Announcements Exam 1 is one week from today. Covers Chapters 1 – 5. Sample questions are posted. Exam will consist of 15 multiple choice questions and 3 essay questions. Don’t forget the 1 st Project presentations are three weeks from today. 1 st Quarter Observing Night Monday night. Set-up starts at 6:45pm. Meet here at that time

After Tycho’s death, Kepler is appointed Astronomer Royal Kepler explains his astronomy to Rudolph II

A legal battle between Tycho’s family and Rudolph II keeps the data in limbo Kepler basically steals the data until ownership is eventually sorted out. Kepler credits Tycho in the Rudolphine Tables

With the data in hand, Kepler begins his “war on Mars”

The calculations were extremely tedious

Kepler’s 2 nd Law was actually his first Although he didn’t have the details worked out, he knew that planets travel fastest when closest to the Sun and slowest when farthest away before he knew the shape of the orbit.

Eventually he comes up with his 1 st Law of Planetary motion He publishes his first two laws in 1609

His 3 rd Law took another 10 years to develop Harmony of the Worlds is first published in 1619

His last publication is the Rudolphine Tables in 1627

As seemed fitting for his troubled life, his grave was destroyed within a few years of his death This is the house he lived in briefly in Regensburg. He had returned to try and collect on an old debt when he took ill and died. He was buried in the cemetery of the local protestant church. Within five years the church is destroyed and his grave is erased.

Galileo Galilei 1564 – 1642

Born in Pisa, his family moved to Florence when he was 8

At 17 he begins study at the University of Pisa Originally he studies medicine but is unhappy with it so he changes to mathematics. In 1589 he is appointed chair of mathematics at the university

In 1592 he moves to the University of Padua to teach math, geometry and astronomy

While at Padua he performs numerous physics experiments

Early on he is not yet a committed Copernican but he isn’t happy with Ptolemy either Vs He considers Tycho’s model a bastardization of Ptolemy and not worth bothering with

In the summer of 1609 he hears about a new invention: the telescope Invented by Hans Lippershey of Zeeland in 1608, word quickly spread across Europe to Galileo

After making refinements to the design, Galileo turns his telescope to the heavens

His first major discovery concerned the planet Jupiter Over a week long period in January 1610 he makes observations that prove the existence of four moons orbiting Jupiter.

His observations of the moon showed it to have topography similar to Earth

He publishes his first observations in the Starry Messenger Published in March He calls the moons of Jupiter the Medicean stars after his patrons Simon Marius claimed to have observed the moons before Galileo but didn’t publish his findings until after Starry Messenger came out

His next significant observations are of the Sun By tracking sunspots across the face of the Sun he deduces the rotation of the Sun. While he does make observations and sketches, his studies of the Sun are not as detailed as other observers of the time.

Another observation that supports his new Copernican views was the phases of Venus

He observes the rings of Saturn but never understands what they are He first observes it in July By 1612 the rings were edge-on and became invisible only to reappear by 1616

In December 1614 Father Tommaso Caccini preaches against the Copernican view The sermon is directly aimed at Galileo and is meant to incite ferment against the Copernicans

In 1615 Galileo is called to Rome to defend his views before Cardinal Bellarmine

In 1616 the Church formally bans De Revolutionibus Cardinal Bellarmine explicitly warns Galileo not to hold or espouse the Copernican view.

Galileo publishes more observations in The Assayer in 1623 He also attacks other astronomers that still hold to the Ptolemaic view.

In 1623 Galileo’s friend, Cardinal Barberini, becomes Pope Urban VIII

Emboldened by discussions with Pope Urban VIII, Galileo defies the Inquisition and publishes Dialoguesin 1632 Emboldened by discussions with Pope Urban VIII, Galileo defies the Inquisition and publishes Dialogues in 1632

By late 1632, is banned and Galileo is put on trial By late 1632, Dialogues is banned and Galileo is put on trial

By June 1633 he is found guilty and sentenced to prison. After recanting his views, his sentence is commuted to house arrest

While under house arrest, he finally publishes the results of his physics experiments Discourses and Mathematical Demonstrations Relating to Two New Sciences lays the foundation for kinematics and dynamics

He dies while still under house arrest, on January 8, 1642

If you have time…