The discovery of the planet Uranus took place on March 13, 1781 by an astronomer William Herschel, who, looking at the sky through an optical telescope, initially mistook this planet for an ordinary comet. It was W. Herschel who came up with the approach to studying stellar systems using powerful telescopes through careful and labor-intensive observations - an approach that essentially laid the foundation for “scientific” astronomy.

Later it was revealed that Uranus had been repeatedly observed in the sky before, but was mistaken for one of the many stars. This is evidenced by the earliest record of a certain “star”, made back in 1690 John Flamsteed, who classified it as the 34th star of Taurus according to one of the stellar magnitude notation systems accepted at that time.

English astronomer William Herschel - discoverer of the planet Uranus

On the day of the discovery of Uranus, during routine evening observations, Herschel noticed unusual star in the vicinity of faint stars, which looked larger than its neighbors. The object was moving along the ecliptic and had a pronounced disk. Thinking it was a comet, the astronomer shared his observations with other astronomers about its discovery.

A few months later, a famous scientist - academician of the St. Petersburg Academy of Sciences Andrey Ivanovich Leksel and academician of the Paris Academy of Sciences Pierre-Simon Laplace managed to calculate the orbit of a new celestial body. They proved that W. Herschel discovered not a comet, but a new planet located after Saturn.

Herschel himself gave the name to the planet Georgium Sidus(or Georg's Planet) in honor of King George III of England, his patron. Among scientists, the planet was named after the name of the astronomer himself. The established name of the planet “Uranus” was initially taken temporarily, as was traditionally accepted, from ancient mythology. And only in 1850 this name was finally established.

Uranus is a gas giant planet. In the figure you can see the comparative size of Uranus relative to our planet

Further study of the planet Uranus

The planet Uranus is approximately 3 billion kilometers away from the Sun and is almost 60 times the volume of the Earth. The discovery of a planet of this magnitude was the first in the history of science to detect planets using a powerful telescope, since the previously known five planets had long been observed only in the sky.

The new planet showed that the solar system is more than twice as wide and brought glory to its discoverer.

IN modern times Uranus has only been visited once spaceship Voyager 2, flying past at a distance of 81,500 kilometers on January 24, 1986.

Voyager 2 managed to transmit more than a thousand images of the planet's surface and a lot of other data about the planet, its satellites, the presence of rings, the composition of the atmosphere, information about the magnetic field and circumplanetary space.

Using various instruments, the ship studied the composition of the previously known one ring, and discovered two more new circumplanetary rings of Uranus. According to the data obtained, it became known that the rotation period of the planet is 17 hours 14 minutes.

Uranus has been discovered to have a magnetosphere that is significant in size and equally unusual.

To this day, the study of Uranus is difficult due to the planet’s significant remoteness. Despite this, large astronomical observatories continue to observe the planet. And in just a few recent years Six new moons were discovered around Uranus.

The discovery of Uranus was important event, and happened in 1781. This was done by William Herschel, an English astronomer. And this happened thanks to his diligence, observation and determination.

William Herschel - astronomer and discoverer of the planet Uranus.

William Herschel is one of the most famous people in astronomy. He is responsible for several discoveries, including the satellites of Uranus, Titania and Oberon. However, the fate of this man was very difficult, because initially he was a musician in a military orchestra and he wrote 24 symphonies! He was born in Germany in 1738, and moved to England in 1775, while serving in the army with his regiment, from where he left for the sake of music.

Herschel's path to astronomy was winding. At first he got carried away mathematical theory music, and mathematics led him to optics, and here he became interested in astronomy. And since he was poor and could not afford to buy a ready-made telescope, in 1773 he began polishing mirrors and constructing telescopes for himself and for sale. His first telescope was with focal length 7 feet (about 2 meters), with which he immediately began to study the sky.

Herschel's main rule when making observations was simple - not to leave a single, even tiny piece of the sky unstudied. The plan, of course, is grandiose, and no one has done this before. He was helped by his sister, Caroline Herschel, who also left her mark on the history of astronomy thanks to her dedicated work with her brother.

Discovery of Uranus

After 7 years of persistent observation of the vast sky, on March 13, 1781, William pointed his 7-foot telescope to the area between the constellations of Gemini and Taurus. And he was very surprised when one of the stars next to ζ Tauri appeared before him not as a bright point, but turned into a disk. Herschel immediately realized that he was not seeing a star at all, since stars at any magnification look like dots, only their brightness changes.

Herschel's 7-foot telescope, which was used to discover Uranus

William tried to observe the strange object with different eyepieces, that is, changing the magnification of the telescope to more and more. The greater the magnification, the larger the disk of the unknown object became, although the neighboring stars looked the same.

Puzzled by what he saw, William continued his observations and discovered that the unknown celestial body had own movement relative to other stars. Therefore, he decided that he had discovered a comet, although it was strange that it did not have a tail, and on March 17 he wrote about it in his journal.

In a letter to the Royal Society, Herschel wrote:

The first time I observed this comet was with a magnification of 227 times. My experience is that the diameter of stars, unlike planets, does not change proportionally when using lenses of higher magnification power; Therefore, I used 460 and 932 magnification lenses and found that the size of the comet increased in proportion to the change in the power of optical magnification, suggesting that it was not a star, since the sizes of the stars taken for comparison did not change. Moreover, at higher magnifications than its brightness allowed, the comet became blurry, difficult to distinguish, while the stars remained bright and clear - as I knew based on thousands of observations I had made. Repeated observation confirmed my assumptions: it really was a comet.

As soon as the strange comet became known among astronomers, it attracted close attention. Already in April, Astronomer Royal Neville Maskelyne suggested that this object could be either a comet or a previously unknown planet. What followed was routine work - observations, orbit calculations. And in 1783, Herschel recognized the fact that the strange object he discovered was a planet and named it George in honor of the king. On January 11, 1787, on the same day, he also discovered a pair of satellites of Uranus - Titania and Oberon. For the next 50 years, no one could see them - there was not enough telescope power. Currently, Uranus has 27 known moons. However, the discovery of Uranus was one of the largest in the life of this scientist.

The further fate of William Herschel

For his services, King George III awarded William Herschel a lifelong scholarship of 200 pounds, which was considerable money at that time. Since 1782, he began to work closely on improving the design of telescopes and in 1789 built the largest telescope in the world - with a mirror diameter of 126 cm and a focal length of 12 meters.

The largest telescope built by William Herschel.

During his life, Herschel made many discoveries. For example, it was previously thought that double stars in fact, they are simply located in the sky in such a way that they seem close. Herschel proved that some of them are star systems. He was the first to conclude that our Milky Way galaxy is actually a flat disk of stars, and the solar system is located inside it. He is responsible for many other discoveries, but that’s a completely different story.

It is worth noting that, in fact, William Herschel was an amateur astronomer who devoted a considerable part of his life to this science. Craters on the Moon, Mars, and Mimas, as well as some projects, are named in his honor.

Photo of Uranus. The rings are visible.

As for Uranus, little was known about it for a long time. This planet does not appear to be anything remarkable in appearance - no details are even noticeable on it, just a blue disk. However, in 1977, its rings were discovered (back in 1789, Herschel claimed to have seen the ring of Uranus, but they did not believe him), and then space research provided a lot of new data. And it turned out that Uranus is a rather extraordinary world that can surprise its researchers. But this is a topic for a separate article.

William Herschel is an outstanding English astronomer of German origin.

Born in Hanover (Germany) on November 15, 1738 in the family of a musician. Having received home education and becoming, like his father, a musician, he entered the military orchestra as an oboist and was sent to England as part of the regiment. Then he left with military service and taught music for some time. Wrote 24 symphonies.

In 1789 he was elected a foreign honorary member of the St. Petersburg Academy of Sciences. He died on August 23, 1822. On his gravestone it is written: “Broken the bars of heaven.”

Passion for astronomy

Gradually, while studying composition and music theory, Herschel came to mathematics, from mathematics to optics, and from optics to astronomy. He was 35 years old at that time. Without the funds to buy a large telescope, in 1773 he began polishing mirrors himself and constructing telescopes and other optical instruments, both for his own observations and for sale. The English King George III, himself a lover of astronomy, promoted Herschel to the rank of Astronomer Royal and provided him with the funds to build a separate observatory. Since 1782, Herschel and his sister Caroline, who assisted him, constantly worked to improve telescopes and astronomical observations. Herschel managed to convey his passion for astronomy to his family and friends. His sister Caroline, as already mentioned, helped him a lot in scientific works.

Having studied mathematics and astronomy under the guidance of her brother, Caroline independently processed his observations and prepared catalogs of Herschel’s nebulae and star clusters for publication. Caroline discovered 8 new comets and 14 nebulae. She was the first female researcher to be accepted as an equal into the cohort of English and European astronomers, who elected her an honorary member of the Royal Astronomical Society of London and the Irish royal academy. His brother also helped him Alexander. Son John, born in 1792, already in childhood showed remarkable abilities. He became one of the most famous English astronomers and physicists of the 19th century. His popular book “Essays on Astronomy” was translated into Russian and played a major role in the dissemination of astronomical knowledge in Russia.

Thanks to some technical improvements and an increase in the diameter of the mirrors, Herschel in 1789 produced the largest telescope of his time (focal length 12 meters, mirror diameter 49½ inches (126 cm)). However, Herschel's main works relate to stellar astronomy.

Observations of double stars

Herschel observed double stars to determine parallaxes(changes in the apparent position of an object relative to a distant background depending on the position of the observer). As a result of this, he concluded about the existence of star systems. Previously, it was believed that double stars were only randomly located in the sky in such a way that they appeared nearby when observed. Herschel established that double and multiple stars exist as systems of stars physically connected to each other and revolving around a common center of gravity.

By 1802, Herschel had discovered more than 2 thousand new nebulae and hundreds of new visual double stars. He also observed nebulae and comets and compiled their descriptions and catalogs (prepared for publication by his sister, Caroline Herschel).

Star scoop method

To study the structure of the stellar system, Herschel developed new method, based on statistical counts of stars in different parts of the sky, called the “star scoop” method. Using this method, he established that all the observed stars constitute a huge oblate system - the Milky Way (or Galaxy). He studied the structure Milky Way and came to the conclusion that the Milky Way has the shape of a disk, and the Solar system is part of the Milky Way. Herschel considered the study of the structure of our Galaxy to be his main task. He proved that the Sun with all its planets is moving towards the constellation Hercules. While studying the spectrum of the Sun, Herschel discovered the infrared invisible part of it - this happened in 1800. The discovery was made during the following experiment: by splitting sunlight prism, Herschel placed the thermometer just beyond the red band of the visible spectrum and showed that the temperature was rising, and, therefore, the thermometer was exposed to light radiation inaccessible to the human eye.

Discovery of the planet Uranus

Uranus- the seventh planet in terms of distance from the Sun, the third in diameter and fourth in mass. Herschel discovered it in 1781. Named after greek god the sky of Uranus, the father of Kronos (in Roman mythology, Saturn) and the grandfather of Zeus.

Uranus became the first planet discovered in modern times using a telescope. William Herschel announced the discovery of Uranus on March 13, 1781. Although Uranus is sometimes visible to the naked eye, earlier observers did not realize it was a planet due to its dimness and slow motion.

Herschel's astronomical discoveries

• Planet Uranus On March 13, 1781, Herschel dedicated this discovery to King George III and called open planet in his honor - "George's Star", but the name did not come into use.
• Saturn's moons Mimas and Enceladus in 1789
• Moons of Uranus Titania and Oberon.
• Introduced the term "asteroid".
• Defined movement solar system towards the constellation Hercules.
• Opened infrared radiation.
• Installed that galaxies are collected in huge “layers”, among which he singled out the supercluster in the constellation Coma Berenices. He was the first to express the idea of ​​cosmic evolution under the influence of gravity.
  

(1738-1822) - founder of stellar astronomy, foreign honorary member of the St. Petersburg Academy of Sciences (1789). Using the telescopes he made, he carried out systematic surveys of the starry sky, studied star clusters, double stars, and nebulae. He built the first model of the Galaxy, established the movement of the Sun in space, discovered Uranus (1781), its 2 satellites (1787) and 2 satellites of Saturn (1789).

The first attempts to penetrate deeper into the secret of the structure starry universe through careful observations using the most powerful telescopes, they are associated with the name of the astronomer William Herschel.

Friedrich Wilhelm Herschel was born on November 15, 1738 in Hanover in the family of oboist of the Hanoverian Guard Isaac Herschel and Anna Ilse Moritzen. Herschel's Protestants came from Moravia, which they probably left for religious reasons. The atmosphere of the parental home can be called intellectual. “Biographical note”, Wilhelm’s diary and letters, his memories younger sister Caroline takes us into the house and world of Herschel's interests and shows him truly titanic work and passion that created an outstanding observer and researcher.

Herschel received an extensive but unsystematic education. Classes in mathematics, astronomy, philosophy revealed his ability to exact sciences. But, besides this, Wilhelm had great musical abilities and at the age of fourteen he joined the regimental orchestra as a musician. In 1757, after four years of military service, he left for England, where his brother Jacob, the bandmaster of the Hanoverian regiment, had moved a little earlier.

Without a penny in his pocket, William, renamed William in England, began copying notes in London. In 1766 he moved to Bath, where he soon achieved great fame as a performer, conductor and music teacher. But such a life could not completely satisfy him. Herschel's interest in natural science and philosophy and constant independent education led him to become interested in astronomy. “What a pity that music is not a hundred times more difficult than science, I love activity and I need something to do,” he wrote to his brother.

In 1773, William Herschel acquired a number of works on optics and astronomy. Smith's Complete System of Optics and Ferguson's Astronomy became his reference books. In the same year, he first looked at the sky through a small telescope with a focal length of about 75 cm, but observations with such a low magnification did not satisfy the researcher. Since there was no money to buy a higher-aperture telescope, he decided to make it himself.

Having purchased necessary tools and blanks, William Herschel independently cast and polished the mirror for his first telescope. Having overcome great difficulties, Herschel in the same 1773 produced a reflector with a focal length of more than 1.5 m. Herschel polished the mirrors by hand (he created a machine for this purpose only fifteen years later), often working for 10, 12 and even 16 hours in a row , since stopping the grinding process deteriorated the quality of the mirror. The work turned out to be not only hard, but also dangerous; one day, while making a blank for a mirror, the melting furnace exploded.

Sister Caroline and brother Alexander were William's faithful and patient assistants in this difficult work. Hard work and enthusiasm yielded excellent results. The mirrors, made by William Herschel from an alloy of copper and tin, were of excellent quality and gave perfectly round images of the stars.

As the famous American astronomer Charles Whitney writes, “from 1773 to 1782, the Herschels were busy turning from professional musicians into professional astronomers."

In 1775, William Herschel began his first “sky survey.” At this time he continued to earn his living musical activity, but his true passion was astronomical observations. In between music lessons, he made mirrors for telescopes, gave concerts in the evenings, and spent his nights observing the stars. For this purpose, Herschel proposed an original new way“star scoops”, i.e. counting the number of stars in certain areas of the sky.

On March 13, 1781, while observing, Herschel noticed something unusual: “Between ten and eleven in the evening, while I was studying the faint stars in the neighborhood of N Gemini, I noticed one that looked larger than the rest. Surprised by its unusual size, I compared it with N Gemini and a small star in the square between the constellations Auriga and Gemini, and found that it was significantly larger than either of them. I suspected it was a comet." The object had a pronounced disk and was moving along the ecliptic. After informing other astronomers about the discovery of the “comet,” Herschel continued to observe it.

A few months later, two famous scientists - academician of the St. Petersburg Academy of Sciences D.I. Lexel and academician of the Paris Academy of Sciences Pierre Simon Laplace, having calculated the orbit of an open celestial object, proved that Herschel discovered a planet that was located beyond Saturn. The planet, later named Uranus, was almost 3 billion km from the Sun and was more than 60 times the volume of the Earth. For the first time in the history of science, a new planet was discovered, since the previously known five planets had been observed in the sky for centuries. The discovery of Uranus expanded the boundaries of the solar system more than twice and brought fame to its discoverer.

Nine months after the discovery of Uranus, on December 7, 1781, William Herschel was elected a member of the Royal Astronomical Society of London and was awarded a doctorate from Oxford University and gold medal of the Royal Society of London (in 1789 the St. Petersburg Academy of Sciences elected him an honorary member).

The discovery of Uranus shaped Herschel's career. King George III, himself an amateur astronomer and patron of the Hanoverians, appointed him "Astronomer Royal" in 1782 with an annual salary of £200. The king also provided him with funds to build a separate observatory at Slough, near Windsor. Here William Herschel, with youthful fervor and extraordinary constancy, began astronomical observations. According to Arago's biographer, he left the observatory only to present to the royal society the results of his tireless labors.

V. Herschel continued to devote his main attention to improving telescopes. He discarded the second small mirror that had been used until then and thereby significantly increased the brightness of the image. Gradually Herschel increased the diameters of the mirrors. Its pinnacle was a telescope built in 1789, a giant for that time, with a tube 12 m long and a mirror with a diameter of 122 cm. This telescope remained unsurpassed until 1845, when the Irish astronomer W. Parsons built an even larger telescope - almost 18 meters long with a mirror diameter 183 cm.

Using the latest telescope, William Herschel discovered two moons of Uranus and two moons of Saturn. Thus, the name of Herschel is associated with the discovery of several celestial bodies in the solar system. But this is not the main significance of his remarkable activity.

Even before Herschel, several dozen double stars were known, but such celebrity couples were viewed as random encounters between their component stars, and binary stars were not assumed to be widespread throughout the Universe. Herschel carefully examined different participation sky for many years and discovered over 400 double stars. He studied the distances between the components (in angular measures), their color and apparent gloss. In some cases, stars previously considered double turned out to be triple and quadruple stars (multiple stars). Herschel came to the conclusion that double and multiple stars are systems of stars physically connected to each other and, as he was convinced, revolving around a common center of gravity, according to the law of universal gravitation.

William Herschel was the first astronomer in the history of science to systematically study double stars. Since ancient times, a bright nebula in the constellation Orion, as well as a nebula in the constellation Andromeda, visible to the naked eye, have been known. But only in the 18th century, as telescopes improved, many nebulae were discovered. Immanuel Kant and Lambert believed that nebulae are entire star systems, other Milky Ways, but removed to colossal distances at which individual stars cannot be distinguished.

V. Herschel did a great job discovering and studying new nebulae. He used the ever-increasing power of his telescopes to do this. Suffice it to say that the catalogs he compiled based on his observations, the first of which appeared in 1786, number about 2,500 nebulae. Herschel's task, however, was not simply to find nebulae, but to reveal their nature. Through his powerful telescopes, many nebulae were clearly divided into individual stars and thus turned out to be star clusters far from the solar system. In some cases, the nebula turned out to be a star surrounded by a nebulous ring. But other nebulae were not divided into stars even with the help of the most powerful - 122-centimeter telescope

At first, Herschel concluded that almost all nebulae are actually collections of stars and the most distant of them will also decompose into stars in the future - when observed with even more powerful telescopes. At the same time, he admitted that some of these nebulae are not star clusters within the Milky Way, but independent star systems. Further research forced William Herschel to deepen and complement his views. The world of nebulae turned out to be more complex and diverse than previously thought.

Continuing to tirelessly observe and reflect, Herschel recognized that many of the observed nebulae could not be decomposed into stars at all, since they consisted of much more rarefied matter (“luminous liquid,” as Herschel thought) than stars. Thus, Herschel came to the conclusion that nebulous matter, like stars, is widespread in the Universe. Naturally, the question arose about the role of this substance in the Universe, about whether it was the material from which stars arose. Back in 1755, Imanuel Kant put forward a hypothesis about the formation of entire stellar systems from originally existing scattered matter. Herschel expressed the bold idea that various types indecomposable nebulae represent different stages of star formation. By densifying the nebula, either a whole cluster of stars or one star is gradually formed from it, which at the beginning of its existence is still surrounded by a nebulous envelope. If Kant believed that all the stars of the Milky Way were once formed simultaneously, then Herschel was the first to suggest that stars have different ages and the formation of stars continues continuously and occurs in our time.

This idea of ​​William Herschel was later forgotten, and erroneous opinion the simultaneous origin of all stars in the distant past has long dominated science. Only in the second half of the 20th century, based on the enormous successes of astronomy and especially the works of Soviet scientists, differences in the ages of stars were established. Entire classes of stars have been studied that undoubtedly exist for a few millions of years, in contrast to other stars whose age is determined by billions of years. Herschel's views on the nature of nebulae in general outline confirmed modern science, which established that gas and dust nebulae are widespread in our and other galaxies. The nature of these nebulae turned out to be even more complex than Herschel could have imagined.

At the same time, William Herschel, even at the end of his life, was convinced that some nebulae were distant star systems that would eventually be decomposed into individual stars. And in this he, like Kant and Lambert, turned out to be right.

As already mentioned, in the 18th century the proper motion of many stars was discovered. Herschel, through calculations, managed to convincingly prove in 1783 that our solar system is moving towards the constellation Hercules.

But William Herschel considered his main task to be elucidation of the structure of the Milky Way star system, or our Galaxy, its shape and size. He did this for several decades. At that time he had no data at his disposal either about the distances between the stars, or about their location in space, or about their sizes and luminosity. Without this data, Herschel assumed that all stars had the same luminosity and were distributed evenly in space, so that the distances between them were more or less the same, and the Sun was located near the center of the system. At the same time, Herschel did not know the phenomenon of light absorption in cosmic space and believed, moreover, that even the most distant stars of the Milky Way were accessible to his giant telescope. Using this telescope, he counted stars in different parts of the sky and tried to determine how far our star system extended in one direction or another.

But Herschel's initial assumptions were wrong. Now it is known that stars differ among themselves in luminosity and that they are distributed unevenly in the Galaxy. The Galaxy is so large that its boundaries were not accessible even to Herschel’s giant telescope, so he could not come to correct conclusions about the shape of the Galaxy and the position of the Sun in it, and he greatly underestimated its size.

William Herschel also dealt with other issues of astronomy. By the way, he unraveled the complex nature solar radiation and concluded that it contains light, heat and chemical rays (radiation not perceived by the eye). In other words, Herschel anticipated the discovery of rays that go beyond the normal solar spectrum - infrared and ultraviolet.

Herschel began his scientific activity as a modest amateur who had the opportunity to devote only his own time to astronomy free time. Teaching music remained his source of livelihood for a long time. Only in old age did he acquire the financial resources to pursue science.

The astronomer combined the features of a real scientist and wonderful person. Herschel was a most skillful observer, an energetic researcher, and a deep and purposeful thinker. At the very zenith of his fame, he remained charming, kind and a simple person, which is characteristic of deep and noble natures.

William Herschel managed to convey his passion for astronomy to his family and friends. His sister Caroline helped him a lot in his scientific work. Having studied mathematics and astronomy under the guidance of her brother, Caroline independently processed his observations and prepared catalogs of Herschel’s nebulae and star clusters for publication. Dedicating a lot of time to observations, Caroline discovered 8 new comets and 14 nebulae. She was the first female researcher to be accepted as an equal into the cohort of English and European astronomers, who elected her an honorary member of the Royal Astronomical Society of London and the Royal Irish Academy

Uranus - discovered by William Herschel in 1781. Uranus has 27 moons and 11 rings.
Average distance from the Sun	2871 million km.
Weight	8.68 10 25 kg
Density	1.30 g/cm 3
Equatorial diameter	51118 km
Effective temperature	57 K
Period of rotation around an axis	0.72 Earth days
Period of rotation around the Sun	84.02 Earth years
Largest satellites	Titania, Oberon, Ariel, Umbriel
Titania - discovered by W. Herschel in 1787
Average distance to planet	436298 km
Equatorial diameter	1577.8 km
Orbital period around the planet	8.7 Earth days

Among the most important discoveries, which belong to researchers of the Universe, one of the first places is occupied by the discovery of the seventh big planet Solar system - Uranus. There has never been another event like this in history, and it deserves to be told about it in more detail. It started when a young man came to England in search of work German musician named William Herschel (1738-1822).

As a child, William came across Robert Smith's book "The System of Optics", and under its influence he developed a great desire for astronomy.

At the beginning of 1774, William built his first reflecting telescope with a focal length of about 2 m. In March of the same year, he began regular observations of the starry sky, having previously given himself the word “not to leave a single, even the most insignificant piece of the sky without proper research.” No one has ever made such observations. Thus began William Herschel's career as an astronomer. Herschel's faithful assistant in all his affairs was Caroline Herschel (1750-1848). This selfless woman was able to subordinate her personal interests to her brother’s scientific hobbies. And her brother, who had set himself a grandiose “stellar goal,” constantly strived to improve his means of observation. Following the 7-foot telescope, he builds a 10-foot one and then a 20-foot one.

Seven years of intense exploration of the immeasurable stellar “ocean” were already behind us when the evening of March 13, 1781 came. Taking advantage of the clear weather, William decided to continue his observations; The journal entries were kept by my sister. On that memorable evening, he set out to determine the position of some double stars in the region of the sky located between the “horns” of Taurus and the “feet” of Gemini. Suspecting nothing, William pointed his 7-foot telescope there and was amazed: one of the stars glowed in the form of a small disk.

All stars, without exception, are visible through a telescope as luminous points, and Herschel immediately realized that the strange luminary was not a star. To finally make sure of this, he twice replaced the telescope eyepiece with a stronger one. With increasing magnification of the tube, the diameter of the disk of the unknown object also increased, while nothing similar was observed for neighboring stars. Moving away from the telescope, Herschel began to peer into the night sky: the mysterious luminary was barely visible to the naked eye...

Uranus moves around the Sun in an elliptical orbit, the semimajor axis of which (the average heliocentric distance) is 19.182 times greater than that of the Earth, and amounts to 2871 million km. The orbital eccentricity is 0.047, which means the orbit is quite close to circular. The orbital plane is inclined to the ecliptic at an angle of 0.8°. Uranus completes one revolution around the Sun in 84.01 Earth years. The period of Uranus's own rotation is approximately 17 hours. The existing scatter in determining the values ​​of this period is due to several reasons, of which two are main: the gas surface of the planet does not rotate as a single whole and, in addition, no noticeable local inhomogeneities were found on the surface of Uranus that would help clarify the length of the day on the planet. The rotation of Uranus has a number of distinctive features: the axis of rotation is almost perpendicular (98°) to the orbital plane, and the direction of rotation is opposite to the direction of revolution around the Sun, that is, the opposite (of all other major planets the opposite direction of rotation is observed only on Venus).

Further observations showed that the mysterious object has its own motion relative to the stars surrounding it. From this fact, Herschel concluded that he had discovered a comet, although no tail or foggy shell characteristic of comets was visible. Herschel did not even think about the fact that this could be a new planet.

On April 26, 1781, Herschel presented his “Report on a Comet” to the Royal Society (English Academy of Sciences). Soon, astronomers began observing the new “comet.” They were looking forward to the hour when Herschel's comet would approach the Sun and give people an enchanting spectacle. But the “comet” was still slowly making its way somewhere near the borders of the solar domain.

By the summer of 1781, the number of observations of the strange comet was already quite sufficient for an unambiguous calculation of its orbit. They were performed with great skill by the St. Petersburg academician Andrei Ivanovich Leksel (1740-1784). He was the first to establish that Herschel did not discover a comet at all, but a new one, not yet known to anyone known planet, which moves in a nearly circular orbit located 2 times further from the Sun than the orbit of Saturn and 19 times further than the orbit of the Earth. Lexel also determined the circulation period new planet around the Sun: it was equal to 84 years. So, William Herschel turned out to be the discoverer of the seventh planet in the solar system. With its appearance, the radius of the planetary system immediately doubled! Nobody expected such a surprise.

The news of the discovery of a new large planet quickly spread throughout the world. Herschel was awarded a gold medal and elected a member Royal Society, he was awarded many scientific degrees, including an honorary member of the St. Petersburg Academy of Sciences. And, of course, the English King George III himself wanted to see the modest “star lover,” who suddenly became a world celebrity. By order of King Herschel, he and his instruments were taken to the royal residence, and the entire court became interested in astronomical observations. Fascinated by Herschel's story, the king promoted him to the position of court astronomer with an annual salary of 200 pounds. Now Herschel was able to devote himself entirely to astronomy, and music remained for him only a pleasant entertainment. At the suggestion of the French astronomer Joseph Lalande, the planet for some time bore the name of Herschel, and later, according to tradition, it was given the mythological name - Uranus. So in Ancient Greece was called the god of the sky.

Having received a new appointment, Herschel settled with his sister in the town of Slow, near Windsor Castle - his summer residence English kings. With redoubled energy he set about organizing a new observatory.

It's impossible to even list everything scientific achievements Herschel. They discovered hundreds of double, multiple and variable stars, thousands of nebulae and star clusters, satellites of planets and much more. But only the discovery of Uranus would be enough for the name of the inquisitive, self-taught astronomer to forever go down in the history of the development of world science. And the house in Slow, where William Herschel once lived and worked, is now known as the “Observatory House”. Dominique François Arago called it "the corner of the world in which it was made greatest number discoveries."