Instruct: Given a question, retrieve documents that answer the question.
Query: Who were Galileo's contemporaries?
Jesuit astronomers, experts both in Church teachings, science, and in natural philosophy, were at first skeptical and hostile to the new ideas; however, within a year or two the availability of good telescopes enabled them to repeat the observations. In 1611, Galileo visited the Collegium Romanum in Rome, where the Jesuit astronomers by that time had repeated his observations. Christoph Grienberger, one of the Jesuit scholars on the faculty, sympathized with Galileo's theories, but was asked to defend the Aristotelian viewpoint by Claudio Acquaviva, the Father General of the Jesuits. Not all of Galileo's claims were completely accepted: Christopher Clavius, the most distinguished astronomer of his age, never was reconciled to the idea of mountains on the Moon, and outside the collegium many still disputed the reality of the observations. In a letter to Kepler of August 1610, Galileo complained that some of the philosophers who opposed his discoveries had refused even to look through a telescope:
The thermoscope, or Galileo thermometer, was constructed by Galileo Galilei in 1607. In 1643, Evangelista Torricelli invented the mercury barometer. Blaise Pascal (in 1648) rediscovered that atmospheric pressure decreases with height, and deduced that there is a vacuum above the atmosphere.
Many argue that the ideas characterizing the Renaissance had their origin in late 13th-century Florence, in particular with the writings of Dante Alighieri (1265–1321) and Petrarch (1304–1374), as well as the paintings of Giotto di Bondone (1267–1337). Some writers date the Renaissance quite precisely; one proposed starting point is 1401, when the rival geniuses Lorenzo Ghiberti and Filippo Brunelleschi competed for the contract to build the bronze doors for the Baptistery of the Florence Cathedral (Ghiberti won). Others see more general competition between artists and polymaths such as Brunelleschi, Ghiberti, Donatello, and Masaccio for artistic commissions as sparking the creativity of the Renaissance. Yet it remains much debated why the Renaissance began in Italy, and why it began when it did. Accordingly, several theories have been put forward to explain its origins.
Andreas Vesalius (1514-1564), a Flemish anatomist, was at first a "Galenist" at the University of Paris. When he moved to Italy and entered the University of Padua, he began dissecting human bodies. He studied many details of human anatomy and found that Galen made some anatomical mistakes. For example, Galen wrote that the sternum has seven segments, but Vesalius found it has three segments. Galen wrote that the bone of the arm is the longest bone in the human body, but Vesalius found that the bone of the thigh is actually the longest bone in human body. At age 25 Vesalius realized that the anatomical knowledge of Galen was derived from animal anatomy and therefore Galen had never dissected a human body.
Many of the scholars in the Platonic Academy sought to clarify and explain Plato's ideas. Already in the 3rd century BC, we hear of a commentary to Plato's "Timaeus" being written by Crantor of Soli; and in the 1st century AD a commentary on Plato's "Republic" was written by Onasander. By the 2nd century the Middle Platonists were producing paraphrases and summaries of Plato's thought. Thus we have Albinus, who wrote an introduction to Plato's works, and Alcinous and Apuleius who both wrote manuals of Platonism. From the physician Galen we have fragments of a commentary on the "Timaeus". Already though the influence of Aristotle was being felt on the popular Platonism of the day, and we have the figure of Atticus (c. 175) who opposed the eclecticism which had invaded the school and contested the theories of Aristotle as an aberration from Plato.
Hypatia (born 350–370; died 415 AD) was a Hellenistic Neoplatonist philosopher, astronomer, and mathematician, who lived in Alexandria, Egypt, then part of the Eastern Roman Empire. She was a prominent thinker of the Neoplatonic school in Alexandria, where she taught philosophy and astronomy. She is the first female mathematician whose life is reasonably well recorded. Hypatia was renowned in her own lifetime as a great teacher and a wise counselor. She is known to have written a commentary on Diophantus's thirteen-volume "Arithmetica", which may survive in part, having been interpolated into Diophantus's original text, and another commentary on Apollonius of Perga's treatise on conic sections, which has not survived. Many modern scholars also believe that Hypatia may have edited the surviving text of Ptolemy's "Almagest", based on the title of her father Theon's commentary on Book III of the "Almagest".
Following the first wave of Arabic interest during the Renaissance of the 12th century, which saw numerous Arabic texts being translated into Latin, there was a 'second wave' of interest in the study of Arabic literature, Arabic science and Islamic philosophy in 16th-century France and 17th-century England.
Together with the development of the Franco-Ottoman alliance, cultural and scientific exchanges between France and the Ottoman Empire flourished. French scholars such as Guillaume Postel or Pierre Belon were able to travel to Asia Minor and the Middle East to collect information.
Scientific exchange is thought to have occurred, as numerous works in Arabic, especially pertaining to astronomy were brought back, annotated and studied by scolars such as Guillaume Postel. Transmission of scientific knowledge, such as the Tusi-couple, may have occurred on such occasions, at the time when Copernicus was establishing his own astronomical theories.
The Galilean moons are the four largest moons of Jupiter—Io, Europa, Ganymede, and Callisto. They were first seen by Galileo Galilei in January 1610, and recognized by him as satellites of Jupiter in March 1610. They were the first objects found to orbit another planet. Their names derive from the lovers of Zeus. They are among the largest objects in the Solar System with the exception of the Sun and the eight planets, with a radius larger than any of the dwarf planets. Ganymede is the largest moon in the Solar System, and is even bigger than the planet Mercury, though only around half as massive. The three inner moons—Io, Europa, and Ganymede—are in a 4:2:1 orbital resonance with each other. Because of their much smaller size, and therefore weaker self-gravitation, all of Jupiter's remaining moons have irregular forms rather than a spherical shape.
Stefan of Pise translated into Latin around 1127 an Arab manual of medical theory. The method of algorism for performing arithmetic with Indian-Arabic numerals was developed by the Persian al-Khwarizmi in the 9th century, and introduced in Europe by Leonardo Fibonacci (1170–1250). A translation by Robert of Chester of the "Algebra" by al-Kharizmi is known as early as 1145. Ibn al-Haytham (Alhazen, 980–1037) compiled treatises on optical sciences, which were used as references by Newton and Descartes. Medical sciences were also highly developed in Islam as testified by the Crusaders, who relied on Arab doctors on numerous occasions. Joinville reports he was saved in 1250 by a “Saracen” doctor.
Ultimately, it was Newton's friend, editor and publisher, Edmond Halley, who, in his 1705 "Synopsis of the Astronomy of Comets", used Newton's new laws to calculate the gravitational effects of Jupiter and Saturn on cometary orbits. Having compiled a list of 24 comet observations, he calculated that the orbital elements of a second comet that had appeared in 1682 were nearly the same as those of two comets that had appeared in 1531 (observed by Petrus Apianus) and 1607 (observed by Johannes Kepler). Halley thus concluded that all three comets were, in fact, the same object returning about every 76 years, a period that has since been found to vary between 74–79 years. After a rough estimate of the perturbations the comet would sustain from the gravitational attraction of the planets, he predicted its return for 1758. While he had personally observed the comet around perihelion in September 1682, Halley died in 1742 before he could observe its predicted return.
Notable German physicists before the 20th century include Hermann von Helmholtz, Joseph von Fraunhofer and Gabriel Daniel Fahrenheit, among others. Albert Einstein introduced the special relativity and general relativity theories for light and gravity in 1905 and 1915 respectively. Along with Max Planck, he was instrumental in the introduction of quantum mechanics, in which Werner Heisenberg and Max Born later made major contributions. Wilhelm Röntgen discovered X-rays. Otto Hahn was a pioneer in the fields of radiochemistry and discovered nuclear fission, while Ferdinand Cohn and Robert Koch were founders of microbiology. Numerous mathematicians were born in Germany, including Carl Friedrich Gauss, David Hilbert, Bernhard Riemann, Gottfried Leibniz, Karl Weierstrass, Hermann Weyl, Felix Klein and Emmy Noether.
Adelard of Bath (; 1080 1152 AD) was a 12th-century English natural philosopher. He is known both for his original works and for translating many important Arabic and Greek scientific works of astrology, astronomy, philosophy and mathematics into Latin from Arabic versions, which were then introduced to Western Europe. He is known as one of the first to introduce the Arabic numeral system to Europe. He stands at the convergence of three intellectual schools: the traditional learning of French schools, the Greek culture of Southern Italy, and the Arabic science of the East.
Economic historian Joel Mokyr has argued that Islamic philosopher al-Ghazali (1058–1111) "was a key figure in the decline in Islamic science", as his works contributed to rising mysticism and occasionalism in the Islamic world. Against this view, Saliba (2007) has given a number of examples especially of astronomical research flourishing after the time of al-Ghazali.
Halley at first agreed with the longtime consensus that each comet was a different entity making a single visit to the solar system. In 1705, he applied Newton's method to 23 cometary apparitions that had occurred between 1337 and 1698. Halley noted that three of these, the comets of 1531, 1607, and 1682, had very similar orbital elements, and he was further able to account for the slight differences in their orbits in terms of gravitational perturbation by Jupiter and Saturn. Confident that these three apparitions had been three appearances of the same comet, he predicted that it would appear again in 1758–9. (Earlier, Robert Hooke had identified the comet of 1664 with that of 1618, while Giovanni Domenico Cassini had suspected the identity of the comets of 1577, 1665, and 1680. Both were incorrect.) Halley's predicted return date was later refined by a team of three French mathematicians: Alexis Clairaut, Joseph Lalande, and Nicole-Reine Lepaute, who predicted the date of the comet's 1759 perihelion to within one month's accuracy. Halley died before the comet's return; when it returned as predicted, it became known as Halley's Comet (with the latter-day designation of 1P/Halley). The comet next appears in 2061.
Perhaps inspired by Kepler (and quoting Kepler's third law of planetary motion), Jonathan Swift's satire "Gulliver's Travels" (1726) refers to two moons in Part 3, Chapter 3 (the "Voyage to Laputa"), in which Laputa's astronomers are described as having discovered two satellites of Mars orbiting at distances of 3 and 5 Martian diameters with periods of 10 and 21.5 hours. Phobos and Deimos (both found in 1877, more than a century after Swift's novel) have actual orbital distances of 1.4 and 3.5 Martian diameters, and their respective orbital periods are 7.66 and 30.35 hours. In the 20th century, V. G. Perminov, a spacecraft designer of early Soviet Mars and Venus spacecraft, speculated Swift found and deciphered records that Martians left on Earth. However, the view of most astronomers is that Swift was simply employing a common argument of the time, that as the inner planets Venus and Mercury had no satellites, Earth had one and Jupiter had four (known at the time), that Mars by analogy must have two. Furthermore, as they had not yet been discovered, it was reasoned that they must be small and close to Mars. This would lead Swift to making a roughly accurate estimate of their orbital distances and revolution periods. In addition Swift could have been helped in his calculations by his friend, the mathematician John Arbuthnot. 
Voltaire's 1752 short story "Micromégas", about an alien visitor to Earth, also refers to two moons of Mars. Voltaire was presumably influenced by Swift. In recognition of these 'predictions', two craters on Deimos are named Swift and Voltaire, while on Phobos there is one named regio, "Laputa Regio", and one named planitia, "Lagado Planitia", both of which are named after places in "Gulliver's Travels" (the fictional Laputa, a flying island, and Lagado, imaginary capital of the fictional nation Balnibarbi). Many of the craters on Phobos are also named after characters in "Gulliver's Travels".
Johann Carl Friedrich Gauss (; ; ; (30 April 177723 February 1855) was a German mathematician and physicist who made significant contributions to many fields in mathematics and sciences. Sometimes referred to as the "Princeps mathematicorum" () and "the greatest mathematician since antiquity", Gauss had an exceptional influence in many fields of mathematics and science, and is ranked among history's most influential mathematicians.
Galileo Rock is a chestnut horse with a broad white blaze and three white socks bred in Ireland by Rockfield Farm. He was sired by Galileo the winner of the 2001 Derby who went on to become an outstanding breeding stallion, winning the title of champion sire on four occasions. Galileo's other progeny include Rip Van Winkle, Nathaniel, Cape Blanco, New Approach and Frankel. His dam Grecian Bride came from a family established at the Ballymacoll Stud: her grandmother Edinburgh is also the direct female-line ancestor of Golan and North Light. Grecian Bride has also produced Saddler's Rock, a leading stayer who won both the Doncaster Cup in 2011 Goodwood Cup in 2012.
From the first scientific investigations of the pendulum around 1602 by Galileo Galilei, the regular motion of pendulums was used for timekeeping, and was the world's most accurate timekeeping technology until the 1930s. The pendulum clock invented by Christian Huygens in 1658 became the world's standard timekeeper, used in homes and offices for 270 years, and achieved accuracy of about one second per year before it was superseded as a time standard by the quartz clock in the 1930s. Pendulums are also used in scientific instruments such as accelerometers and seismometers. Historically they were used as gravimeters to measure the acceleration of gravity in geophysical surveys, and even as a standard of length. The word "pendulum" is new Latin, from the Latin "pendulus", meaning 'hanging'.
Hipparchus is credited with the invention or improvement of several astronomical instruments, which were used for a long time for naked-eye observations. According to Synesius of Ptolemais (4th century) he made the first "astrolabion": this may have been an armillary sphere (which Ptolemy however says he constructed, in "Almagest" V.1); or the predecessor of the planar instrument called astrolabe (also mentioned by Theon of Alexandria). With an astrolabe Hipparchus was the first to be able to measure the geographical latitude and time by observing fixed stars. Previously this was done at daytime by measuring the shadow cast by a gnomon, by recording the length of the longest day of the year or with the portable instrument known as a "scaphe".
The Persian polymath Avicenna claimed to have observed Venus as a spot on the Sun. This is possible, as there was a transit on May 24, 1032, but Avicenna did not give the date of his observation, and modern scholars have questioned whether he could have observed the transit from his location at that time; he may have mistaken a sunspot for Venus. He used his transit observation to help establish that Venus was, at least sometimes, below the Sun in Ptolemaic cosmology, i.e. the sphere of Venus comes before the sphere of the Sun when moving out from the Earth in the prevailing geocentric model.
Ghirlandaio is credited as the teacher of Michelangelo. Francesco Granacci is another among his pupils. According to Vasari, these two were sent by Ghirlandaio to the Medici Academy, when Lorenzo de' Medici requested his two best pupils. Although Michelangelo regarded himself primarily as a sculptor, in the 16th century he was to follow his master as a painter of frescos, at the Sistine Chapel.
There were a number of Florentines in Rome who were connected with Urban VIII or his nephew Cardinal Francesco Barberini - Rinuccini's brother Giovanni Battista became lieutenant to Cardinal Barberini. Galileo was in frequent correspondence with a number of them, including Mario Guiducci, Francesco Stelluti and Benedetto Castelli, as well as both Rinuccini brothers. The new Pope was friendly towards Galileo and many of his ideas, and his election seemed an excellent opportunity to take a more assertive line on astronomy than had been possible since the Roman Inquisition had proscribed heliocentrism in 1616. It was important for Galileo to carefully judge the political mood in Rome before publishing anything controversial and Tommaso Rinuccini was an important informant on whom he relied.
Three of Galileo's five siblings survived infancy. The youngest, Michelangelo (or Michelagnolo), also became a noted lutenist and composer although he contributed to financial burdens during Galileo's young adulthood. Michelangelo was unable to contribute his fair share of their father's promised dowries to their brothers-in-law, who would later attempt to seek legal remedies for payments due. Michelangelo would also occasionally have to borrow funds from Galileo to support his musical endeavours and excursions. These financial burdens may have contributed to Galileo's early desire to develop inventions that would bring him additional income.
Fabri was a highly respected scientist among his contemporaries. He was elected to the Accademia del Cimento in 1657, the year the Academy was founded.Leibniz placed him with Galileo, Torricelli, Steno and Borelli for his work on elasticity and the theory of vibrations, and alone with Galileo for his efforts to 'rationalise experimental kinematics'. Mersenne rated him 'a veritable giant in science'
In this most famous example cited by critics of the Catholic Church's "posture towards science", Galileo Galilei was denounced in 1633 for his work on the heliocentric model of the solar system, previously proposed by the Polish clergyman and intellectual Nicolaus Copernicus. Copernicus's work had been suppressed de facto by the Church, but Catholic authorities were generally tolerant of discussion of the hypothesis as long as it was portrayed only as a useful mathematical fiction, and not descriptive of reality. Galileo, by contrast, argued from his unprecedented observations of the solar system that the heliocentric system was not merely an abstract model for calculating planetary motions, but actually corresponded to physical reality – that is, he insisted the planets really do orbit the Sun. After years of telescopic observation, consultations with the Popes, and verbal and written discussions with astronomers and clerics, a trial was convened by the Tribunal of the Roman and Universal Inquisition. Galileo was found "vehemently suspect of heresy" (not "guilty of heresy," as is frequently misreported), placed under house arrest, and all of his works, including any future writings, were banned. Galileo had been threatened with torture and other Catholic scientists fell silent on the issue. Galileo's great contemporary René Descartes stopped publishing in France and went to Sweden. According to Polish-British historian of science Jacob Bronowski: