Tycho Brahe

Life

Family

Tycho Brahe was born as heir to several of Denmark's most influential noble families. In addition to his immediate ancestry with the Brahe and the Bille families, he counted the Rud, Trolle, Ulfstand, and Rosenkrantz families among his ancestors. Both of his grandfathers and all of his great-grandfathers had served as members of the Danish king's Privy Council. His paternal grandfather and namesake, Thyge Brahe, was the lord of Tosterup Castle in Scania and died in battle during the 1523 Siege of Malmö during the Lutheran Reformation Wars.

His maternal grandfather, Claus Bille, lord to Bohus Castle and a second cousin of Swedish king Gustav Vasa, participated in the Stockholm Bloodbath on the side of the Kalmar Union king against the Swedish nobles. Tycho's father, Otte Brahe, a royal Privy Councilor (like his own father), married Beate Bille, a powerful figure at the Danish court holding several royal land titles. Tycho's parents are buried under the floor of the church of Kågeröd, four kilometres west of Knutstorp Castle.

Early years

Tycho was born on 14 December 1546, at his family's ancestral seat at Knutstorp (Knudstrup borg; Knutstorps borg), about 8 kilometres (5.0 mi) north of Svalöv in then Danish Scania (Swedish since 1658). He was the oldest of 12 siblings, 8 of whom lived to adulthood, including Steen Brahe and Sophia Brahe. His twin brother died before being baptized. Tycho later wrote an ode in Latin to his dead twin, which was printed in 1572 as his first published work. An epitaph, originally from Knutstorp, but now on a plaque near the church door, shows the whole family, including Tycho as a boy.

When he was only two years old Tycho was taken away to be raised by his uncle Jørgen Thygesen Brahe and his wife Inger Oxe, sister to Peder Oxe, Steward of the Realm, who were childless. It is unclear why Otte Brahe reached this arrangement with his brother, but Tycho was the only one of his siblings not to be raised by his mother at Knutstorp. Instead, Tycho was raised at Jørgen Brahe's estate at Tosterup and at Tranekær on the island of Langeland, and later at Næsbyhoved Castle near Odense, and later again at the Castle of Nykøbing on the island of Falster. Tycho later wrote that Jørgen Brahe "raised me and generously provided for me during his life until my eighteenth year; he always treated me as his own son and made me his heir".

From ages 6 to 12, Tycho attended Latin school, probably in Nykøbing. At age 12, on 19 April 1559, Tycho began studies at the University of Copenhagen. There, following his uncle's wishes, he studied law, but also studied a variety of other subjects and became interested in astronomy. At the university, Aristotle was a staple of scientific theory, and Tycho likely received a thorough training in Aristotelian physics and cosmology. He experienced the solar eclipse of 21 August 1560, and was greatly impressed by the fact that it had been predicted, although the prediction based on current observational data was a day off. He realized that more accurate observations would be the key to making more exact predictions. He purchased an ephemeris and books on astronomy, including Johannes de Sacrobosco's De sphaera mundi, Petrus Apianus's Cosmographia seu descriptio totius orbis and Regiomontanus's De triangulis omnimodis.

Jørgen Thygesen Brahe, however, wanted Tycho to educate himself in order to become a civil servant, and sent him on a study tour of Europe in early 1562. Fifteen-year-old Tycho was given as mentee to the 19-year-old Anders Sørensen Vedel. Tycho eventually talked Vedel into allowing him to pursue astronomy during the tour. Vedel and his pupil left Copenhagen in February 1562. On 24 March, they arrived in Leipzig, where they matriculated at the Lutheran Leipzig University. In 1563, he observed a close conjunction of the planets Jupiter and Saturn, and noticed that the Copernican and Ptolemaic tables used to predict the conjunction were inaccurate. This led him to realise that progress in astronomy required systematic, rigorous observation, night after night, using the most accurate instruments obtainable. He began maintaining detailed journals of all his astronomical observations. In this period, he combined the study of astronomy with astrology, laying down horoscopes for different famous personalities.

Tycho's nose

In 1566, Tycho left to study at the University of Rostock in what is now Germany. There he studied with professors of medicine at the university's famous medical school and became interested in medical alchemy and herbal medicine. On 29 December 1566 at the age of 20, Tycho lost part of his nose in a sword duel with a fellow Danish nobleman, his third cousin Manderup Parsberg. At an engagement party at the home of Professor Lucas Bachmeister on 10 December the two had drunkenly quarreled over who was the superior mathematician. On 29 December, the cousins resolved their feud with a duel in the dark. Though the two were later reconciled, in the duel Tycho lost the bridge of his nose and gained a broad scar across his forehead.

He received the best possible care at the university and wore a prosthetic nose for the rest of his life. It was kept in place with paste or glue and said to be made of silver and gold. In November 2012, Danish and Czech researchers reported that the prosthesis was actually made of brass after chemically analyzing a small bone sample from the nose from the body exhumed in 2010.

Science and life on Uraniborg

In April 1567, Tycho returned home from his travels, with a firm intention of becoming an astrologer. Although he had been expected to go into politics and the law, like most of his kinsmen, and although Denmark was still at war with Sweden, his family supported his decision to dedicate himself to the sciences. His father wanted him to take up law, but Tycho was allowed to travel to Rostock and then to Augsburg, where he built a great quadrant, then Basel, and Freiburg. In 1568, he was appointed a canon at Roskilde Cathedral in Denmark, a largely honorary position that allowed him to focus on his studies.

At the end of 1570, he was informed of his father's ill health, so he returned to Knutstorp Castle, where his father died on 9 May 1571. The war was over, and the Danish lords soon returned to prosperity. Soon, another uncle, Steen Bille, helped him build an observatory and alchemical laboratory at Herrevad Abbey, where Tycho was assisted by his keenest disciple, his younger sister Sophie Brahe. Tycho was acknowledged by King Frederick II, who proposed to him that an observatory be built to better study the night sky. After accepting this proposal, the location for the Uraniborg’s construction was set on an island called Hven, now Ven in the Sound not too far from Copenhagen, the earliest large observatory in Christian Europe.

Tycho Brahe was highly appreciated by King Frederick II, and he was accepted and supported by people of high social status. He was supported by the church. The support Tycho Brahe received from the king allowed him to continue his research and make significant contributions to the field of astronomy.

In the late 16th century, Tycho Brahe built an observatory called Uraniborg. It was built on the island of Hven located between the provinces of Zealand (Sjælland) and Scania (Skåne). The island was then an administrative part of Zealand. Later, after the Peace of Roskilde in 1658, Scania was conquered by the Swedes. In 1660, Hven became part of Sweden. In Tycho's time, it was all Denmark. He lived on Hven for approximately 21 years. He began to build Uraniborg in 1576 and moved there soon after. As Uraniborg was a significant and advanced observatory, it took years to complete.

Uraniborg was a place where Tycho Brahe could research and analyze his previous findings, as well as explore new discoveries. Tycho Brahe was an astronomer of the pre-telescope era. Using just his naked eye, he observed the planets, Moon, stars, and space and recorded everything he saw while completing a multitude of calculations daily. The location of Uraniborg was strategically chosen, with seclusion and support being the primary reasons for building on the island of Hven. Seclusion was essential for accurate observation, and gave Tycho Brahe a better way to focus on his work without worrying about interruptions from other people. Seclusion was also important for observation, as there was nothing interfering with time, light, or motion observations.

Exile and later years

When Frederick died in 1588, his son and heir Christian IV was only 11 years old. A regency council was appointed to rule for the young prince-elect until his coronation in 1596. The head of the council (Steward of the Realm) was Christoffer Valkendorff, who disliked Tycho after a conflict between them, and hence Tycho's influence at the Danish court steadily declined. Feeling that his legacy on Hven was in peril, he approached the Dowager Queen Sophie and asked her to affirm in writing her late husband's promise to endow Hven to Tycho's heirs.

He realized that the young king was more interested in war than in science, and was of no mind to keep his father's promise. King Christian IV followed a policy of curbing the power of the nobility, by confiscating their estates to minimize their income bases, by accusing nobles of misusing their offices and of heresies against the Lutheran church. Tycho, who was known to sympathize with the Philippists, followers of Philip Melanchthon, was among the nobles who fell out of grace with the new king. The king's unfavorable disposition towards Tycho was likely also a result of efforts by several of his enemies at court to turn the king against him.

In addition to Valkendorff, Tycho's enemies included the king's doctor Peter Severinus, who also had personal gripes with Tycho. Several gnesio-Lutheran Bishops suspected Tycho of heresy – a suspicion motivated by his known Philippist sympathies, his pursuits in medicine and alchemy, both of which he practiced without the church's approval, and his prohibiting the local priest on Hven to include the exorcism in the baptismal ritual. Among the accusations raised against Tycho were his failure to adequately maintain the royal chapel at Roskilde, and his harshness and exploitation of the Hven peasantry.

Tycho became even more inclined to leave when a mob of commoners, possibly incited by his enemies at court, rioted in front of his house in Copenhagen. Tycho left Hven in 1597, bringing some of his instruments with him to Copenhagen, and entrusting others to a caretaker on the island. Shortly before leaving, he completed his star catalogue giving the positions of 1,000 stars. After some unsuccessful attempts at influencing the king to let him return, including showcasing his instruments on the wall of the city, he acquiesced to exile. He wrote his most famous poem, Elegy to Dania in which he chided Denmark for not appreciating his genius.

Illness, death, and investigations

Tycho suddenly contracted a bladder or kidney ailment after attending a banquet in Prague. He died eleven days later, on 24 October 1601, at the age of 54. According to Kepler's first-hand account, Tycho had refused to leave the banquet to relieve himself because it would have been a breach of etiquette. After he returned home, he was no longer able to urinate, except eventually in very small quantities and with excruciating pain. The night before he died, he suffered from a delirium during which he was frequently heard to exclaim that he hoped he would not seem to have lived in vain.

Before dying, he urged Kepler to finish the Rudolphine Tables and expressed the hope that he would do so by adopting Tycho's own planetary system, rather than that of the polymath Nicolaus Copernicus. It was reported that Tycho had written his own epitaph, "He lived like a sage and died like a fool." A contemporary physician attributed his death to a kidney stone, but no kidney stones were found during an autopsy performed after his body was exhumed in 1901. Modern medical assessment is that his death was more likely caused by either a burst bladder, prostatic hypertrophy, acute prostatitis, or prostate cancer, which led to urinary retention, overflow incontinence, and uremia.

Investigations in the 1990s suggested that Tycho may not have died from urinary problems, but instead from mercury poisoning. It was speculated that he had been intentionally poisoned. The two main suspects were his assistant, Johannes Kepler, whose motives would be to gain access to Tycho's laboratory and chemicals, and his cousin, Erik Brahe, at the order of friend-turned-enemy Christian IV, because of rumors that Tycho had had an affair with Christian's mother.

In February 2010, the Prague city authorities approved a request by Danish scientists to exhume the remains, and in November 2010 a group of Czech and Danish scientists from Aarhus University collected bone, hair and clothing samples for analysis. The scientists, led by Jens Vellev, analyzed Tycho's beard hair once again. The team reported in November 2012 that there was not enough mercury present to substantiate murder, and there were no lethal levels of any poisons present. The team's conclusion was that "it is impossible that Tycho Brahe could have been murdered".

The findings were confirmed by scientists from the University of Rostock, who examined a sample of Tycho's beard hairs that had been taken in 1901. Although traces of mercury were found, these were present only in the outer scales. Therefore, mercury poisoning as the cause of death was ruled out. The study suggests that the accumulation of mercury may have come from the "precipitation of mercury dust from the air during [Tycho's] long-term alchemistic activities".

Career: observing the heavens

Observational astronomy

Tycho's view of science was driven by his passion for accurate observations, and the quest for improved instruments of measurement drove his life's work. Tycho was the last major astronomer to work without the aid of a telescope, soon to be turned skyward by Galileo Galilei and others. Given the limitations of the naked eye for making accurate observations, he devoted many of his efforts to improving the accuracy of the existing types of instrument – the sextant and the quadrant. He designed larger versions of these instruments, which allowed him to achieve much higher accuracy. Because of the accuracy of his instruments, he quickly realized the influence of wind and the movement of buildings, and instead opted to mount his instruments underground directly on the bedrock.

Tycho's observations of stellar and planetary positions were noteworthy both for their accuracy and quantity. With an accuracy approaching one arcminute, his celestial positions were much more accurate than those of any predecessor or contemporary – about five times as accurate as the observations of Wilhelm of Hesse. Rawlins (1993:§B2) asserts of Tycho's Star Catalog D, "In it, Tycho achieved, on a mass scale, a precision far beyond that of earlier catalogers. Cat D represents an unprecedented confluence of skills: instrumental, observational, and computational, all of which combined to enable Tycho to place most of his hundreds of recorded stars to an accuracy of ordermag 1'!"

He aspired to a level of accuracy in his estimated positions of celestial bodies of being consistently within an arcminute of their real celestial locations, and also claimed to have achieved this level. But, in fact, many of the stellar positions in his star catalogues were less accurate than that. The median errors for the stellar positions in his final published catalog were about 1.5', indicating that only half of the entries were more accurate than that, with an overall mean error in each coordinate of around 2'.

Although the stellar observations as recorded in his observational logs were more accurate, varying from 32.3" to 48.8" for different instruments, systematic errors of as much as 3' were introduced into some of the stellar positions Tycho published in his star catalog – due, for instance, to his application of an erroneous ancient value of parallax and his neglect of polestar refraction. Incorrect transcription in the final published star catalogue, by scribes in Tycho's employ, was the source of even larger errors, sometimes by many degrees.

Instruments

Many of Tycho's observations and discoveries were done with the aid of various instruments, many of which he himself made. The process that went into creating and refining his devices was haphazard at first, but was critical in the advancement of his observations. He pioneered an early example while he was a student in Leipzig. While he was gazing at the stars he realized that he needed a better way to write down not just his observations but also the angles and descriptions as well. So, he pioneered the use of the observational. In this notebook, he made his observations and asked himself questions to try to answer later on. Tycho also made sketches of what he saw as well from comets to the motions of planets.

His astronomical instrument innovation continued after his schooling. When he gained access to his inheritance, he went straight to work creating brand new instruments to replace the ones he used as a student. Tycho created a quadrant that was thirty-nine centimeters in diameter and added a new type of sight to it called a pinnacidia, or light cutters as it is translated. This brand-new sight meant that the old pinhole style sight was rendered obsolete. When the sights of the pinnacidia were aligned in the correct manner the object that it is lined up with will look exactly the same from both ends. This instrument was kept still on a heavy-duty base and adjusted via a brass plumb line and thumb screws, all of which helped give Tycho Brahe more accurate measurements of the heavens.

There were times that the instruments Tycho made were for a specific purpose or an event that he was witness to. Such was the case in 1577 when he first started construction of what would be called Uraniborg. In that year a comet was spotted moving across the sky. During this period of time Tycho made many observations, and one of the instruments that he used to make his observations was called a brass azimuthal quadrant. At sixty-five centimeters in radius it was a large instrument built either in 1576 or 1577, just in time for Tycho to use it to observe the path and distance of the 1577 comet. This instrument helped him to accurately track the comet's path as it crossed the orbits of the Solar System.

A great many more instruments were constructed at Tycho Brahe's new manor on Hven called Uraniborg. It was a combination of a home, observatories and laboratory where he made some of his discoveries along with many of his instruments. Several of these instruments were very large, such as a steel azimuth quadrant equipped with a brass arc that was six feet (or 194 centimeters) in diameter. This and other instruments were placed in the two observatories attached to the manor.

The Tychonic cosmological model

Although Tycho admired Copernicus and was the first to teach his theory in Denmark, he was unable to reconcile Copernican theory with the basic laws of Aristotelian physics, which he believed to be foundational. He was critical of the observational data that Copernicus built his theory on, which he correctly considered to be inaccurate. Instead, Tycho proposed a "geo-heliocentric" system in which the Sun and Moon orbited the Earth, while the other planets orbited the Sun. His system had many of the observational and computational advantages of Copernicus' system. It provided a safe position for those astronomers who were dissatisfied with older models, but reluctant to accept heliocentrism.

It gained a following after 1616, when the Catholic Church declared the heliocentric model to be contrary to philosophy and Christian scripture, and only able to be discussed as a computational convenience. Tycho's system offered a major innovation in that it eliminated the idea of transparent rotating crystalline spheres to carry the planets in their orbits. Kepler and other Copernican astronomers, tried unsuccessfully to persuade Tycho to adopt the heliocentric model of the Solar System. To Tycho, the idea of a moving Earth was "in violation not only of all physical truth but also of the authority of Holy Scripture, which ought to be paramount."

Tycho held that the Earth was too sluggish and massive to be continuously in motion. According to the accepted Aristotelian physics of the time, the heavens, whose motions and cycles were continuous and unending, were made of aether, a substance not found on Earth, that caused objects to move in a circle. By contrast, objects on Earth seem to have motion only when moved, and the natural state of objects on its surface was rest. Tycho said the Earth was an inert body, not readily moved. He acknowledged that the rising and setting of the Sun and stars could be explained by a rotating Earth, as Copernicus had said, still:

such a fast motion could not belong to the earth, a body very heavy and dense and opaque, but rather belongs to the sky itself whose form and subtle and constant matter are better suited to a perpetual motion, however fast.

Tycho believed that, if the Earth did orbit the Sun, there should be an observable stellar parallax every six months (the stars' positions would change thanks to Earth's changing position). The lack of any stellar parallax was explained by the Copernican theory as being due to the stars' enormous distances from Earth. Tycho noted and attempted to measure the apparent relative sizes of the stars in the sky. He used geometry to show that the distance to the stars in the Copernican system would have to be 700 times greater than the distance from the Sun to Saturn and to be seen at these distances the stars would have to be gigantic, at least as big as the orbit of the Earth, and of course vastly larger than the Sun. Tycho said:

Lunar theory

Tycho's distinctive contributions to lunar theory include his discovery of the variation of the Moon's longitude. This represents the largest inequality of longitude after the equation of the center and the evection. He also discovered librations in the inclination of the plane of the lunar orbit, relative to the ecliptic (which is not a constant of about 5° as had been believed before him, but fluctuates through a range of over a quarter of a degree), and accompanying oscillations in the longitude of the lunar node. These represent perturbations in the Moon's ecliptic latitude. Tycho's lunar theory doubled the number of distinct lunar inequalities, relative to those anciently known, and reduced the discrepancies of lunar theory to about a fifth of their previous amounts. It was published posthumously by Kepler in 1602, and Kepler's own derivative form appears in Kepler's Rudolphine Tables of 1627.

Subsequent developments in astronomy

Kepler used Tycho's records of the motion of Mars to deduce laws of planetary motion, enabling calculation of astronomical tables with unprecedented accuracy (the Rudolphine Tables) and providing powerful support for a heliocentric model of the Solar System.

Galileo's 1610 telescopic discovery that Venus shows a full set of phases refuted the pure geocentric Ptolemaic model. After that it seems 17th-century astronomy mostly converted to geo-heliocentric planetary models that could explain these phases just as well as the heliocentric model could, but without the latter's disadvantage of the failure to detect any annual stellar parallax that Tycho and others regarded as refuting it.

The three main geo-heliocentric models were the Tychonic, the Capellan with just Mercury and Venus orbiting the Sun such as favoured by Francis Bacon, for example, and the extended Capellan model of Riccioli with Mars also orbiting the Sun whilst Saturn and Jupiter orbit the fixed Earth. The Tychonic model was probably the most popular, albeit probably in what was known as 'the semi-Tychonic' version with a daily rotating Earth. This model was advocated by Tycho's ex-assistant and disciple Longomontanus, in his 1622 Astronomia Danica, that was the intended completion of Tycho's planetary model with his observational data, and which was regarded as the canonical statement of the complete Tychonic planetary system. Longomontanus' work was published in several editions and used by many subsequent astronomers. Through him, the Tychonic system was adopted by astronomers as far away as China.

The ardent anti-heliocentric French astronomer Jean-Baptiste Morin devised a Tychonic planetary model with elliptical orbits published in 1650 in a simplified, Tychonic version of the Rudolphine Tables. Another geocentric French astronomer, Jacques du Chevreul, rejected Tycho's observations including his description of the heavens and the theory that Mars was below the Sun. Some acceptance of the Tychonic system persisted through the 17th century and in places until the early 18th century. It was supported after a 1633 decree about the Copernican controversy, by "a flood of pro-Tycho literature" of Jesuit origin. Among pro-Tycho Jesuits, Ignace Pardies declared in 1691 that it was still the commonly accepted system, and Francesco Blanchinus reiterated that as late as 1728.

Work in medicine, alchemy and astrology

Tycho worked in medicine and alchemy. He was influenced by the Swiss physician Paracelsus, who considered the human body to be directly affected by celestial bodies. Tycho used Paracelsus's ideas to connect empiricism and natural science, and religion and astrology. Using his herbal garden at Uraniborg, Tycho produced recipes for herbal medicines, and used them to treat fever and plague. His herbal medicines were in use until the end of the 19th century.

The expression Tycho Brahe days referred to "unlucky days" that were featured in almanacs from the 1700s onwards, but which have no direct connection to Tycho or his work. Whether because Tycho realized that astrology was not an empirical science, or because he feared religious repercussions, he did not publicise his own astrological work. For example, two of his more astrological treatises, one on weather predictions and an almanac, were published in the names of his assistants, in spite of the fact that he worked on them personally. Some scholars have argued that he lost faith in horoscope astrology over the course of his career, and others that he simply changed his public communication on the topic as he realized that connections with astrology could influence the reception of his empirical astronomical work.

Legacy

Biographies

The first biography of Tycho, which was also the first full-length biography of any scientist, was written by Gassendi in 1654. In 1779, Tycho de Hoffmann wrote of Tycho's life in his history of the Brahe family. In 1913, Johann Dreyer published Tycho's collected works, facilitating further research. Early modern scholarship on Tycho tended to see the shortcomings of his astronomical model, painting him as a mysticist reluctant to accept Copernicanism, and valuing mostly his observations that allowed Kepler to formulate his laws of planetary movement. Especially in Danish scholarship, Tycho was depicted as a mediocre scholar and a traitor to the nation – perhaps because of the important role in Danish historiography of Christian IV as a warrior king.

In the second half of the 20th century, scholars began reevaluating his significance, and studies by Kristian Peder Moesgaard, Owen Gingerich, Robert Westman, Victor E. Thoren, John R. Christianson and C. Doris Hellman focused on his contributions to science, and demonstrated that while he admired Copernicus he was simply unable to reconcile his basic theory of physics with the Copernican view. Christianson's work showed the influence of Tycho's Uraniborg as a training center for scientists who after studying with Tycho went on to make contributions in various scientific fields.

Scientific legacy

Although Tycho's planetary model was soon discredited, his astronomical observations were an essential contribution to the Scientific Revolution. The traditional view of Tycho is that he was primarily an empiricist who set new standards for precise and objective measurements. This appraisal originated in Gassendi's 1654 biography, Tychonis Brahe, equitis Dani, astronomorum coryphaei, vita. It was furthered by Dreyer's biography in 1890, which was long the most influential work on Tycho. According to historian of science Helge Kragh, this assessment grew out of Gassendi's opposition to Aristotelianism and Cartesianism, and fails to account for the diversity of Tycho's activities.

Tycho was the last major astronomer before the invention of the telescope and has been described as the greatest pre-telescopic astronomer.

The Tycho Brahe Prize, inaugurated in 2008, is awarded annually by the European Astronomical Society in recognition of the pioneering development or exploitation of European astronomical instrumentation, or major discoveries based largely on such instruments.

Cultural legacy

Tycho's discovery of the new star was the inspiration for Edgar Allan Poe's poem "Al Aaraaf". In 1998, Sky & Telescope magazine published an article by Donald Olson, Marilynn S. Olson and Russell L. Doescher arguing, in part, that Tycho's supernova was also the same "star that's westward from the pole" in Shakespeare's Hamlet.

Tycho is directly referenced in Sarah Williams' poem The Old Astronomer: "Reach me down my Tycho Brahé, – I would know him when we meet". Though, the poem's oft quoted line comes later: "Though my soul may set in darkness, it will rise in perfect light; / I have loved the stars too fondly to be fearful of the night."

Alfred Noyes in his Watchers of the Sky (the first part of The Torch-bearers of 1922) included a long biographical poem in honour of Brahe, elaborating on the known history in a highly romantic and imaginative way.

The lunar crater Tycho is named in his honour, as is the crater Tycho Brahe on Mars and the minor planet 1677 Tycho Brahe in the asteroid belt. The bright supernova, SN 1572, is also known as Tycho's Nova and the Tycho Brahe Planetarium in Copenhagen is also named after him, as is the palm genus Brahea. In 2015, the planet Brahe was named after him as part of the NameExoWorlds campaign.

Brahe Rock in Antarctica is named after Tycho Brahe.

In The Expanse (novel series) and The Expanse (TV series) "Tycho" is the name of a company known for its large-scale building projects all around the Solar System. The company has their own space station named "Tycho Station".

In the 1996 video game Descent II, the players' 7th destination planet is named Tycho Brahe.

Author Jerry Holkins' comic alter ego and online handle for Penny Arcade is named after the astronomer Tycho Brahe.

Works (selection)

Tychonis Brahe Astronomiae Instauratae Progymnasmata (Introduction to the New Astronomy) (Prague, 1602/03; Frankfurt, 1610)

De Mundi Aetherei Recentioribus Phaenomenis Liber Secundus (Second Book About Recent Phenomena in the Celestial World) (Uraniborg, 1588; Prague, 1603; Frankfurt, 1610)

[Opere. Carteggi] (in Latin). København: G.E.C. Gad. 1876–1886.