Astronomy Chapter 22-25

Warm Up: Sept 7 KGqIU – creepy twinkle KGqIU pAuU –cute twinkle pAuU Compare and contrast each version using a Venn Diagram Which one do you like more? Why? Which one best describes human curiosity towards outer space? WHY? 2

Time Line Create a time to include each of the following people (include their discovery). Create a time to include each of the following people (include their discovery). Aristotle Aristotle Eratosthenes Eratosthenes Hipparchus Hipparchus Aristarchus Aristarchus Claudius Ptolemy Claudius Ptolemy Nicolaus Copernicus Nicolaus Copernicus Tycho Brahe Tycho Brahe Johannes Kepler Johannes Kepler Galileo Galilei Galileo Galilei Sir Isaac Newton Sir Isaac Newton

What is the Golden Age of Astronomy? The shift away from the idea of a Geocentric Universe. The shift away from the idea of a Geocentric Universe.

What is Modern Astronomy? Nicolaus Copernicus ( ) Nicolaus Copernicus ( ) Earth is just a planet Earth is just a planet Universe is sun centered Universe is sun centered Mercury, Venus, Earth, Mars, Jupiter, and Saturn Mercury, Venus, Earth, Mars, Jupiter, and Saturn Circular orbits around sun Circular orbits around sun Tycho Brahe ( ) Tycho Brahe ( ) Used pointers to estimate distance Used pointers to estimate distance Pointers think big protractor Pointers think big protractor Mentor Kepler Mentor Kepler

Who was Johannes Kepler ( )? Brahe’s observations of Mars Brahe’s observations of Mars Noticed that the orbit was not Circular Noticed that the orbit was not Circular Kepler used his Q&A’s to form 3 Laws of Planetary Motion Kepler used his Q&A’s to form 3 Laws of Planetary Motion 1 st Law 1 st Law Ellipse (Oval) Ellipse (Oval) 2 foci 2 foci Star Star

Laws of Planetary Motion 2 nd Law 2 nd Law Sun sweeps over equal areas in the same amount of time. Sun sweeps over equal areas in the same amount of time. Close to sun faster Close to sun faster Away from sun slower Away from sun slower 3 rd Law 3 rd Law Orbital Period (time) of planet is proportional to distance from the sun (P 2 =d 3 ), expressed in AU units (1AU = 1.5Million Km) Orbital Period (time) of planet is proportional to distance from the sun (P 2 =d 3 ), expressed in AU units (1AU = 1.5Million Km)

Who is Galileo Galilei?( ) Telescope Telescope Behavior of moving objects Behavior of moving objects Observation supported Copernicus’s view of the universe Observation supported Copernicus’s view of the universe Moons of Jupiter (4) = Earth is not the center of all universal motion Moons of Jupiter (4) = Earth is not the center of all universal motion Planets are circular disc = must be Earth-like Planets are circular disc = must be Earth-like Venus has phases like the moon = orbits light source (sun) Venus has phases like the moon = orbits light source (sun) Moon’s surface not smooth = validated others who named areas based on features (Sea of Tranquility) Moon’s surface not smooth = validated others who named areas based on features (Sea of Tranquility) Sun has dark regions = tracked movement est. rotation period of sun under 1 month Sun has dark regions = tracked movement est. rotation period of sun under 1 month

What is the Law of Universal Gravitation? Sir Isaac Newton ( ) Sir Isaac Newton ( ) ⊗ Kepler “some force pushes the planets along their orbits”  Galileo “no force is required to keep an object in motion” Inertia Inertia Every body attracts directly proportional to mass & inversely proportion to distance 2 b/w the bodies Every body attracts directly proportional to mass & inversely proportion to distance 2 b/w the bodies Revised Kepler’s 3 rd law (mass) Revised Kepler’s 3 rd law (mass)

What are Earth Motions? Rotation Rotation Spinning on axis (day/night) Spinning on axis (day/night) Solar day Solar day noon to noon noon to noon Sidereal day Sidereal day Based on a distant star Based on a distant star 23hr 56 min 23hr 56 min Distance to the stars change by tiny increments Distance to the stars change by tiny increments Sun changes by 1° a day Sun changes by 1° a day

Earth Motions Cont. Revolution Revolution Moving around another body Moving around another body Distance of the sun to the million km Distance of the sun to the million km Elliptical Orbit Elliptical Orbit January 3 January million km 147 million km million km 152 million km

Earth Motions Cont. Precession Precession Change in tilt of axis Change in tilt of axis 23.5  always the same 23.5  always the same years years Changes North Star Changes North Star Polaris to Vega Polaris to Vega Nutation Nutation Wobbling around the axis Wobbling around the axis Caused but the moon’s pull Caused but the moon’s pull Slight seasonal change. Slight seasonal change. Remember: Galaxies on the move! Remember: Galaxies on the move!

What are Axis & Seasons? Why do different season exist?

Axis & Seasons cont.

Moon (Satellite) Motions Revolution = 1month (29 ½ days) Revolution = 1month (29 ½ days) Ave. distance = Km (6%) Ave. distance = Km (6%) Perigee = closest to Earth Perigee = closest to Earth Apogee = farthest Apogee = farthest Phases of the Moon Phases of the Moon Waxing Waxing Waning Waning

How do Eclipses work?

What is Barycenter? The center of mass is the balance point between two orbiting bodies, like a seesaw. The center of mass is the balance point between two orbiting bodies, like a seesaw.

The Sun Average Star Average Star Some Stats: Some Stats: Diameter = 109 Earth diameters Diameter = 109 Earth diameters Volume = 1.25 million times Earth’s Volume = 1.25 million times Earth’s Mass = 332,000 times Earth’s Mass = 332,000 times Earth’s Density = 1/4 th of solid Earth Density = 1/4 th of solid Earth

Sun Structure Structure Structure the Solar Interior the Solar Interior Photosphere Photosphere 2 Atmospheric Layers 2 Atmospheric Layers Chromosphere Chromosphere Prominences Prominences Corona Corona Solar Winds Solar Winds

Solar Flares & Sunspots Solar Flares Solar Flares Auroras Auroras Sunspots Sunspots 11 year cycle 11 year cycle Last days to weeks Last days to weeks

The Solar interior Nuclear Fusion Nuclear Fusion E=mc 2 E=mc 2 It takes very little hydrogen to make a lot of energy. It takes very little hydrogen to make a lot of energy. Most of the hydrogen is not converted to energy. Most of the hydrogen is not converted to energy.

Other Stuff Scientific Methods Quiz Redo Scientific Methods Quiz Redo A problem is a question to be answered!!!!! A problem is a question to be answered!!!!! Answer the QUESTION!!!!!!!!!!!!!!!! Answer the QUESTION!!!!!!!!!!!!!!!! Do not for get the problem/hypothesis relationship!!!!! Do not for get the problem/hypothesis relationship!!!!! Example Problem: Example Problem: Does the presence of grain-eaters in the desert environment cause a decrease in wildflower diversity? Does the presence of grain-eaters in the desert environment cause a decrease in wildflower diversity? Example Hypothesis: Example Hypothesis: If grain-eaters are eliminated from the environment by a fence, then the wildflower diversity will increase by 20%. If grain-eaters are eliminated from the environment by a fence, then the wildflower diversity will increase by 20%. Independent Variable Independent Variable Dependent Variable Dependent Variable Write so anyone knows what you are saying!!!!!!! Write so anyone knows what you are saying!!!!!!!

Other Stuff On the Scientific Method Quiz, if your grade is: On the Scientific Method Quiz, if your grade is: = Awesome Job!! = Awesome Job!! = Good, but needs some work = Good, but needs some work = OK, but what are you at a loss about? 7-10 = OK, but what are you at a loss about? 0-6 = Get help before the test Wednesday!!! 0-6 = Get help before the test Wednesday!!! On the Astronomy Quiz, if your grade is: On the Astronomy Quiz, if your grade is: = Stellar Performance!! = Stellar Performance!! 18 = Awesome Job!! 18 = Awesome Job!! = Good, but needs some work = Good, but needs some work = Ummmhhhh I think you need to study!!! 9-14 = Ummmhhhh I think you need to study!!! Below a 9= Seek help before Wednesday test!!! Below a 9= Seek help before Wednesday test!!!

The Golden Age Astronomers Aristotle ( BC) The Earth is round. Aristarchus ( BC) 1 st to believe in heliocentric universe