Pierre-Simon Laplace is a French mathematician, astronomer and academician of French Academy of Sciences. He is the main founder of celestial mechanics, one of the founders of celestial evolution chemistry and the founder of analytical probability theory, so he can be said to be a pioneer of applied mathematics.
Laplace focused his attention on the study of celestial mechanics. He applied Newton's law of universal gravitation to the whole solar system, and in 1773, he solved a famous problem at that time: explaining why Jupiter's orbit is shrinking and Saturn's orbit is expanding. Laplace proved the invariance of the average motion of the planet by mathematical method, that is, the orbital size of the planet only changes periodically, and it is proved to be the cubic of eccentricity and inclination. This is the famous Laplace theorem. After that, he began to study the stability of the solar system. From 1784 to 1785, he found that the gravitational component of a celestial body to any particle outside it can be expressed by a potential function, which satisfies a partial differential equation, that is, the famous Laplace equation.
1786 proves that the eccentricity and inclination of planetary orbits are always small and constant, and can be adjusted automatically, that is, the perturbation effect is conservative and periodic, and will not accumulate or disappear.
1787 found that the acceleration of the moon is related to the eccentricity of the earth's orbit, which theoretically solved the last abnormal problem observed in solar system dynamics.
1796, his book "Cosmic System Theory" came out, in which he put forward the nebula hypothesis about the origin of planets, which had a great influence later. In this book, independent of Kant, he put forward the first scientific theory of the origin of the solar system-nebula theory.
He has been engaged in the research of planetary motion theory and lunar motion theory for a long time. In particular, he paid special attention to the study of celestial perturbation, general stability and stability dynamics of the solar system. On the basis of summarizing predecessors' research, he has made a lot of important achievements, which are embodied in the five volumes of Celestial Mechanics published by 1799 ~ 1825. This book puts forward the term celestial mechanics for the first time, which is a masterpiece of classical celestial mechanics. Therefore, he is known as the father of French Newton and celestial mechanics. 18 14, Laplace put forward such a scientific hypothesis: if an intelligent creature can determine the current motion state from the largest celestial body to the lightest atom, it can calculate the past state and future state of the whole universe according to the laws of mechanics. Later generations called his so-called intelligent creatures Laplacian demons.
2. Copernicus
Mikolaj kopernik (Polish: Nikolaj Kopernik,1February 47319-1May 24, 543, at the age of 70) was a Polish astronomer, mathematician, doctor of church law and priest during the Renaissance.
When Copernicus was 40 years old, he put forward Heliocentrism, which denied the authority of the church and changed people's views on nature and themselves. At that time, the Roman Catholic Church thought that his Heliocentrism violated the Bible. Copernicus still firmly believed in Heliocentrism and thought that Heliocentrism was not contradictory to him. After years of observation and calculation, he completed his masterpiece "The Theory of the Operation of Celestial Bodies".
1533, 60-year-old Copernicus made a series of speeches in Rome, but it was not until he was nearly 70 years old that he finally decided to publish them. 1543 On May 24th, Copernicus received a book written by him from the publishing house on the day of his death.
Copernicus' "Heliocentrism" corrected people's world outlook. Copernicus was a giant in the European Renaissance. He devoted his whole life to astronomical research, leaving a valuable legacy to future generations.
3. Charles Messier
Charles Messier (1730— 18 17) is a French astronomer. His achievement lies in numbering nebulae, clusters and galaxies, and making the famous "messier Cluster Nebula List".
1760, Delhi Hill retired and Charles Messier took over as a civil servant. In the process of searching for comets, messier, who is often confused with comets and other celestial bodies, has been making lists of comets and interstellar hazy objects since 1764. At the end of the same year, Charles Messier made a list of 40 celestial bodies. Since then, after 1765 found M4 1 in Canis major, five celestial bodies including M4 1-M45 have joined the list. 1769, the Great Comet (C/ 1769P 1) was discovered near Aries, so messier became a foreign academician of the Berlin Academy of Sciences. The following year, another comet was discovered and became a full member of the Paris Academy. Messier discovered 12 comets in his life.
Charles Messier published the first volume (M 1-M45), the second volume (M46-M68) and the third volume (messier cluster nebula list) in 177 1 784 respectively.
The celestial bodies listed in these lists are called "messier objects". For example, M3 1 stands for Andromeda galaxy. Considering the genre of the list, messier also includes binary stars (M40) or star clusters (M45). ).
Messier used a small telescope with a diameter of 5-7 cm. Later, when large telescopes appeared, it was found that messier objects contained many nebulae, star clusters and galaxies.
4. Galileo
Galileo (1564 February 15—1642 June 5438+0.8). Italian mathematician, physicist and astronomer, one of the founders of modern experimental science. Born in Pisa, Italy, died in Chetri, Italy. Galileo's surname is Galileo, and his full name is galileo galilei, but now people usually call him Galileo instead of his surname.
Galileo was the first scientist who made great achievements in observing celestial bodies with a telescope. 1609, after knowing that the Dutch had telescopes, Galileo made an astronomical telescope (later called galileo telescope) and used it to observe celestial bodies, and discovered many previously unknown astronomical phenomena. He found that with the increase of telescope magnification, the number of stars he saw also increased; The Milky Way is made up of countless independent stars; There are uneven phenomena on the surface of the moon (the first map of the moon was drawn by hand), and the phenomenon of Venus' profit and loss; Jupiter has four satellites (actually, the largest four of Europa, now called Galileo satellite). He also discovered sunspots, and believed that sunspots were phenomena on the sun. He concluded from the rotation period of sunspots on the sun's surface that the rotation period of the sun is 28 days (actually 27.35 days). 1637, under the condition of poor eyesight, he also found the Sunday of the moon and the Zhou Yue libration. These discoveries ushered in a new era of astronomy.
Galileo was the first to observe the phenomena of Saturn's rings, sunspots, Moon Mountain, Venus and Mercury, and the periodic equivalence between Jupiter's satellite and Venus, and summed up the laws of free fall, inertia and Galileo's relativity from experiments. Thus overthrew many hypotheses of Aristotle's physics, laid the foundation of classical mechanics, refuted Ptolemy's geocentric theory, and strongly supported Copernicus' Heliocentrism.
5. Claudius Ptolemy
Claudius Ptolemy (ancient Greek: κ λ α? διο? Πτολεμα? ο? ; Latin ClaudiusPtolemaeus, about 90- 168), also translated as Tolemei or Duolumou, is said to have been born in the Hellenistic city of Egypt. A famous astronomer, geographer, astrologer and optician under the rule of the Roman Empire.
Ptolemy summed up the achievements of ancient Greek astronomy and wrote thirteen volumes of astronomical works. The duration of one year is determined, the catalogue is compiled, the correction caused by precession and refraction is explained, and the calculation method of solar eclipse is given. He used a large number of observations and research results of Greek astronomers, especially Hipparchus (also translated as Iba Valley), and systematically demonstrated various geocentric systems that explained the motion of celestial bodies with eccentric circles or small wheel trains. Later generations named this geocentric system after him, calling it Ptolemaic geocentric system. This masterpiece was an encyclopedia of astronomy at that time, and it was a must-read book for astronomers before Kepler's era.
Astronomical masterpiece, the peak of Greek astronomy and cosmology in the past 500 years, ruled the astronomical world for 13 centuries. Such a book with complicated knowledge cannot be completed by one person. There is no need to hide Ptolemy's dependence on his pioneers, especially Hippocrates. The basic problem he faces is to try to explain the motion of celestial bodies on the premise that the universe is centered on the earth and all celestial bodies run in a completely circular orbit at a uniform speed. Because the actual celestial body moves around the center outside the earth in a variable-speed elliptical orbit, in order to maintain the original basic assumption, some very complicated geometries must be considered. Ptolemy used three complicated original ideas: current wheel, eccentric circle and even wheel. He can give reasonable descriptions of the orbits of Mars, Venus and Mercury respectively, but if they are put in a model, their scales and periods will conflict. But no matter what shortcomings this system has, it still prevailed for 1300 years, and it was not overthrown by Copernicus until 15 century.
6. Johannes Kepler
Johannes kepler (157165438+February 27th-1630110/5) was born in Wildstadt, Wü rttemberg, and died. An outstanding astronomer, physicist and mathematician in Germany.
Kepler studied at the University of Tubingen, and received his bachelor's degree from 65438 to 0588, and his master's degree three years later. At that time, most scientists refused to accept Copernicus' Heliocentrism. When studying at the University of Tubingen, he heard Heliocentrism's logical exposition and soon believed it.
1630165438+1October15th, Johannes Kepler died at the age of 58 in regensburg, the Bavarian Principality of the Holy Roman Empire.
Kepler discovered three laws of planetary motion, namely, orbit law, area law and periodicity law. These three laws can be described as follows: all planets run in elliptical orbits of different sizes; At the same time, the area swept by the planet in the radial direction on the orbital plane is equal; The square of the planet period of revolution is proportional to the cube of its distance from the sun. These three laws finally won him the reputation of "sky legislator". At the same time, he also made important contributions to optics and mathematics. He is the founder of modern experimental optics.
7. tycho brahe
Tycho Brahe (1546 65438+February 14- 160 1 year 65438+1October 24th) was a Danish astronomer and astrologer. 1546121410 was born in a noble family in Kiuddestep, Huskin Virginia, and Tycho died in Prague at the age of 55. On June1572165438+1October1day, Tycho discovered a new star in Cassiopeia. Later, at the invitation of King Frederick II of Denmark, Tianbao Observatory was built on Brunei Island. After 20 years of observation, Tycho discovered many new astronomical phenomena. Tycho brahe once proposed a cosmic structure system between geocentric theory and Heliocentrism, and/kloc-0 was once accepted after it was introduced to China in the early 7th century. The accuracy of Tycho's observation is beyond the reach of his contemporaries. A catalogue compiled by Tycho is quite accurate and still valuable today.
Tycho was the last and greatest astronomer who observed with the naked eye. Tycho entered the University of Copenhagen to study law and philosophy as early as the age of thirteen. He originally intended to study theology, but he observed a solar eclipse in 1560 and turned to astronomy and mathematics. Later he went to Germany for further training and education. 1597, Tycho left Denmark for Germany at the invitation of German King Rudolf II (Tycho attended his coronation ceremony several years ago) and settled in Prague New District. Here he made an important discovery, and discovered Kepler, a German youth assistant.
8. Hipachas
Hippocius (about 190- BC 125) was the greatest astronomer and mathematician in ancient Greece. He compiled 1022 star position table, and distinguished stars by "magnitude" for the first time; Ptolemy theorem was put forward. Discovered the precession phenomenon.
Hipahas calculated that the length of a year is 365 and 1/4 days, minus 1/300 days; It is found that the distance between the white arch point and the yellow-white intersection point is 30 times and 1/6 times the diameter of the earth. For centuries, the movement tables of the sun and the moon have been compiled and used to calculate eclipses. He discovered new stars in 134 BC, which prompted him to compile a catalogue of the positions and brightness of 850 constant stars. He compared his observation results of the ecliptic with those of his predecessors, found the slow movement of the intersection of the ecliptic and the equator-precession, and determined that the annual difference was 45 "or 46" per year. The method of expressing geographical position by latitude and longitude and the method of projection drawing were also invented.
In order to study astronomy, he founded trigonometry and sphericity. Hipachas left a lot of observation data. Later generations often use his observations when determining various periods and parameters of planets. In 17 18, Harley compared his observation results with hipparchus' records and found the phenomenon of stars' self-motion. Hipachas's works have not been handed down, and what we know about him now comes from Ptolemy's works.
9. Guo Shoujing
Guo Shoujing (123 1 year-13 16 years) was thoughtful. Xingtai County, xing zhou (now Xingtai City, Hebei Province). Famous astronomer, mathematician and expert in water conservancy engineering in Yuan Dynasty. In his early years, he studied under Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu, Liu. Yuan Renzong extended his life for three years (13 16), and Guo Shoujing died at the age of 86. He is the author of fourteen kinds of astronomical calendar works, such as "Push Step" and "Licheng".
Guo Shoujing has made outstanding achievements in astronomy, calendar, water conservancy and mathematics. From the 13th year of Zhiyuan (1276), it took four years to revise the new calendar, and a "chronograph calendar" was worked out, which was used for more than 360 years and became the most advanced calendar in the world at that time. In order to revise the calendar, Guo Shoujing also reformed and invented twelve new instruments, such as simple instrument and altimeter.
Guo Shoujing made many precise astronomical observations with his own improved and created astronomical instruments, which provided reliable observation basis for the compilation of chronicles. He engaged in and led many observation projects, such as the time of winter solstice, the distance and catalogue of 28 nights, the test of the four seas, the determination of ecliptic angle and some epoch times, most of which were the most accurate or close to the best in the ancient history of China. One of the most famous is the Four Seas Test. In the 16th year of Yuan Dynasty (1279), Guo Shoujing proposed to Kublai Khan in Yuan Shizu that the territory of Yuan Dynasty was much larger than before, and the length of sunrise and sunset in different places was different from the time of day, so the old calendar was no longer applicable, and it was necessary to carry out nationwide astronomical observation to compile a new calendar. Kublai Khan accepted Guo Shoujing's suggestion and sent fourteen probation officers to carry out astronomical observation in 27 places, which was later called "universal observation".
Guo Shoujing traveled thousands of miles from Shangdu (now Duolun) and Dadu (now Jinghua) to Nanhai via Henan, and personally took the exam along the way. At six locations, the length of ground shadow and the length of day and night from summer solstice were measured. The average error of the measured Arctic height is only 0.35; The average error of the newly measured 28-night distance is less than 5'; The new value of yellow-red intersection angle is measured, and the error is only 1'. The tropical year is 365.2425 days, which is completely consistent with the current Gregorian calendar. These observations provide scientific data for compiling calendars suitable for the whole country.
Edmund halley, 10
Edmund halley Harley, British astronomer Edmund (1656.1.8-1742.1.14) applied Newton's law to the motion of comets and correctly predicted that the comet now called Harley would make a regression motion.
Edmund halley, 1656 was born in England and graduated from Queen's College, Oxford University at the age of 20. After that, he gave up the chance to get a degree and went to St. Helena to set up a temporary observatory. There, Harley carefully observed the astronomical phenomena and compiled the first South Catalogue, which made up for the lack of only the North Catalogue in astronomy. Harley's southern star map contains the direction of 38 1 star. Published in 1678, when he was only 22 years old.
Harley's most famous contribution is his accurate prediction of comets. Harley found that the number of orbital elements of a comet appeared in 1682, which was similar to that observed in Kepler 1607 and Apyan 153 1 year, with an interval of 75 or 76 years. Harley's calculations predict that this comet will return at 1835 and 19 10. As a result, the comet arrived as scheduled. This comet is the "Halley's Comet" that almost everyone knows today. The mystery of the comet has been solved.
In addition, Harley discovered the star's self, which is another important discovery. Harley also proposed to use the opportunity of transit of venus to measure the distance between the sun and the earth, which provided a good method for accurately measuring the distance between the sun and the earth at that time. He also discovered the long-term acceleration of the moon's motion, which made an important contribution to the accurate study of the motion of the earth and the moon system.
Edwin Powell Hubble
Edwin powell hubble (1889165438+19531October 20-65438+September 28) is a famous American astronomer, one of the most famous figures in modern cosmology research, the founder of extragalactic astronomy and the first person to provide evidence of the expansion of the universe. He discovered the redshift phenomenon of most galaxies and established Hubble's law, which is considered as strong evidence of the expansion of the universe. At the same time, he is also the founder of galaxy astronomy and the pioneer of observational cosmology, and is called the father of galaxy astronomy.
Hubble made many contributions to the Department of Astronomy in the 20th century and was regarded as a great master. There are two most important ones: one is to confirm that galaxies are star systems equivalent to the Milky Way, which initiated galaxy astronomy and established a new concept of large-scale universe; Second, the discovery of the relationship between galaxy redshift and distance promoted the birth of modern cosmology.