球奥秘的作文英语作文，欢迎阅读，希望大家能够喜欢。

月球又称“月亮”。

在望远镜发明之前，古代的人们只能在晴朗的夜晚，用眼睛仰望皎洁的明月。

看到月亮表面有明有暗，形状奇特，于是人们就编出如嫦娥奔月、吴刚伐桂、玉免捣药等美丽神话。

古希腊人则把月球看作美丽的狩猎女神阿尔忒弥斯，并且把女神狩猎时从不离身的银弓作为月球的天文符号。

The moon is also called the moon. Before the invention of telescope, ancient people could only look up at the bright moon with their eyes on a clear night. Seeing the moon's surface is bright and dark, and its shape is strange, people have made up Beautiful myths such as Chang'e running to the moon, Wu Gang cutting the laurel, Yu Mian tampering with medicine and so on. The ancient Greeks regarded the moon as Artemis, the beautiful hunting goddess, and regarded the silver bow that the goddess never left when hunting as the astronomical symbol of the moon.月球基本上没有水，也就没有地球上的风化、氧化和水的腐蚀过程，也没有声音的传播，到处是一片寂静的世界。

我对天文感兴趣英语作文

我对天文感兴趣英语作文I've always been fascinated by the stars and the mysteries of the universe. There's something so awe-inspiring about the vastness of space and the countless galaxies, planets, and stars that exist beyond our own.It's a constant reminder of how small we are in the grand scheme of things.Stargazing is one of my favorite pastimes. There's nothing quite like lying on a blanket and looking up at the night sky, trying to pick out constellations and marveling at the sheer number of stars that are visible on a clear night. It's a peaceful and humbling experience that never fails to leave me in awe.I love learning about the latest discoveries in astronomy. Whether it's a new exoplanet that has been found or a breakthrough in our understanding of black holes, I'm always eager to soak up as much knowledge as I can about the cosmos. It's amazing to think about how much we'velearned about the universe, and yet how much more there is still to discover.The beauty of the night sky has inspired countless works of art and literature, and it's easy to see why. There's a sense of wonder and mystery that comes with contemplating the stars, and it's no wonder that so many people have been captivated by them throughout history.It's a reminder of the power of nature to inspire and awe us.I hope to one day have the opportunity to see the stars from a different perspective perhaps by traveling to a remote location with minimal light pollution, or even by venturing into space myself. The idea of seeing the Earth from afar and experiencing weightlessness is incredibly exciting to me, and I can only imagine how profound an impact it would have on my appreciation for the cosmos.In the end, my interest in astronomy is driven by a deep-seated curiosity about the unknown. The universe is full of unanswered questions and unexplored territories,and the thought of delving into those mysteries is endlessly thrilling to me. It's a reminder that there is always more to learn and discover, and that the universe is a place of endless wonder and possibility.。

2023年北京重点校高三(上)期末英语汇编：阅读理解C篇

2023年北京重点校高三（上）期末英语汇编阅读理解C篇一、阅读理解（2023秋·北京顺义·高三统考期末）For astronomers who are sighted, the Universe is full of visual wonders. From shimmering planets to shinning galaxies(星系), the universe is impressively beautiful. But those who are visually impaired cannot share that experience. So astronomers have been developing alternative ways to convey(传递)scientific information.Recently, the journal Nature Astronomy published the latest in a series of articles on the use of sonification in astronomy. Sonification describes the change of data into digital audio(声音)files, which allows them to be heard, as well as read and seen.In August, Kimberly Arcand, a data-visualization expert and science communicator at the Center for Astrophysics and others transformed some of the first images of the black hole at the centre of the Perseus cluster from the James Webb Space Telescope into sound. They worked under the guidance of people who are blind to map the intensity and colours of light in the headline-grabbing pictures into audio. The sonification of an image of gas and dust in a distant nebula(星云), for instance, uses loud high-frequency sounds to represent bright light near the top of the image, but lower-frequency loud sounds to represent bright light near the image’s centre. The black hole sonification translates data on sound waves travelling through space-created by the black hole’s impact on the hot gas that surrounds it-into the range of human hearing.Scientists in other fields have also experimented with data sonification. Some have explored whether it can help with discovering Alzheimer’s disease from brain scans. Sound has even been used to describe ecological shifts caused by climate change in an Alaskan forest, with researchers assigning various musical instruments to different tree species.In the long run, such approaches need to be strictly evaluated to determine what they can offer that other techniques cannot. For all the technical accuracy displayed in individual projects, the Nature Astronomy series points out that there are no universally accepted standards for sonifying scientific data, and little published work that evaluates its effectiveness.1．What does the underlined word “impaired” in Paragraph 1 most probably mean?A．Appealing. B．Damaged. C．Directed. D．Impressive.2．The examples in Paragraph 4 are intended to ______.A．show the widespread use of sonificationB．introduce the common process of sonificationC．provide people with the cure for particular diseasesD．improve the application of sonification to more fields3．As for sonification, which would the author agree with?A．The use of sonification helps to analyze data effectively.B．The standardization of sonification has yet to be achieved.C．Sonification can transform some data that other techniques cannot.D．Lower-frequency sounds show bright light near the top of the image.（2023秋·北京朝阳·高三统考期末）Finland was known as a rather quiet country. Since 2008, the Country Brand Delegation (国家品牌代表团) has been looking for a national brand that would make some noise to market the country as a world-famous tourist destination. In 2010, the Delegation issued a “Country Brand Report,” which highlighted a host of marketable themes, including Finland’s famous educational system. One key theme was brand new: silence. As the report explained, modern society often seems intolerably loud and busy. “Silence is a resource,” it said.Silence first appeared in scientific research as a control or baseline, against which scientists compare the effects of noise or music. Researchers have mainly studied it by accident, as physician Luciano Bernardi did in his study of the physiological (生理学) effects of music. “We didn’t think about the effect of silence,” he said. Bernardi observed two dozen test subjects while they listened to six musical tracks. He found that the impacts of music could be read directly in the bloodstream, via changes in blood pressure, carbon dioxide, and circulation in the brain. “During almost all sorts of music, there was a physiological change with a condition of arousal (兴奋),” he explained.This effect made sense, given that active listening requires attention. But the more striking finding appeared between musical tracks. Bernardi and his colleagues discovered that randomly added stretches of silence also had a great effect, but in the opposite direction. In fact, two-minute silent pauses proved far more relaxing than either “relaxing” music or a longer silence played before the experiment started. The blank pauses that Bernardi had considered irrelevant, in other words, became the most interesting object of study. Silence seemed to be heightened by contrasts, maybe because it gave test subjects a release from careful attention. “Perhaps the arousal is something that concentrates the mind in one direction, so that when there is nothing more arousing, then you have deeper relaxation,” he said.This finding is reinforced by neurological (神经系统的) research. Relevant research shows when our brains rest quietly, they integrate external and internal information into “a conscious (意识的) workspace.” Freedom from noise and goal-directed tasks, it appears, unites the quiet without and within, allowing our conscious workspace to do its thing to discover where we fit in.Noora Vikman, a consultant on silence for Finland’s marketers, knows silence well. Living in a remote and quiet place in Finland, she discovers thoughts and feelings that aren’t detectable in her busy daily life. “If you want to know yourself, you have to be with yourself, and discuss with yourself, and be able to talk with yourself.” 4．Why does the author mention the Country Brand Report in Paragraph 1?A．To present how Finland viewed silence.B．To highlight the need of noise in Finland.C．To explain why Finland issued the brands.D．To indicate the authority of the Delegation.5．What can be inferred about Luciano Bernardi’s discovery?A．It challenged the calming effect of music.B．It emphasized the role of silence between sounds.C．It illustrated the loss of attentiveness after silence.D．It stated brains’ information processing in the quiet.6．As for Noora Vikman’s attitude to silence, the author is ________.A．doubtful B．supportive C．disapproving D．unconcerned7．Which would be the best title for the passage?A．Silence: A Limited Resource B．Silence: A Misunderstood ToolC．Silence: The Unexpected Power D．Silence: The Value by Contrasts（2023秋·北京通州·高三统考期末）NASA’s spacecraft Dart hit an asteroid (小行星) 11.3 million kilometers away at a speed, changing the asteroid’s orbit and lowered its cycle period by I5 minutes, the space organization announced on Monday.Some said the move shows the world might now be able to prevent asteroids — the kind that made the dinosaurs extinct — from hitting the Earth. The asteroid that was controlled belonged to a double-asteroid system. It had a 160-meter diameter while the other asteroid’s diameter is over 500 meters. The bigger asteroid can be compared to the one that ended the dinosaur era 67 million years ago. A hit from an asteroid that size can cause unimaginable destruction.However, it is too early to assert that the world has gained the ability to prevent asteroids from hitting us. The asteroid that was controlled was only 160 meters in size. Its cycle period was changed, without changing its orbit significantly. It is still not clear if the orbit of a much larger asteroid headed toward the Earth can be changed successfully.In brief, NASA’s success in changing the course of a harmful asteroid is definitely praiseworthy, but much more needs to be done before we can say the world’s security from some unpredictable asteroid is guaranteed.It should be noted that changing the orbit of an asteroid involves more than just sending an object into space and commanding it to hit the asteroid. While it is hard enough to hit an asteroid, it is even more difficult to lock onto one in the first place. It means having the ability to observe approaching asteroids, measuring their respective speeds, and deciding which ones might pose a danger to the Earth.Therefore, there’s more to Dart hitting the asteroid than meets the eye. And these are key areas where global scientists need to work harder in the future.8．What was the latest news about NASA?A．Its new program failed.B．Its manned spaceship hit an asteroid.C．Its spacecraft changed an asteroid’s orbit.D．Its spacecraft saved the earth from being destroyed.9．What does the underlined word “assert” in Paragraph 3 most probably mean?A．Advise. B．State. C．Promise. D．Admit.10．What can we learn about the asteroid that was hit?A．It was comparatively small in size.B．Its orbit was changed significantly.C．It travelled at a higher speed than before.D．It was powerful enough to end dinosaur era.11．What is the author’s attitude toward using spacecrafts to change the asteroids orbits?A．Neutral. B．Optimistic.C．Pessimistic. D．Not mentioned.（2023秋·北京房山·高三统考期末）With the development of technology, “paperless” seems to be the new trend. Instead of writing by hand, people began to use computers to type in order to produce text quickly. Some people said word processing made producing and editing text much easier. Will handwriting be completely replaced by typing?A 2017 study in the journal Frontiers in Psychology found that regions of the brain associated with learning were more active when subjects completed a task by hand instead of on a keyboard. Not only that, but the study’s authors also found that writing by hand could promote “deep encoding or processing” in a way that typing does not.In fact, there have been many such studies to arrive at that conclusion. One notable example from 2014 compared students who took notes by hand with those who took notes on laptops. They found that the students using laptops tended to write down what the professor said word for word, while those who took notes by hand were more likely to listen to what was being said, analyzing it for important content and “processing information and reframing it in their own words.” When asked conceptual questions about the lecture, students who had taken notes by hand were better able to answer than those who had typed their notes.Daniel Oppenheimer, one of the study’s co-authors, told Medium’s Elemental that in order to analyze the lecture, people had to contemplate the material and actually understand the arguments. This helped them learn the material better. The most annoying thing about writing by hand is also what makes it so effective for learning.Virginia Berninger, a professor at the University of Washington, says, “When we write a letter of the alphabet, the process of production involves pathways in the brain that go near or through parts that manage emotion.” Pressing a key doesn’t stimulate those pathways the same way. She says, “It’s possible that there’s not the same connection to the emotional part of the brain when people type, as opposed to writing in longhand.” “In the same vein, writing in longhand also allows people to really figure out what they mean to say,” Oppenheimer says, “which may help self-expression.”Our keyboards are great for a lot of things. But sometimes, there’s no replacing the feeling of spreading out a clean sheet of paper, uncapping a beloved pen, and letting the ink flow.12．The author uses the question underlined in Paragraph 1 to ________.A．predict the ending B．introduce the topicC．emphasize an opinion D．draw a conclusion13．What can be inferred from the passage?A．People who write by hand tend to think deeply.B．People who write by hand are likely to make comparisons.C．People who write by hand slow down their learning process.D．People who write by hand find it difficult to improve their memory.14．As for handwriting, the author thinks it is ________.A．accurate B．unimportant C．annoying D．beneficial（2023秋·北京丰台·高三统考期末）Over millions of years humans have responded to certain situationswithout thinking too hard. If our ancestors spotted movement in the nearby forest, they would run first and question later. At the same time, the ability to analyze and to plan is part of what separates us from other animals. The question of when to trust your instinct (直觉)and when to think slow matters in the office as much as in the savannah(草原).Slow thinking is the feature of a well-managed workplace. Yet instinct also has its place. Some decisions are more connected to emotional responses and less to analysis. In demanding customer-service or public-facing situations, instinct is often a better guide to how to behave.Instinct can also be improved. Plenty of research has shown that instinct becomes more unerring with experience. In one well-known experiment, volunteers were asked to assess whether a selection of designer handbags were real or not. Some were instructed to operate on instinct and others to deliberate(深思熟虑)over their decision. Instinct worked better for those who owned at least three designer handbags; indeed, it outperformed analysis. The more expert you become, the better your instinct tends to be.However, the real reason to embrace fast thinking is that it is, well, fast. It is often the only way to get through the day. To take one example, when your inbox floods with new emails at the start of a new day, there is absolutely no way to read them all carefully. Instinct is what helps you decide which ones to answer and which to delete or leave unopened. Fast thinking can also help the entire organization. The value of many managerial decisions lies in the simple fact that they have been made at all. Yet as data explodes, the temptation(诱惑)to ask for one more bit of analysis has become much harder to resist. Managers often suffer from overthinking, turning a simple problem into a complex one.When to use instinct in the workplace rests on its own form of pattern recognition. Does the decision maker have real expertise in this area? Is this a field in which emotion matters more than reasoning? Above all, is it worth delaying the decision? Slow thinking is needed to get the big calls right. But fast thinking is the way to stop deliberation turning to a waste of time.15．What does the underlined word “unerring” in Paragraph 3 probably mean?A．Accurate. B．Creative. C．Controllable. D．Obvious.16．What can we learn from the passage?A．Managers can afford the cost of slow thinking.B．Fast thinking can be a boost to work efficiency.C．Slow thinking will hold us back in the long run.D．Too much data is to blame for wrong decisions.17．What is the author's purpose of writing the passage?A．To explain how instinct works.B．To compare instinct and slow thinking.C．To highlight the value of instinct in the workplace.D．To illustrate the development of different thinking patterns.（2023秋·北京海淀·高三统考期末）A new study has found human feelings can accurately be expressed numerically and have more predictive power for how we behave than formal studies of socioeconomic factors like household income and employment status.The study co-author Andrew Oswald, a professor of economics and behavioral science gathered informationfrom nearly 700,000 people, who were asked annually over a three-decade period how they felt on a numerical scale about their job, spouse, health and home. Using the data collected, researchers constructed statistical models to show how people felt and the actions they took as a result of their reported feelings. The study found that ratings of life satisfaction had a direct linear (线性的) relationship to actions people subsequently take. Participants who rated their job satisfaction as a 2 out of 7 had a 25% probability of quitting their job. Those who rated a 6 out of 7 had only a 10 percent probability of quitting. The same was true across other measures like marriage, health and housing.Previous research has also shown data about feelings predict human outcomes, but not in such a linear fashion; the degree of satisfaction served as a good predictor of future actions. Additionally, economists have previously been critical of feelings data because they considered them unscientific and unreliable. But this study shows socioeconomic factors have a lesser probability of predicting human behavior than data on feelings.Though the study shows numbers can quantify feelings, researchers are still a bit confused as to why estimates of seemingly subjective feelings can be such good predictors of future actions. According to Oswald, a number of factors could be at play. Humans are very experienced in comparative thinking and are able to scale their own life satisfaction against that of their neighbors. We’re also accustomed to using measuring devices for other aspects of life like temperature, distance and weight, so it shouldn’t be too surprising that we’re able to measure our feelings in a similarly accurate way. Another study co-author Caspar Kaiser says that it may also be because we communicate our feelings and do it in a scaled fashion every day. This could be why it comes out in the data more accurately than in objective markers.Ori Heffetz, an economics professor who was not involved in the study, says that this research shows feelings data shouldn’t be underestimated even if they’re more difficult to study. “Scientists who ignore this do so at their own risk,” he says.Looking ahead, Kaiser hopes this same data can be studied in lower-income countries so that it can be applied universally to places with varied levels of economic development. But more than anything else he’s interested in studying why feelings work so well.18．Paragraph 2 is mainly about .A．research process and findingsB．research topic and significanceC．research subjects and purposeD．research data collection and analysis19．What can we know about the study?A．It also applies to people from lower-income countries.B．It challenges the opinion that feelings data are unreliable.C．It explains why ratings of feelings can foresee future actions.D．It first shows data about feelings can predict human behavior20．What is Ori’s attitude towards the study?A．Neutral. B．Skeptical. C．Supportive. D．Cautious.21．Which would be the best title for the passage?A．How You Rate Your Life Predicts Your Future BehaviorB．Feelings Forecast Actions Better than Economic FactorsC．Why Your Feelings Affect Your Future ActionsD．Ranking Every Aspect of Your Life Counts（2023秋·北京西城·高三统考期末）Of the more than 3,000 species of mosquitoes in the world, just a small number specialize in sucking human blood. How mosquitoes track us down so effectively isn’t currently known, but it matters, since they carry dangerous diseases which may cause death.“In fact, stopping these annoying insects in their tracks could save up to half a million lives lost to those diseases each year,” said Carolyn Gauff, a professor of ecology and evolutionary biology at the Princeton Neuroscience Institute. That’s why Gauff’s team wants to understand how they find and target humans.Mosquitoes mostly choose what to bite based on odor (气味). Knowing how a potentially disease-carrying mosquito finds a person, while ignoring other warm-blooded animals, is a key question. But it’s not easy to answer, since any animal smell is made up of hundreds of chemicals mixed together in specific percentage. “The actual chemicals that are found in human odor are basically the same as the chemicals found in animal odor—it’s the percentages and the relative large amount of those substances in human mixtures that’s unique,” said Gauff.To investigate, researchers decided to record neural activity in the brain of mosquitoes while exposing them to natural human and animal odor samples. They collected odor samples from about 40 different animals. When they compared some of those with the 16 human samples, something jumped out. Decanal is particularly rich in human skin. Common in the natural world, in humans, decanal comes from another, more complex substance. When one component of our skin’s natural oils, sapienic acid, breaks down, decanal is left over. This acid is only found in human beings. It’s what likely leads to the high levels of decanal that help the mosquitoes smell their way to us.Understanding what the mosquitoes are targeting is only part of the story; knowing how they do it is also important. To see exactly how mosquitoes use this sense, scientists used genetically modified (转基因的) mosquitoes so that they could cut open mosquitoes’ heads and watch neurons firing when they’re exposed to human and animal odors. The research team already knew that mosquitoes have about 60 different types of neurons that sense odors, so when they looked in the insects’ brains, they thought they might see a lot of activity. But it was surprisingly quiet, meaning that the signal was perhaps quite simple, down to just a couple types of neurons. “One type of neuron responded really strongly to both humans and animals. Another type of neuron responded to both—but it responded much more strongly to humans than animals,” Gauff said.How to keep mosquitoes’ decanal signal from being transmitted will be the research team’s next focus. Gauff hoped their current work could be used to make mosquito killers and attractants to prevent disease. 22．What’s the final purpose of the research conducted by Gauff’s team?A．To study why only certain mosquitoes suck human blood.B．To investigate the neural activity in mosquitoes’ brains.C．To help prevent deadly diseases caused by mosquitoes.D．To test the effectiveness of mosquito killers.23．To which substance(s) would mosquitoes mostly be attracted?A．Natural oil from human skin.B．Chemicals in the environment.C．Decanal generated in human blood.D．Remains of decomposed sapienic acid.24．What can we learn from the passage?A．Most mosquito neurons are not involved in responding to human odor.B．Genetically modified mosquitoes are not sensitive to human odor.C．Further research will focus on odor signal and neural connection.D．Chemicals found in human and animal odors are quite different.（2023秋·北京东城·高三统考期末）Every robot is trained in some way to do a task. By seeing what to do, robots can copy the way of doing the task. But they do so unthinkingly, perhaps relying on sensors to try to reduce collision (碰撞) risks, rather than having any understanding of why they are performing the task or where they are within physical space. It means they will often make mistakes—hitting the object in their way, for instance.Hod Lipson and his colleagues are trying to face the challenge. They placed a robot arm in a laboratory where it was surrounded by four cameras at ground level and one camera above it. These fed video images back to a deep neural(神经的) network, a form of AI, connected to the robot that monitored its movement within the space. For 3 hours, the robot arm moved randomly and the neural network was fed information about the arm' s mechanical inputs and watched how it responded by seeing where it moved to in the space. This generated nearly 8,000 data points—and the team generated an additional 10,000 through a simulation (模拟) of the robot in a virtual version of its environment.To test how well the AI had worked, a cloud-like diagram was generated to show where the neural network “thought” the arm should be found as it moved. It was accurate to within 1 percent, meaning if the workspace was 1 metre wide, the system correctly estimated its position to within 1 centimetre. If the neural network is considered to be part of the robot itself, this suggests the robot has the ability to visualise where it physically is at any given moment.“To me, this is the first time in the history of robotics that a robot has been able to create a mental model of itself,” says Lipson. “It’s a small step, but it’s a sign of things to come.”Learning about the research, Andrew Hundt at the Georgia Institute of Technology says, “There is potential for further research to lead to useful applications based on this method, but not self- perception. The computer simply matches shape and motion patterns that happen to be in the shape of a robot arm that moves.” David Cameron at the University of Sheffield, UK, also says that following a specified path to complete a goal is easily achieved by existing robots.25．Hod Lipson’s work focuses on robots .A．flexibility B．self-awarenessC．deep-learning ability D．error correction26．What is the function of the neural network in the experiment?A．To process and transform neural information.B．To study and simulate AI’s virtual environment.C．To analyse and predict the arm’s position changes.D．To record and output the video images of the robot.27．As for the result of the experiment, Andrew Hundt is .A．sympathetic B．contentC．uncertain D．disapproving 28．What is the main purpose of the passage?A．To discuss a scientific concept.B．To assess a scientific finding.C．To introduce a science application.D．To present a science research.参考答案1．B 2．A 3．B【导语】本文是一篇说明文。

以天文摄影展为题的英语作文高中

以天文摄影展为题的英语作文高中Astronomy Photography ExhibitionIntroductionAstronomy photography is a fascinating and beautiful form of art that captures the wonders of the universe through the lens of a camera. From stunning images of the night sky to detailed pictures of distant galaxies, astronomy photography allows us to glimpse the beauty and complexity of the cosmos. In this essay, we will explore the world of astronomy photography through the lens of a photography exhibition.The ExhibitionThe astronomy photography exhibition is a showcase of the best and most breathtaking images of the universe captured by talented photographers from around the world. The exhibition features a wide range of photographs, including images of the moon, planets, stars, nebulae, and galaxies. Each photograph is a work of art in its own right, showcasing the beauty and wonder of the cosmos.The exhibition is divided into several sections, each focusing on a different aspect of astronomy photography. The first section features images of the moon, taken from both Earth andspace. These images capture the moon in all its phases, from the familiar bright full moon to the eerie darkness of a new moon. The detail and clarity of these images are truly stunning, revealing the rugged terrain and craters of the moon in exquisite detail.The next section of the exhibition focuses on the planets of our solar system. Photographs of Jupiter show its swirling clouds and massive Great Red Spot, while images of Saturn capture its iconic rings in all their glory. Images of Mars reveal the planet's rusty red surface and polar ice caps, while photographs of Venus showcase its thick cloud cover and intense heat.Moving beyond our solar system, the exhibition features images of distant stars and nebulae. Photographs of the Orion Nebula show its colorful clouds of gas and dust, while images of the Pleiades star cluster reveal its sparkling blue stars. Stunning images of the Andromeda Galaxy showcase its spiral arms and billions of stars, while pictures of the Milky Way galaxy capture our own home in the universe.The photographersThe photographers featured in the exhibition are a diverse group of talented individuals from around the world. Some are professional astronomers who use sophisticated telescopes andcameras to capture images of the cosmos, while others are amateur photographers who simply have a passion for astronomy and a keen eye for capturing the beauty of the night sky.One such photographer is Sarah Johnson, a professional astronomer who uses a powerful telescope at an observatory in Chile to capture stunning images of distant galaxies. Sarah's photographs of the Andromeda Galaxy are among the most detailed and beautiful images in the exhibition, showcasing the galaxy's spiral arms and billions of stars in exquisite detail.Another photographer featured in the exhibition is Mark Davis, an amateur astronomer who takes breathtaking images of the moon and planets from his backyard observatory. Mark's images of Jupiter and Saturn are some of the clearest and most detailed images ever captured by an amateur photographer, showcasing the beauty and wonder of our solar system.The impactThe astronomy photography exhibition has had a profound impact on those who have had the opportunity to view it. Visitors to the exhibition are often awestruck by the beauty and complexity of the images on display, gaining a newfound appreciation for the wonders of the universe. Many are inspiredto take up astronomy photography themselves, purchasing telescopes and cameras to capture their own images of the night sky.The exhibition has also raised awareness of the importance of astronomy and space exploration, highlighting the beauty and scientific value of studying the cosmos. By showcasing the beauty of the universe through the art of photography, the exhibition has inspired a new generation of astronomers and space enthusiasts to explore the wonders of the cosmos.ConclusionIn conclusion, the astronomy photography exhibition is a showcase of the beauty and wonder of the universe captured through the lens of a camera. From stunning images of the moon and planets to detailed pictures of distant galaxies, astronomy photography allows us to glimpse the beauty and complexity of the cosmos in ways that are both inspiring and breathtaking. Through the work of talented photographers from around the world, the exhibition showcases the beauty and wonder of the universe in all its glory.。

研究太空物体的科学家的英文单词

研究太空物体的科学家的英文单词一、背景介绍在当今世界，太空探索和研究已经成为各国科技发展的重要领域。

随着人类对宇宙的认知不断深入，越来越多的科学家投身于太空物体的研究工作。

他们致力于探索太阳系、星系及宇宙其他角落的奥秘，为人类认识宇宙、探索外太空提供了重要的科学数据和支撑。

在英语中，有一些专门用来形容研究太空物体的科学家的专业术语，下面将为大家详细介绍这些英文单词。

二、研究太空物体的科学家的英文单词1. AstronomerAstronomer是指从事天文学研究的科学家，他们主要研究宇宙中的天体、宇宙射线等现象。

2. AstrophysicistAstrophysicist是指研究宇宙物理现象的科学家，他们将物理学理论与天文学现象相结合，探索宇宙的物质和运动规律。

3. CosmologistCosmologist是指研究宇宙起源和结构的科学家，他们探索宇宙的演化历史和宇宙学理论，试图解答宇宙的起源和未来命运。

4. Planetary ScientistPlanetary Scientist是指研究行星和其他太阳系天体的科学家，他们主要关注行星地质、大气、磁场等特征，以及行星形成和演化过程。

5. Space PhysicistSpace Physicist是指研究太空和近地空间物理现象的科学家，他们研究太阳风、地球磁层、行星磁场等现象，探索宇宙与地球的相互作用。

三、研究太空物体的科学家的贡献研究太空物体的科学家通过不懈的努力，取得了许多重要的科学成果，为人类认识宇宙、探索太空提供了重要的支撑。

他们为我们了解宇宙的起源、宇宙中的物质和能量分布、行星和星系的形成过程以及宇宙规律等方面做出了重要贡献。

他们的研究还促进了科技领域的发展，为人类的实际生活和工业生产带来了许多创新。

太空科学家的研究成果为太空探索任务的设计和执行提供了关键的科学数据和技术支持，为人类的太空探险之路打开了新的可能性。

四、结语研究太空物体的科学家是推动太空探索与研究的中坚力量，他们的努力使人类可以更深入地认识宇宙，探索未知的领域。

天体物理学家英文

天体物理学家英文Astronomers are the intrepid explorers of the cosmos, delving into the mysteries of the universe with unwavering curiosity and scientific rigor. These dedicated individuals, known as astrophysicists, have dedicated their lives to unraveling the secrets of the celestial bodies that populate the vast expanse of the heavens.At the heart of an astrophysicist's work lies a deep fascination with the fundamental laws that govern the behavior of stars, galaxies, and the entire cosmic landscape. From the birth and evolution of stars to the nature of black holes and the origins of the universe itself, these scientists seek to uncover the underlying principles that shape the grand cosmic tapestry.One of the primary focuses of astrophysicists is the study of the formation and evolution of stars. By analyzing the spectral signatures and luminosities of these celestial beacons, they can piece together the intricate processes that govern a star's life cycle, from its fiery birth in clouds of gas and dust to its eventual demise, whether in a supernova explosion or a gradual fading into a dense remnant like a white dwarf or neutron star.This knowledge not only satisfies our innate curiosity about the cosmos but also has profound implications for our understanding of the universe and our place within it. The elements that make up our own planet and the very molecules that form the building blocks of life were forged in the nuclear furnaces of stars, and astrophysicists play a crucial role in tracing the origins of these essential materials.Beyond the study of individual stars, astrophysicists also delve into the complex dynamics of galaxies, both near and far. By observing the intricate patterns of motion and the distribution of matter within these vast stellar systems, they can uncover the hidden forces that shape the cosmic landscape, from the gravitational pull of dark matter to the influence of supermassive black holes at the centers of many galaxies.One of the most exciting frontiers in astrophysics is the search for exoplanets – planets orbiting stars other than our own Sun. By employing sophisticated techniques like the transit method and direct imaging, astrophysicists have discovered thousands of these distant worlds, opening up new avenues for understanding the diversity of planetary systems and the potential for extraterrestrial life.The quest to unravel the mysteries of the universe is not without its challenges, however. Astrophysicists must grapple with the vastscales and extreme conditions that characterize the cosmos, often relying on cutting-edge technologies and complex mathematical models to make sense of the data they collect. From the construction of powerful telescopes and space-based observatories to the development of sophisticated computer simulations, these scientists are constantly pushing the boundaries of what is possible in the pursuit of scientific knowledge.Yet, despite the inherent difficulties of their work, astrophysicists remain driven by a profound sense of wonder and a deep commitment to expanding the frontiers of human understanding. They are the modern-day explorers, charting the uncharted realms of the universe and inspiring generations of young minds to follow in their footsteps.As we continue to delve deeper into the cosmos, the role of the astrophysicist becomes ever more crucial. These dedicated individuals not only contribute to our scientific understanding but also shape our very conception of our place in the grand scheme of the universe. Their work not only satisfies our innate curiosity but also has the potential to unlock the secrets of our origins and the future of our existence.In the end, the pursuit of astrophysics is a testament to the human spirit – a relentless drive to explore, to understand, and to push theboundaries of what is known. It is a journey of discovery that continues to captivate and inspire, and astrophysicists are the intrepid trailblazers leading the way.。

天文物理学家的英文

天文物理学家的英文English:"Astronomers are scientists who study celestial objects such as stars, planets, galaxies, and the universe as a whole. They employ a combination of observational and theoretical methods to understand the physical properties, formation, evolution, and behavior of these objects. Observational astronomers use telescopes and other instruments to collect data from distant objects, while theoretical astronomers develop mathematical models and simulations to interpret these observations and make predictions about the nature of the universe. Their research encompasses a wide range of topics, including the structure and dynamics of galaxies, the birth and death of stars, the nature of dark matter and dark energy, the origin of the universe, and the possibility of extraterrestrial life. Astronomers often collaborate with physicists, mathematicians, engineers, and computer scientists to advance our understanding of the cosmos. In addition to conducting research, astronomers also engage in education and outreach activities to share their knowledge and enthusiasm for astronomy with the public and inspire the next generation of scientists."中文翻译:"天文学家是研究天体物体如星星、行星、星系以及整个宇宙的科学家。

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a r X i v :a s t r o -p h /0208198v 1 9 A u g 2002Astronomy &Astrophysics manuscript no.February 2,2008(DOI:will be inserted by hand later)Astrometry of the stellar image of U Her ampliﬁed by thecircumstellar 22GHz water masersW.H.T.Vlemmings 1,H.J.van Langevelde 2,and P.J.Diamond 31Sterrewacht Leiden,Postbus 9513,2300RA Leiden,the Netherlands 2Joint Institute for VLBI in Europe,Postbus 2,7990AA Dwingeloo3Jodrell Bank Observatory,University of Manchester,Macclesﬁeld,Cheshire,SK119DL,EnglandReceived ;acceptedAbstract.The 22GHz H 2O masers in the circumstellar envelope of the Mira variable star U Her have been observed with MERLIN using a phase referencing technique to determine accurate astrometric positions.The positions were compared with the optical positions obtained with the Hipparcos satellite to an accuracy of 18mas.The absolute radio position of the brightest H 2O maser spot is found to match the optical position,indicating that this spot is the stellar image ampliﬁed by the maser screen in front of it.The occurrence of an ampliﬁed image in the 22GHz maser can be used to accurately determine the positions of the H 2O with respect to the star as well as with respect to the SiO and OH masers.Our observations seem to indicate that the star is not in the centre of the distribution of maser spots,which has been interpreted as a ring.Key words.masers –stars:circumstellar matter –stars:individual (U Her)–stars:AGB and post-AGB –techniques:interferometric –astrometry1.IntroductionThe circumstellar envelopes (CSEs)around late-type stars contain several maser species that are excellent probes of the dynamics of the outﬂowing material.Astrometric ob-servations are an important tool to study the locations and motions of the circumstellar masers with respect to the central star.This understanding is essential to reach the main goal of maser astrometry,which is to determine the distances to heavily enshrouded stars,that are too faint for their parallax to be determined directly.1.1.Circumstellar H 2O masersInterferometric observations of the 22GHz H 2O masers in the CSEs of Mira-variable stars with MERLIN,the VLA and Very Long Baseline Interferometry (VLBI)indicate that the H 2O masers are found up to a few hundred AU from the star (ne et al.1987).This is generally in-side the OH maser shell,which is located at up to several 1000AU.The H 2O masers often show an a-spherical dis-tribution,and the size of the maser region is thought to increase with mass-loss rate (Cooke &Elitzur 1985).The maser is expected to be pumped due to collisions (Neufeld &Melnick 1991).The 22GHz maser can then be easily ex-cited in the inner parts of the CSE at temperatures of 4002W.H.T.Vlemmings et al.:Astrometry of the U Her water masers1.2.Ampliﬁed Stellar ImageInterferometric observations of OH masers have revealed that the most compact features were only found at the blue-shifted side of the spectrum(Norris et al.1984).It was argued that this was due to ampliﬁcation of the con-tinuum maser emission from the underlying star by the maser screen in front of it.This is called the Ampliﬁed Stellar Image Theory.Ampliﬁcation of the stellar emis-sion results in a high brightness maser spot at the most blue-shifted side of the OH maser spectrum.This spot should coincide at the diﬀerent OH maser transitions,and is expected to be persistent over a long period of time. Several observations have conﬁrmed this hypothesis(e.g. Sivagnanam et al.1990).According to the ampliﬁed stellar image theory,the compact,most blue-shifted,spot is necessarilyﬁxed to the stellar position.Therefore,high resolution astromet-ric observations of this spot can be used to determine the stellar trajectory.This hypothesis has been tested for the Mira-variable star U Her by van Langevelde et al.(2000, hereafter vL00).The absolute positions of the OH maser spots were determined with respect to the radio-reference frame using extra-galactic phase reference sources.The positions were compared with the optical Hipparcos posi-tions with unprecedented accuracy.It was shown that the most blue-shifted spot was indeed located in front of the stellar radio-photosphere.The size of this spot was found to be≈20mas,which is comparable with the expected size of the radio-photosphere,which is thought to be twice the size of the star,as proposed by Reid&Menten(1997).Although the H2O masers generally show a great num-ber of spots over an area of several hundred mas,it has been argued that in some cases one of the H2O maser spots corresponds to the stellar image(Reid&Menten1990; Marvel1996;Colomer et al.2000).However,because the distribution of the H2O masers is considerably less spher-ical than that of the OH masers,it is not straightforward to assume that the stellar image underlies the most blue-shifted spot.Also,because the maser brightness depends strongly on local eﬀects such as density or pumping in-homogeneities,several bright spots can be observed and an H2O maser stellar image could be less conspicuous or persistent than the OH stellar image.Here we present phase referencing observations of the H2O masers around U Her used to determine accurate maser spot positions.These have been compared with the Hipparcos optical position and the positions obtained for the OH masers in vL00.2.ObservationsMERLIN was used to determine the positions of the H2O masers in the CSE of U Her with respect to3extragalac-tic reference sources.From the observations,which were performed on May202001,we were able to determine ac-curate astrometric positions.The observations required a total of8hours on the target source and the calibrator and reference sources.As a result the beam size was≈30×25 mas.One of the main problems of using the phase refer-encing method to determine accurate positions at22GHz is the lack of bright reference sources at that frequency. For this project3reference sources were selected from the VLBI calibrator catalog(Beasley et al.,2002).These were J1628+214(now J1630+231,≈80mJy,at2.8◦from U Her),J1635+1831(≈50mJy,at2.4◦)and J1619+2247 (≈200mJy,at4.2◦).They were selected to have aﬂat spectrum,making it possible to detect them at22GHz with a2minute integration time.Our phase reference ob-servation cycle consisted of2minutes per reference source and4minutes on the target source.The H2O masers were observed in a4MHz band with128spectral channels,pro-viding a velocity resolution of0.42km/s.The continuum reference sources were observed in a16MHz band with16 channel,giving a13.5km/s resolution.In the2minute in-tegration time on the reference source we typically reached a SNR≈5.Reference source J1628+214was also used in vL00 to determine the positions of the1667MHz OH masers around U Her.We can thus determine the positions of the H2O masers with respect to the OH masers.The positional accuracy of the reference sources with respect to the radio reference frame is≈3mas.However,as the positions were determined at2.4and8.4GHz the position at the diﬀer-ent frequencies can be diﬀerent at the sub-milliarcsecond level,as shown in e.g.Fey et al.(1997).After initialﬂux calibration with the MERLIN soft-ware,the data were processed in AIPS.Because the ref-erence sources at22GHz are weak,we performed both a normal and a reverse phase referencing scheme.In the reverse scheme,we were able to determine accurate posi-tions of both J1619+2247and J1628+214with respect to the brightest H2O maser feature of U Her.As a consis-tency check,we managed to get a good phase connection from J1628+214,the closest reference source,to the U Her H2O masers with the normal phase referencing scheme. J1635+1831was too faint for us to obtain a good phase connection.The accuracy of the phase referencing model depends on the MERLIN correlator model.The two largest uncer-tainties in the model are the telescope positions(accurate to∼5cm)and tropospheric eﬀects.Under normal cir-cumstances these combine to produce an error in absolute position measurements of up to∼10mas for a target-reference source separation of∼3◦(e.g.Kovalevsky et al 1997).3.ResultsAt the time of our observations the spectrum of the22 GHz H2O masers around U Her did not show signiﬁcant structure,as only a few features were detected.The aver-aged cross power spectrum is shown in an inlay in Fig.1. Weﬁnd that the shape of the spectrum is similar to pre-vious observations,performed with MERLIN,the VeryW.H.T.Vlemmings et al.:Astrometry of the U Her water masers3Center at RA 16 25 47.468 DEC 18 53 32.849Peak flux = 1.9579E+06 JY/B*HZ Levs = 1.958E+05 * (1, 3, 5, 7, 9)M i l l i A R C S E CMilliARC SECFig.1.The location of the U Her H 2O masers with respect to the stellar positions determined from the Hipparcos observations,as determined from phase referencing to J1628+214.The star is denoted by two circles indicat-ing the star itself and the stellar radio photo-sphere.The large cross indicates the position of the H 2O maser,the error bars are due to the positional ﬁtting.The errors on the stellar position (small cross)are due to the link to the radio-reference frame and due to the errors in the proper motion used to transpose the optical position.The triangle denotes the stellar position when using the phase referenc-ing results on the J1619+2247reference source.The inlay is the averaged cross-power spectrum of the H 2O maser emission.The masers were mapped over the velocity range indicated in the spectrum.Large Array (VLA)and with the 100-m radio telescope in Eﬀelsberg (Baines et al.in preparation;Yates &Cohen 1994;Colomer et al.2000;Engels et al.1988).In our spectrum we ﬁnd that the strongest feature is located at −15.7km/s,and this is the feature which was used to determine the phase solutions.The stellar velocity of U Her is −14.5±0.5km/s,which was determined from OH and SiO maser observations (Chapman et al.1994).As the U Her H 2O maser emission is located between −13and −20km/s,the strongest feature is not the most blue-shifted feature.After phase referencing and determining the position of J1628+214with respect to the brightest H 2O maser fea-ture of U Her,we ﬁnd that the position of J1628+214is shifted by +83mas in right ascension and +15mas in dec-lination with respect to the positions in vL00((α,δ)2000=16h 30m 11s .23117,+21◦31′34′′.3144).A similar process for J1619+2247results in a position shift of +76mas in right ascension and +25mas in declination with respect to theposition in the VLBA calibrator list.As a consistency check we have also determined the position shift of the brightest maser spot after phase referencing with respect to J1628+214.We ﬁnd that the maser spot is shifted −83and −11mas in right ascension and declination respec-tively with respect to the a priori assumed target coordi-nates.The formal uncertainty in ﬁtting a Gaussian proﬁle to the reference source or maser spot is a fraction of the beam width,and depends on the SNR of the image.For the ref-erence sources the formal position errors are of the order of 5mas in each coordinate,for the U Her maser spot the errors are ≈1mas.The best phase connection was made when phase referencing J1628+214to the brightest maser spot,so we assume that the positions as determined with J1628+214are the most reliable.The actual phase referencing errors can be estimated from the diﬀerence between the position of the brightest maser spot with re-spect to the two reference sources.From this,we conclude that our positions are accurate to within 10mas,which is in agreement with the estimated errors due to the cor-relator model that are described above.For the brightest H 2O maser spot around U Her we then ﬁnd a position of (α,δ)2000=16h 25m 47s .468,+18◦53′32′′.849at the time of our observations.To compare this position to the stellar position of U Her we have extrapolated the optical position found by the Hipparcos satellite at J1991.25to our epoch of ob-servation.We have used the proper motion and parallax determined by monitoring the position of the most blue-shifted OH maser spot,which was shown to be the stellar image.The ﬁrst ﬁt was performed in vL00for 6epochs of observations,a ﬁt including additional epochs was pre-sented in Vlemmings et al.(2000).As described in vL00,the OH maser proper motion is entirely consistent with the Hipparcos proper motion.The error in the transposed position is dominated by the error in proper motion.At our epoch of observation this error is ≈6mas in each bined with the errors on the parallax and our position errors,we have been able to compare the radio and optical position with ≈18mas accuracy.Fig.1shows a map of the H 2O maser features,covering the velocity range indicated in the spectrum,including the position of the star.Circles indicate the size of the star and the radio-photosphere.The size of the radio-photosphere can be estimated from SiO maser observations by Diamond et al.(1994).Their observations provide an upper limit of ≈20mas if,as proposed by Reid &Menten (1997),the radio-photosphere extends to the edge of the SiO masing region.The triangle denotes the stellar position as deter-mined when using the maser positions with J1635+1831as the reference source.Although the size of the brightest H 2O maser spot (≈50mas)is larger than the expected size of the stel-lar radio-photosphere,most likely due to the blending of several weaker maser features,the position of peak inten-sity matches the predicted location of the star within the errors.This indicates that the H 2O maser spot also co-4W.H.T.Vlemmings et al.:Astrometry of the U Her water masersincides with the most blue-shifted OH maser spot which has been shown to be the ampliﬁed stellar image.Thus, also the brightest H2O maser spot seems to be emission from the stellar radio-photosphere ampliﬁed by the maser medium at the line of sight.4.DiscussionThe observations of an ampliﬁed stellar image in the H2O masers of U Her indicate that at least for the brightest spot at this epoch the maser beaming is radial.Reid& Menten(1997)have detected22GHz continuum emis-sion from a small sample of Mira stars,ﬁnding the typ-ical stellar brightness temperature to be T∗=1600K. Compared to their estimate of the maser excitation tem-perature(≈10K),this is strong enough to inﬂuence the H2O maser medium and produce a stellar image,as the increased seed radiation from the star will cause the ra-dial maser beam to be brighter.Since the H2O masers are found to be mostly unsaturated,slight changes in density, pumping and velocity structure have a strong eﬀect on the maser and the relative strength of the maser features and the ampliﬁed stellar image may be less dominant than the OH,as is demonstrated by the detection by Reid& Menten(1990)of an H2O maser feature at the stellar po-sition of W Hya which was several orders of magnitude weaker than the strong feature observed here.The H2O masers around U Her have been observed before with MERLIN,the VLA and the VLBA.VLA ob-servations by Colomer et al.(2000),and MERLIN obser-vations by Bains et al.(in preparation)show an incom-plete ring structure with a scale of150−200mas.The brightest maser spot seen in our MERLIN observations corresponds in velocity with the masers on the edge of the ring structure.So somewhat surprisingly,our astrometric results indicate that the star is not in the center of this ring.The maser spots detected with high resolution VLBA observations do not show any indication of circular struc-ture(Vlemmings et al.2002).They have a linear extent of≈60−70mas and they most likely correspond to the brightest VLA and MERLIN features.5.ConclusionsOur observations have shown that the circumstellar H2O maser can amplify the stellar image and produce a strong stellar image,a phenomenon previously detected at the OH maser transitions.Although this eﬀect is not neces-sarily strong in all H2O masers,it can be very valuable for astrometric purposes.Accurate astrometry of the stellar image can be used to determine the location of the various maser species in the CSE with respect to each other and the star.Simultaneous,high resolution observations sig-niﬁcantly improve our understanding of the kinematics in the ing the stellar image in H2O masers,it will also be possible to determine the stellar trajectory and distance with a higher accuracy than with OH masers.However,because of the high variability of H2O masers additional monitoring will have to be performed to show if the stellar image is persistent enough for a long term monitoring campaign.Acknowledgments:This project is supported by NWO grant614-21-007.MERLIN is a National Facility oper-ated by the University of Manchester at Jodrell Bank Observatory on behalf of PPARC.We also thank the ref-eree Mark Reid for valuable input.ReferencesBeasley,A.J.,Gordon,D.,Peck,A.,et al.,2002,ApJS141,13. 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