7.  1593 : Thermometer  1597 : Compass  1609 : Telescope  1641 : Pendulum Clock

8. People need a way to tell the temperature outside or inside Galileo was taking medical school at university of Pisa. His 1 st invention was the thermometer He construct the thermometer, which used the expansion and contraction of gas inside aglass bulb to move water in an attached tube

9.  Invented and improve a Geometric and Military Compass  In 1597, he built a compass used for aiming cannonballs  It was also adapted for civilian use in land surveying

10.  Though Galileo didn’t (Dutch opticians did), he improved upon it  The 1 st telescope used a combination of two lenses within a tube, and it could magnify items by three times, but showed them upside down  But when Galileo constructed his own telescope in 1609, he added a third lens. His telescope magnified items by 8 times and showed them right side up  Galileo built several telescopes, including one that would magnify item by a factor of 30

11.  Another invention that Galileo worked on was a pendulum clock  Galileo discovered isochronism - that the time it takes for the pendulum to swing is not linked to the arc of the pendulum  He also created a design for a pendulum clock in 1641, but never completed one before death

12.  Galileo discovered four of Jupiter’s largest moon: lo, Europa, Calisto, and Ganymede  In september of 1610, Galileo observed that Venus, like the moon, exhibited a full set of phases  This helped prove that the universe was heliocentric and not geocentric  Galileo was the 1 st to discover that the Moon was rough and uneven

16.  Galileo observed the Milky Way and found it to be stars that were packed together densely  Galileo located many stars that were too far from Earth to be visible with naked eye alone  In 1612, Galileo observed Neptune without realizing it was a planet he considered it to be just another dim star  Galileo was the 1 st to observe the sunspots

18.  Galileo worked on the motion of bodies in sky  Galileo proved that time of descent was independent of the mass of the object  Galileo was one of the 1 st people to understand how sound frequency worked  In 1632, Galileo presented a theory which explained the tides, based on the motion of the Earth  In 1638, Galileo described an experimental method to measure the speed of light

20.  https://en.wikipedia.org/wiki/Galileo_Galilei https://en.wikipedia.org/wiki/Galileo_Galilei  https://www.nndb.com https://www.nndb.com  www.galilieo.rice.edu www.galilieo.rice.edu