astro page 5

Galileo's Telescope Observations

1.Craters of the moon

2.Observed many more stars visible than seen by the naked eye

3.Observed the four moons of orbiting Jupiter (known as the Galilean moons)

4.Observed strange bulges at the sides of Saturn

5.Observed the phases of Venus

6.Found sun spots on the sun's surface which moved spots

Force of Gravity- Newton

-Strength of gravity force depends on two things:

1.Mass of the two objects

-Higher mass - stronger gravity force

- lower mass - weaker gravity force

2.Distance between the two objects (must be measured center to center)

-Closer distance- stronger gravity (less ground to cover)

-Farther distance -Weaker gravity force-The angle of the sun depends on your point of view.

-Solar eclipse- when the moon and sun align

History of Astronomy

-40                   -Claudius Ptolemy

-1473- 1543   -Nicholas Copernicus

-1546- 1601   - Tycho Brahe

-1573-  1630  -Johannes Kepler

-1564- 1642   - Galileo Galilei

-1642- 1727   -Issac Newton

History of Astronomy

-40 Claudius Ptolemy- Geocentric universe (Earth centered)

-1473- 1543- Nicholas Copernicus- Heliocentric Universe (sun-centered)

-1546- 1601- Tycho Brahe- First to make precise measurements of planet positions  helped Kepler with data to continue research and figure out the laws he found

-1571- 1630- Johannes Kepler- First to determine laws of planetory motion

-1564- 1642- Galileo Galilei- First telescope observation of the heavens

-1642-1727- Issac newton- First to determine/ describe what controls the motions of objects in the heavens (law of gravity)

-Celestial sphere- a Greek idea of the sky represented as a sphere surrounding earth on which the stars were carried.

-Geocentric- earth is center of the universe

-Heliocentric- sun is the center

-Perihelion- closest point in an orbit  around sun

-Aphelion- farthest point

     -Peri= close

     -aph= far

-Planets speed up + slow down in eclips= Kepler's second law

-Planets constantly change speed in different parts of their orbits

-fastest when closest to the sun

-slowest when farthest from the sun

Keplers laws of planetary motion

1.Orbits  are elliptical (not circular)

2.Planets constantly change speed in orbits

-fastest when closest to the sun

-slowest when farthest from the sun

Galileo's Telescope Observations

1.Craters of the moon

2.Observed many more stars visible than seen by the naked eye

3.Observed the four moons of orbiting Jupiter (known as the Galilean moons)

4.Observed strange bulges at the sides of Saturn

5.Observed the phases of Venus

6.Found sun spots on the sun's surface which moved spots

Force of Gravity- Newton

-Strength of gravity force depends on two things:

1.Mass of the two objects

-Higher mass - stronger gravity force

- lower mass - weaker gravity force

2.Distance between the two objects (must be measured center to center)

-Closer distance- stronger gravity (less ground to cover)

-Farther distance -Weaker gravity force