Galileo Timeline Galileo Timeline
his timeline provides a detailed chronology of Galileo's life. Two types of links are provided. Within the text, there are hyperlinks to longer texts and related resources. When a year is highlighted, it is l
inked to the General European Timeline, which provides a broad overview of concurrent events in Europe.
Note: Dates before October 1582 are Julian; all others are on
the Gregorian Calendar.
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1562 July 5 Vincenzo Galilei of Florence marries Giulia
degli Ammannati of Pescia. They live in Pisa.
1564 Feb. 15 Galileo, their first child, is born.
Feb. 19 Galileo is baptized in the baptistry of the
cathedral of Pisa.
1573 May 8 Virginia Galilei is born.
1574 Vincenzo Galilei and his family move to
Florence.
1575 Dec. 18 Michelangelo Galilei is born.
1578 Oct. 7 Livia Galilei is born
1579 Galileo is at the monastery of Santa Maria di
Vallombrosa, where he considers joining the order.
July Galileo returns to his family in Florence.
1583 According to Vincenzo Viviani, Galileo's
first biographer, during his student days at
Pisa Galileo formulated the isochronism of the
pendulum while watching the oscillations of a
lamp in the cathedral of Pisa.
Galileo first studies Euclid's Elements--not at
the university, but in Florence under the
court mathematician Ostilio Ricci.
1585 He completes the fourth year of his studies
and returns to Florence without a degree.
1586 Galileo begins to work on certain problems in
physics, following Archimedes rather than
Aristotle. He invents a hydrostatic
balance(bilancetta).
1585-89 Gives private lessons in mathematics in
Florence and Siena.
1587 First voyage to Rome; meets Christoph Clavius
Applies for a lectureship of mathematics at
the University of Siena.
Finds certain propositions about centers of
gravity which go beyond the work of
Archimedes.
1588 (?) Vincenzo Galilei performs experiments on the
relationship between the tension and pitch of
strings. His son, Galileo, may have helped
him with these and surely was aware of them.
Galileo gives two public lectures at the Accademia
Fiorentina (Florentine Academy) about the
shape, location, and dimensions of hell as
described in Dante's Inferno.
Tries to obtain teaching positions at
the universities of Pisa, Siena, Padua, and
Bologna, and a lectureship in Florence. He
obtains a lectureship of mathematics at
the university of Pisa.
1589-1592 Teaches mathematical subjects at the
University of Pisa (salary 160 scudi per
year). Some tracts--lecture notes--written
during this period have survived. In On
motion Galileo uses the Archimedian
approach to motion: the speed of falling bodies
is proportional to their density, not their
weight as Aristotle had maintained.
According to Vincenzo Viviani Galileo
demonstrated his conclusions by dropping
weights from the leaning tower of Pisa. This
report has been doubted by historians.
1591 Vincenzo Galilei dies, leaving Galileo,
his oldest son, as the head of the family. He was
responsible to meet the terms of a large
endowment bestowed by his father on Virginia,
his sister, who had just been married to Luca
Landucci.
1592 Galileo obtains the chair of mathematics at
the university of Padua in the Venetian
Republic (salary 160 ducats per year), where
he remains until 1610. His initial contract
is for four years, renewable for two further
years. His inaugural lecture is on 7
December, and his first regular lecture on 13
December. His duties are to lecture on
geometry and astronomy. He gives private
lessons on Euclid, arithmetic, fortification,
surveying, cosmography, optics, and the use of
the sector.
1593 Puts together treatises on fortifications
and mechanics for his private students.
Invents a machine for raising water, a pump
driven by horses. In 1594 he receives a
patent on this design from the Venetian
Senate.
1595 Develops his explanation of the tides which
invokes the annual and diurnal motion of the
Earth. It appears that his preference for
the Copernican theory dates from this year.
1597 Invents a "geometric and military compass,"
a sector ("a mathematical instrument
consisting of two rulers connected at one end
by a joint and marked with several scales").
It was used to solve practical mathematical
problems. He taught its use to his private
students and wrote an instruction manual,
later published.
For the use of his students, he prepares a
Treatise on the Sphere, or Cosmographia.
1599 Enters a relationship with Marina Gamba
Employs a craftsman, Marc'Antonio Mazzoleni,
to make scientific instruments and produce the
sector of Galileo's invention, which are sold
to wealthy students along with his treatise
explaining its use.
He obtains a new, six-year contract,
retroactive to December 1598, with a salary of
320 ducats.
1600 Giordano Bruno is burned at the stake in
Rome.
Aug. 13 Marina Gamba gives birth to a daughter who
is baptized Virginia, who later takes the name
Maria Celeste.
1601 Jan Marriage of Galileo's sister, Livia, to Taddeo
Galetti. Galileo has promised a dowry of 1800
ducats--800 right away and 200 per year for
five years. His brother Michelangelo is to
pay half. Galileo borrows 600 ducats.
Aug. 18 Marina Gamba gives birth to a second daughter
who is baptized Livia, who later takes the name
Arcangela.
1602 Galileo experiments with the pendulum in
connection with natural accelerated motion.
His friend, the physician Santorio Santorio
uses the pendulum principle to invent a
pulsilogium, a hand-held pendulum with which
to take the pulse.
1603 He begins employing an amanuensis to copy
manuscript treatises which he sells to his
private students.
1604 Visits Mantua in an effort to obtain patronage
from the Duke of Mantua. The effort does
not bear fruit.
Experiments for the first time with
uniformly accelerated motion on a gently
sloping inclined plane, judging a ball's
positions after equal time intervals. These
experiments lead to the law of falling bodies,
although it takes Galileo three more years to
arrive at a mathematical demonstration of this
law.
Sept. His machine to lift water is tried in the
garden of the Contarini house in Padua.
Oct. 10 The new star (supernova) is first observed in
Padua.
Dec. 24 Galileo observes the new star for the first
time.
1605 Jan. Delivers three lectures on the new
star at the university of Padua. His argument
is that parallax measurements show that the
new star is beyond the Moon. It is therefore
in the heavens and thus change must be
admitted in the heavens.
Mar. Publishes Dialogue of Cecco di Ronchitti da
Bruzene with regard to the New Star, in Padua.
A second edition was published in Verona that same summer.
July The operations of the geometric and military
compass is printed. It is dedicated to Cosimo II
de' Medici.
1606 Summer Galileo publishes Considerations of
Alimberto Mauri on Some Places in the Discourse of
Lodovico Delle Colombe about the Star which appeared
in 1604.
1606/1607? Invents the thermoscope, a primative thermometer.
Writes a treatise on hydrostatics.
1607 Apr. Balthasar Capra publishes The use and
construction of the proportional compass in
Padua. This is a plagiarism of Galileo's book
on the sector. Galileo institues a legal process
that ended with the expulsion of Capra from
the university and the confiscation of all
unsold copies of the book. A German
mathematician named Simon Marius, Capra's
tutor until 1605, was implicated in the
affair.
Summer Galileo first investigates hydrostatics and the
strength of materials.
1607/1608 Further studies on motion. Discovery of the
parabolic path of projectiles.
1608 Galileo arms a lodestone belonging to his friend,
Sagredo and arranges for it to be bought by
Grand Duke Ferdinand I de' Medici. The 56-ounce
armed lodestone could lift 132 ounces of iron.
Summer Galileo is in Florence at the insistence of
the Grand Duchess Christina. Marriage of
Cosimo de' Medici. Galileo proposes the
lodestone as a device, or symbol marking
Cosimo's character and power.
1608 Oct. In The Hague, Hans Lipperhey requests a
patent on a spyglass.
1608/1609 Galileo constructs a hydrostatic balance.
Further studies of accelerated motion.
1609 Cosimo II de' Medici becomes Grand Duke of
Tuscany, following his father's death.
Johannes Kepler publishes his New Astronomy,
which contains his first two laws of planetary
motion.
May Galileo hears about the invention of devices
for seeing faraway things as though nearby
(telescope) in the Netherlands.
June Galileo duplicates the invention and makes a
three-powered telescope.
Aug. Thomas Harriot, observing near London, makes
a drawing of the Moon as seen through a 6-
powered telescope.
Through the connections of his friend Paolo
Sarpi, Galileo presents an eight-powered
telescope to the Venetian Senate. He is
rewarded by a doubling of his salary and life-
tenure at the University of Padua. He is
disappointed by the fine print.
Fall Continues his improvement of the telescope
and begins to make celestial observations
with the instrument.
Dec. Makes a series of observations of the Moon,
from 30 November to 19 December.
1610 Jan. On 7 January Galileo observes three bright
little stars near Jupiter; by 15 January he
has figured out that there are four
satellites of Jupiter.
Feb. While continuing his other observations,
Galileo maps some star formations.
Mar. Sidereus Nuncius, dedicated to Cosimo II,
Grand Duke of Tuscany, comes off the press in
Venice. The satellites of Jupiter are here
called the Medicean Stars, in honor of the
house of his prospective patron.
Apr. Johannes Kepler sends a letter in support of
Galileo's discoveries. The letter is published
in Prauge as Conversation with the
Sidereal Messenger. It is reprinted in
Florence a few months later.
Galileo travels to Pisa where he shows the
satellites of Jupiter to Grand Duke
Cosimo II de' Medici.
June Martin Horky publishes A very short excursion
against the Sidereal Messenger.
July Following negotiations, Galileo is appointed
"Chief Mathematician of the University of Pisa
and Philosopher and Mathematician to the Grand
Duke" of Tuscany. The appointment is for
life.
Galileo first observes the strange appearances
of Saturn.
Sept. Galileo moves from Padua to Florence.
Kepler verifies the existence of the
satellites of Jupiter (and publishes a tract
on them the next year).
Nov. John Wedderburn, a student of Galileo,
publishes, in Padua, a reply to Martin Horky's
tract.
The satellites of Jupiter are observed in
England by Thomas Harriot, in Provence by
Nicolas-Claude Fabri de Peiresc and
Joseph Gaultier de la Valette, and in Rome by
Christopher Clavius and the other Jesuit
mathematicians at the Collegio Romano.
Dec. Galileo verifies that Venus goes through
phases like the Moon. The phases of Venus
falsify the Ptolemaic System and prove that
Venus goes around the Sun, in conformance with
the Copernican System.
Thomas Harriot makes his first record of an
observation of sunspots.
1610 or 1611 Lodovico delle Colombe publishes Against
the Earth's Motion against Galileo's celestial
discoveries
1611 Francesco Sizzi publishes Dianoia
Astronomica, Optica, Physica against Galileo's
celestial discoveries.
Mar. Galileo arrives in Rome on 29 March.
Johannes Fabricius and his father, the
astronomer David Fabricius, begin their
observations of sunspots in Osteel in
northwestern Germany.
Mar. or Apr.
Christoph Scheiner, S.J. and his student
Johann Baptist Cysat, S.J., see spots on the
Sun but don't pursue the observation.
Apr. Upon the request of Cardinal Bellarmine,
the Jesuit mathematicians of the Collegio
Romano certify Galileo's celestial
discoveries, although they do not necessarily
agree with Galileo's interpretation of these
discoveries.
Galileo is inducted into the Lincean Academy,
at a banquet given by the academy's founder
and patron, Federico Cesi. At this occasion
the name telescope is first used.
May The Inquisition decides to check to see if
Galileo is mentioned in the proceedings
against the Aristotelian philosopher Cesare
Cremonini, Galileo's colleague and friendly
opponent at the University of Padua.
The mathematicians at the Collegio Romano
honor Galileo at a banquet. Odo van
Maelcote delivers a lecture on Galileo's
discoveries.
While in Rome, Galileo shows sunspots to some
of his friends.
June In Germany, Johannes Fabricius publishes
the first book on sunspots, Narration on
spots observed on the Sun and their apparent
rotation with the Sun (Wittenberg, 1611).
Aug Back in Florence, Galileo is drawn into a
dispute concerning the behavior of bodies in
water, taking the Archimedean position and
arguing against the position of Aristotle.
Sept. Kepler's Dioptrice published in Augsburg.
Oct. At a debate during a state dinner for two
visiting cardinals, Galileo repeats the
Archimedean arguments abouts bodies in water.
He is supported by Cardinal Maffeo Barberini
(later Pope Urban VIII), who became one of
Galileo's patrons at this time.
1612 Jan. A tract on sunspots, entitled Three letters
on solar spots, written by Christoph
Scheiner,is published in Augsburg under the
pseudonym "Apelles hiding behind the
painting."
May Galileo first letter on sunspots.
Aug. Galileo's second letter on sunspots.
Sept. Christoph Scheiner's second sunspot tract,
A more accurate discussion of sunspots and the
stars which move around Jupiter, again under
the pseudonym of Apelles.
Fall The Lincean Academy decides to publish
Galileo's letters on sunspots to Marc
Welser.
Dec. Galileo's third letter on sunspots.
1613 Mar. History and Demonstrations about Sunspots and
their Properties, containing the three letters
by Galileo is published by the Lincean Academy
in Rome. In about half the copies the two
tracts by Scheiner are reprinted.
Dec. Benedetto Castelli, professor of
Mathematics as the University of Pisa, and a
student of Galileo, defends the Copernican
theory to the Grand Duchess Dowager Christina
of Lorraine.
Upon hearing about this event, Galileo
composes a long letter to Castelli on his
views about the relationship between science
and Scriptures.
1614 Dec. Tommaso Caccini, a Dominican friar preaches
a sermon in Florence against Galileo and
mathematicians who subscribe to the Copernican
view which, Caccini avers, is heretical.
1615 Jan. Caccini's superior apologizes to Galileo in
writing.
Feb. A Dominican friar Niccolo Lorini, who
had earlier criticized Galileo's view in private
conversations, files a written complaint with
the Inquisition against Galileo's Copernican
views. He encloses a copy of Galileo's letter
to Castelli.
Mar. The Carmelite Friar Paolo Antonio Foscarini
published Letter on the Pythagorean and
Copernican Opinion of the Earth's Motion and
Sun's Rest and on the New Pythagorean World
System, in which are harmonized and reconciled
those passages of the Holy Scripture and those
theological propositions which could ever be
adduced against this opinion (Naples, 1615).
In this book, Foscarini argues that the
Copernican theory is compatible with
Scripture.
Caccini gives a deposition to the Roman
Inquisition.
Galileo writes a long letter defending his
views to Monsignor Piero Dini, a well
connected official in the Vatican.
Apr. Cardinal Bellarmine writes to Foscarini,
cautioning him to treat the Copernican theory
as a hypothesis only and includes Galileo in
his comments.
Summer Galileo writes his "Letter to the Grand
Duchess Christina," which is not printed
but circulates widely. (A Latin version is
published in the Netherlands in 1636.) This is
an enlarged version of his letter to Castelli
of Dec. 1613.
Dec. Galileo goes to Rome to defend his Copernican
ideas.
1616 Jan. Writes up his theory about the tides
which, he argues, proves that the earth moves.
He addresses this treatise to Cardinal
Alessandro Orsini.
Feb. A committee of consultants declares to the
Inquisition that the proposition that the
Sun is the center of the universe is absurd in
philosophy and formally heretical and that the
proposition that the Earth has an annual motion
is absurd in philosophy and at least erroneous
in theology.
On orders of the Pope Paul V, Cardinal
Bellarmine calls Galileo to his residence
and administers a warning not to hold or
defend the Copernican theory. An unsigned
transcript in the Inquisition file,
discovered in 1633, states that Galileo is
also forbidden to discuss the theory orally or
in writing.
Mar. The Congregation of the Index suspends
Copernicus's On the Revolutions
until corrected and bans Foscarini's book entirely,
Galileo is not mentioned in the decree.
Galileo has an audience with Pope Paul V, and
is assured by the Pope.
May Cardinal Bellarmine writes a letter to
Galileo certifying that Galileo had not been
on trial or condemned by the Inquisition.
June Galileo attacks the problem of determining
longitude at sea by means of eclipses of the
satellites of Jupiter.
After an oral dispute between Galileo and
Francesco Ingoli, it is agreed that Ingoli
will write out his argument and Galileo will
then reply in writing. Ingoli's tract,
Disputation on the place and stability of the
Earth, against the system of Copernicus, in
which he uses scriptural arguments against
Copernicus, is not printed. Because of the
decision by the Inquisition, Galileo does not
reply at this time.
1618 In October and November three different
comets appear, the third one very bright.
Orazio Grassi, a professor professor of
mathematics at the Collegio Romano, delivers
a public lecture on comets. A manuscript copy
of this lecture was sent to Galileo. The
lecture itself was published early in 1619
under the title On the Three Comets of the
Year MDCXVIII. An Astronomical Disputation
Presented Publicly in the Collegio Romano of
the Society of Jesus by one of the Fathers of
that same Society. At stake is the location
of these comets
1619 Jan/Feb Galileo's views on comets are requested by
many, among them Archduke Leopold of Austria.
He begins drafting a critique of the lecture
published by the Jesuit father at the Collegio
Romano.
June Mario Guiducci, a pupil of Galileo's, delivers
a lecture on the comets in which he argues
against the Jesuit interpretation of these
bodies. The lecture, written largely by
Galileo, is published under the title
Discourse on the Comets. By Mario Guiducci.
Delivered at the Florentine Academy during his
Term as Consul.
Oct. Under the pseudonym Lothario Sarsi, Orazio
Grassi counters with a tract entitled The
Astronomical Balance, on which the Opinions of
Galileo Galilei regarding Comets are weighed,
as well as those presented in the Florentine
Academy by Mario Guiducci and recently
published.
1620 May The Congregation of the Index issued the
corrections that must be made in
Copernicus's On the Revolutions
before it can be read.
June Mario Guiducci publishes a letter in which
he replies to Orazio Grassi's Astronomical
Balance.
Aug. Cardinal Maffeo Barberini sends Galileo a
poem entitled Adulatio Perniciosa, composed by
him in honor of Galileo.
1621 Jan. Galileo is elected Consul of the Accademia
Fiorentina.
Pope Paul V dies. He is succeeded by Gregory
XV, who dies in July 1623
Feb. Death of Grand Duke Cosimo II de' Medici. He is
succeeded by Ferdinand II (11 years old),
who will reign under the regency of his
grandmother, Christina of Lorraine, and his
mother, Marie Madeleine of Austria.
1622 Oct. Galileo sends the manuscript of The Assayer,
his reply to Grassi's Astronomical Balance, to
the Lincean Academy in Rome.
1623 Publication of Tommaso Campanella's Defense
of Galileo in Frankfurt.
Feb. The Roman censors give permission for The
Assayer to be printed.
Aug. Upon the death of Pope Gregory XV, Cardinal
Maffeo Barberini, a friend and patron of
Galileo, is elected Pope and takes the name
Urban VIII.
Oct. The Assayer, now dedicated to Pope Urban
VIII, is published in Rome under the auspices
of the Lincean Academy.
1624 Apr. Galileo goes to Rome where he has six
audiences with the Pope Urban VIII and also
has audience with a number of cardinals. The
Pope assured him that he could write about the
Copernican theory as long as he treated it as
a mathematical hypothesis.
In Rome Galileo shows a compound microscope
to members of the Lincean Academy.
Observations of a bee made with this
instrument by Francesco Stelluti were
published in 1630. Galileo then presented
this instrument to Cardinal Zollern for the
Duke of Bavaria.
June Galileo returns to Florence.
Sept. Galileo writes his "Letter to Ingoli," in
which he refutes Ingoli's Disputation of
1616. The letter is not printed but
circulates in manuscript.
Galileo begins revising his treatise on tides
(see 1616), which eventually results in his
Dialogue Concerning the Two Chief World
Systems (1632).
1624/25 A complaint against Galileo's Assayer is
lodged by a person unknown to us. The
complaint charges that the atomism espoused
in the book cannot be squared with the
official church doctrine regarding the
Eucharist, in which bread and wine are
"transubstantiated" into Christ's flesh and
blood. After an investigation by the
Inquisition, Galileo is cleared.
1626 Horatio Grassi publishes his reply to The
Assayer, a book entitled Ratio Ponderum Librae
ac Simbellae, in Paris.
1627 March Urban VIII bestows a pension of 60 scudi per
year on Vincenzio, the son of Galileo.
1629 Nov. Galileo once again takes up contact with
Spanish authorities about the determination of
longitude at sea by means of the satellites
of Jupiter.
Dec. Galileo becomes a grandfather, when Sestilia
Bocchineri, his son Vincenzio's wife since the
previous year, gives birth to a boy who is
given the name Galileo.
1630 Publication of Christoph Scheiner's Rosa
Ursina, the definitive work on sunspots for
over a century.
Death of Johannes Kepler.
Feb. Urban VIII bestows a pension of 40 scudi per
year on Galileo.
Apr. Galileo finishes his Dialogue Concerning the
Two Chief World Systems.
May/June Galileo is in Rome to clear his Dialogue with
the censors and make arrangements to have it
printed by the Lincean Academy. He
obtains conditional permission from the
Secretary of the Vatican
Summer An outbreak of the plague begins to disrupt
commerce and travel between cities.
Aug. Federico Cesi, the founder and patron of the
Lincean Academy, dies. This is the
end of his academy.
Fall Galileo sends the preface and ending of his
Dialogue to the Secretary of the Vatican for
corrections. He has now decided to print the
book in Florence.
1631 Spring Through Grand Duke Ferdinand II and his
ambassador in Rome, Galileo negotiates with
the Secretary of the Vatican about the
printing of the Dialogue. The final result is
that the preface and ending would be approved
in Rome while the remainder of the book would
be checked and approved by the Inquisition in
Florence.
1632 Feb. Printing of the Dialogue is completed.
Summer Further distribution of the Dialogo is
prohibited by Pope Urban VIII and a special
commission is appointed to examine the book.
Sept. Based on the report by the special commission,
Urban VIII refers the case to the
Inquisition. The Pope himself presides over
a meeting of the Inquisition in which the
decision is made to summon Galileo to Rome.
Oct. Galileo is notified of the summons by the
Inquisitor in Florence. He promises to obey
but requests that the trial be moved to
Florence.
Nov. At a meeting of the Inquisition presided
over by Urban VIII, Galileo's request is
refused. If necessary he will be forced to
obey the Inquisition's order.
Dec. The Florentine Inquisitor notifies Rome that
he had visited Galileo, who was ill in bed,
and that three physicians had signed a
statement that Galileo was too ill to undertake
the journey to Rome.
At a meeting again presided over by Urban
VIII himself, the Inquisition rejects
Galileo's excuse as a subterfuge and sends him
notification that if he does not come to Rome
voluntarily he will be arrested and brought to
Rome in chains.
1633 Jan. Galileo leaves Florence on 20 January and,
after two weeks quarantine (because of the
plague) just outside Rome, he arrives there on
13 February. As a special favor to Grand Duke
Ferdinand II de' Medici, the Pope allowes Galileo to
stay at the residence of the Tuscan
ambassador. Galileo is forbidden social
contacts.
Apr. Galileo is formally interrogated by the
Inquisition. From 12 to 30 April he is
detained in the building of the Inquisition
but in a comfortable apartment.
The consultants called in to examine Galileo's
Dialogue, file their reports.
A plea bargain is arranged whereby Galileo
will be allowed to plead guilty to lesser
charges and will receive a lenient sentence.
On 30 April Galileo confesses that he may have
made the Copernican case in the Dialogue too
strong and offers to refute it in his next
book.
June Urban VIII decides that Galileo will be
imprisoned for an indefinte period.
With a formal threat of torture, Galileo is
examined by the Inquisition. The next day
he is sentenced to prison at the pleasure of
the Inqusition and to religious penances. The
sentence is signed by only seven of the ten
cardinal-inquisitors.
In a formal ceremony at a the church of Santa
Maria Sopra Minerva, Galileo abjures his errors.
First Galileo is allowed to be under house
arrest at the residence of the Tuscan
ambassador, and then at the residence of the
archbishop of Siena in that Tuscan city.
July Galileo arrives in Siena. Here he begins
putting together his Discourse on Two New
Sciences.
Dec. He is allowed to return to his villa in
Arcetri, near Florence, where he is under
house arrest for the remainder of his life.
1634 Winter Suffers from a painful hernia. He
requests permission from Rome to consult
physicians in Florence. The request is
denied, and he is given to know that
further requests such as this will result in
imprisonment.
Apr. Galileo's daughter, Maria Celeste, who has
lived in a convent near Arcetri for many
years, dies.
Summer A treatise on machines, entitled Mechanics,
completed by Galileo in 1602, has been
translated into French and is published in
France by Marin Mersenne.
1635 A Latin translation of the Dialogue is
published in Strassburg by Matthias Bernegger.
1636 Publication of Letter to the Grand Duchess
Christina in both Italian and Latin.
May Louis Elsevier, a Dutch publisher, visits
Galileo in Arcetri and agrees to publish the
Discourse on Two New Sciences in Leiden.
Aug. Galileo sends a proposal to the States General
of the Netherlands for determining longitude
at sea using eclipses of the satellites of
Jupiter.
Nov. The States General appoint a committee to
examine Galileo's proposal.
1637 Apr. The States General award Galileo a gold chain
worth 500 florins in recognition of his
longitude effort. His proposal was deemed not
to be practical.
July Galileo writes to Elia Diodati that he has lost all
vision in his right eye.
Nov. Announces he has discovered a new
libration of the Moon, different from the
optical libration.
1638 Jan Has lost vision in his left eye and is
now totally blind. He petitions the
Inquisition to be freed. The petition is
denied. He is, however, allowed to transfer
to his house in Florence in order to be closer
to his physicians. In March he obtains
permission to attend church on religious
holidays, provided that he have no contact
with others.
July The Discourse on Two New Sciences comes off
the press in Leiden in the Netherlands.
Aug. When the gold chain from the Dutch States
General is presented to Galileo, he refuses
it. For this he is commended by Pope Urban
VIII.
During a serious illness, Galileo prepares his
last will and testament.
Sept. John Milton visits Galileo in Arcetri.
1641 Galileo conceives of the application of the
pendulum to clocks.
1642 Jan. Galileo dies in Arcetri on 8 January.
