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Geminiano Montanari (June 1 1633-October 13 1687) was an
ItalianItaly , officially the Italian Republic , is a country located on the Italian Peninsula in Southern Europe and on the two largest islands in the Mediterranean Sea, Sicily and Sardinia. Italy shares its northern, Alpine boundary with France, Switzerland, Austria and Slovenia...
astronomerAstronomy is the scientific study of celestial objects and phenomena that originate outside the Earth's atmosphere...
,
lensA lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens is a lens consisting of a single optical element...
-maker, and proponent of the experimental approach to science.
He is best known for his observation, made around 1667, that the second brightest star (called
AlgolAlgol , known colloquially as the Demon Star, is a bright star in the constellation Perseus. It is one of the best known eclipsing binaries, the first such star to be discovered, and also one of the first variable stars to be discovered...
in
ArabicArabic is a Central Semitic language, thus related to and classified alongside other Semitic languages such as Hebrew and the Neo-Aramaic languages. In terms of speakers, the Arabic macrolanguage is the largest member of the Semitic language family. It is spoken by more than 280 million people as...
) in the constellation of
PerseusPerseus is a constellation in the northern sky, named after the Greek hero Perseus. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations defined by the International Astronomical Union...
varied in brightness. It is likely that others had observed this effect before, but Montanari was the first named astronomer to record it.
thumb
Geminiano Montanari (June 1 1633-October 13 1687) was an
ItalianItaly , officially the Italian Republic , is a country located on the Italian Peninsula in Southern Europe and on the two largest islands in the Mediterranean Sea, Sicily and Sardinia. Italy shares its northern, Alpine boundary with France, Switzerland, Austria and Slovenia...
astronomerAstronomy is the scientific study of celestial objects and phenomena that originate outside the Earth's atmosphere...
,
lensA lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens is a lens consisting of a single optical element...
-maker, and proponent of the experimental approach to science.
He is best known for his observation, made around 1667, that the second brightest star (called
AlgolAlgol , known colloquially as the Demon Star, is a bright star in the constellation Perseus. It is one of the best known eclipsing binaries, the first such star to be discovered, and also one of the first variable stars to be discovered...
in
ArabicArabic is a Central Semitic language, thus related to and classified alongside other Semitic languages such as Hebrew and the Neo-Aramaic languages. In terms of speakers, the Arabic macrolanguage is the largest member of the Semitic language family. It is spoken by more than 280 million people as...
) in the constellation of
PerseusPerseus is a constellation in the northern sky, named after the Greek hero Perseus. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations defined by the International Astronomical Union...
varied in brightness. It is likely that others had observed this effect before, but Montanari was the first named astronomer to record it. The star's names in Arabic,
HebrewHebrew is a Semitic language of the Afro-Asiatic language family. Culturally, it is considered a Jewish language. Hebrew in its modern form is spoken by more than seven million people in Israel while Classical Hebrew has been used for prayer or study in Jewish communities around the world for over...
and other languages, all of which have a meaning of "
ghoulA ghoul is a mythological monster from ancient Arabian folklore that dwells in burial grounds and other uninhabited places. The English word comes from the Arabic name for the creature: الغول al-ghūl, which literally means "demon"...
" or "
demonIn religion, folklore, and mythology a demon is a supernatural being that is generally described as a malevolent spirit. In Christian terms demons are generally understood as fallen angels, formerly of God. A demon is frequently depicted as a force that may be conjured and insecurely controlled...
", imply that its unusual behaviour had long been recognised.
Montanari was born in
ModenaModena is a city and a comune on the south side of the Po valley, in the Province of Modena in the Emilia-Romagna region of Italy....
, studied
lawLaw is a system of rules, usually enforced through a set of institutions. It shapes politics, economics and society in numerous ways and serves as a primary social mediator of relations between people. Contract law regulates everything from buying a bus ticket to trading on derivatives markets...
in
FlorenceFlorence is the capital city of the Italian region of Tuscany and of the province of Florence...
, and graduated from the
University of SalzburgThe University of Salzburg, or Paris Lodron University after its founder, the Prince Archbishop Paris Lodron, is located in the Austrian city of Salzburg, Salzburgerland, home of Mozart. It is divided into 4 faculties: catholic theology, law, sociology and natural science.Founded in 1622, it today...
. In 1662 or 1663 he moved to
BolognaBologna is the capital city of Emilia-Romagna, in the Po Valley of northern Italy...
, where he drew an accurate map of the
MoonThe Moon is Earth's only natural satellite and the fifth largest satellite in the Solar System. The average centre-to-centre distance from the Earth to the Moon is , about thirty times the diameter of the Earth. The common centre of mass of the system is located at about —a quarter the Earth's...
using an
ocular micrometerAn ocular micrometer is a glass disk that fits in a microscope eyepiece that has a ruled scale, which is used to measure the size of magnified objects. The physical length of the marks on the scale depend on the degree of magnification....
of his own making. He also made observations on capillarity and other problems in
staticsStatics is the branch of mechanics concerned with the analysis of loads on physical systems in static equilibrium, that is, in a state where the relative positions of subsystems do not vary over time, or where components and structures are at a constant velocity...
, and suggested that the
viscosityViscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or extensional stress. In everyday terms , viscosity is "thickness." Thus, water is "thin," having a lower viscosity, while honey is "thick," having a higher viscosity...
of a liquid depended on the shape of its
moleculeA molecule is defined as an electrically neutral group of at least two atoms in a definite arrangement held together by very strong chemical bonds. Molecules are distinguished from polyatomic ions in this strict sense...
s. In 1669 he succeeded
Giovanni CassiniThis article is about the Italian-born astronomer. For his French-born great-grandson, see Jean-Dominique Cassini.Giovanni Domenico Cassini was an Italian/French mathematician, astronomer, engineer, and astrologer...
as astronomy teacher at the
observatoryAn observatory is a location used for observing terrestrial and/or celestial events. Astronomy, climatology/meteorology, geology, oceanography and volcanology are examples of disciplines for which observatories have been constructed...
of Panzano, near Modena, where one of his duties was to compile an astrological
almanacAn almanac is an annual publication containing tabular information in a particular field or fields often arranged according to the calendar...
. He did so in 1665, but perpetrated a deliberate hoax by writing the almanac entirely at random, to show that predictions made by chance were as likely to be fulfilled as those made by astrology. In the period shortly after
Galileo GalileiGalileo Galilei was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations, and support for Copernicanism...
, experimentalists like Montanari were engaged in a battle against the more mystical views of scientists such as Donato Rossetti.
On 21 March 1676 Montanari reported a sighting of a
cometA comet is a Small Solar System Body that has coma and is bigger than a meteoroid. When close enough to the Sun, a comet exhibits a visible coma , and sometimes a tail, both because of the effects of solar radiation upon the comet's nucleus...
to Edmund Halley.
In 1679 Montanari moved to a teaching post in
PaduaPadua is a city in the Veneto, northern Italy. It is the capital of the province of Padua and the economic and communications hub of the area. Padua's population is 212,500 . The city is sometimes included, with Venice , in the Padua-Venice Metropolitan Area, having a population of c...
, but almost all records of this period of his life have been lost. A letter survives from 1682 recording a sighting of Halley's Comet. He also wrote on
economicsEconomics is the social science that studies the production, distribution, and consumption of goods and services. The term economics comes from the Ancient Greek from + , hence "rules of the house"...
, observing that demand for a particular commodity was fixed, and making comments on coinage and the value of money (1683).
A
craterMontanari is a lunar crater. It is located to the west-southwest of the prominent ray crater Tycho, and is attached to the southern rim of the walled plain Wilhelm...
on the Moon, at 45.8S, 20.6W, is named after him.
Publications
- De motionibus naturalibus a gravitate pendentibus (1667)
- Pensieri fisico-matematici (1667)
- La Livella Diottrica (The Spirit Level) (1674)
- Trattato mercantile delle monete (1680)
External links