Earths Role as a Body in Space Lesson

Earth’s Role as a Body in Space

Lesson 1 Earth’s Position and Movement Through Space (You Are Here )

Earth’s Position in Space What is Earth’s position within the hierarchy of the universe?

A. Earth’s Position in the Universe… Earth l Solar System (3 rd planet from Sun) l Milky Way Galaxy (the Orion Arm) l Local Group (about 40 galaxies) l Supercluster (Virgo) https: //www. youtube. com/watch? v=_IVq. M l Universe! l XPFYw. I Pure Education Detailed Observation of the Universe http: //www. atlasoftheuniverse. com/

Earth’s Motion through Space How is Earth’s motion related to the origin of the galaxy and its solar system?

The Origin of Our Expanding Universe 1. The Big Bang Theory – universe began as a point & has been expanding ever since Notice how the galaxies in each successive picture are moving apart from the singularity? en. wikipedia. org

The Origin of the Milky Way 2. Astronomers hypothesize that the galaxy began as… A rotating, spherical cloud in space … a. Our solar system continues to orbit the center of the Milky Way because… it developed in the plane of the disk that orbited the central nuclear bulge of stars http: //www. google. com/imgres? imgurl=http: //casswww. ucsd. edu/archive/public/tutorial/images/mw. jpg&imgrefurl=http: //casswww. ucsd. edu/archive/public/tutorial/MW. html&usg=__

b. A Diagram – Milky Way Galaxy Formation l l http: //lcogt. net/education/article/milky-way-galaxy http: //astronomy. nju. edu. cn/~lixd/GA/AT 423/HTML/AT 42304. htm

The Origin of the Solar System 3. Our solar system began when… …a rotating, interstellar cloud of gases (nebula) collapsed (due to gravity) & formed a sun & orbiting planets a. Earth orbits the Sun because … it was located outside the center of the spinning nebula

A Diagram - Origin of the Solar System (Draw this!) • http: //csep 10. phys. utk. edu/astr 161/lect/solarsys/nebular. html Early stages of rotating cloud of gas & dust Rotating cloud flattens as it contracts Sun forms in center & planets form within flattened cloud. Radiation from the Sun drives away the “atmosphere” of hydrogen gas from the inner planets.

Lesson 2 Kepler’s Laws and Earth’s Orbit

Kepler’s Laws (Introduction)… Johannes Kepler, working with data painstakingly collected by Tycho Brahe (from 1576 -1601) without the aid of a telescope, developed three laws which described the motion of the planets across the sky. http: //www. nmspacemuseum. org/halloffame/images. php? image_id=131 Unless otherwise noted, the info on the slides on Kepler’s laws was taken from the following website: http: //hyperphysics. phy-astr. gsu. edu/hbase/kepler. html

1. Kepler’s First Law… The Law of Orbits: All planets move in elliptical orbits, with the sun at 1 focus. a. An ellipse is … oval shape centered on 2 points instead of 1 point. b. The orbital period of a planet is … how long it takes for it to travel a complete orbit around the Sun. c. We call this a year!

2. Kepler’s Second Law… The Law of Areas: A line that connects a planet to the Sun sweeps out equal (=) areas in equal (=) times. a. Earth sweeps out a longer path when it is closer to the Sun. b. Earth moves fastest when it is closest to the Sun. http: //phet. colorado. edu/en/s imulation/my-solar-system http: //www. mathacademy. com/pr/prime/articles/kepler/index. asp

3. Kepler’s Third Law… The Law of Periods: The square of the orbital period of any planet is proportional to the cube of the semi major axis of its orbit. a. P² = a³ (P = orbital period = unit of time in Earth yrs, a = length of the semi major axis) b. If you know the distance of a planet to the Sun, you would be able to figure out its… orbital period. c. Basically… The closer a planet is to the Sun, the shorter its orbital period is.

Kepler’s Third Law Another way of thinking about this is that …The closer a planet’s orbit is to the Sun, the shorter its year will be. (Write that in the margin!) l For Examples: Appendix J on p. 921… l l l Mercury’s year is 88 (Earth) days Venus’ year is 224 (Earth) days Earth’s year is 365 (Earth) days Mars’ year is 686 (Earth) days Neptune’s year is 60, 189 (Earth) days!!

Practice! Orbit Eccentricity l l The eccentricity of an ellipse can be defined as the ratio of the distance between the foci to the major axis of the ellipse. The more eccentric an orbit, the more of an oval it is. The eccentricity is zero for a circle. Of the planetary orbits, only Pluto has a large eccentricity. http: //solarsystem. nasa. gov/multimedia/display. cfm? IM_ID=175

Mini-Lesson 2: Barycenter The True Center of the Solar System!

Mini Lesson 2: Barycenter and Earth’s Orbit… Barycenter is …the center of mass between a planet and the Sun. 1. The law of universal gravitation states that… l every pair of bodies in the universe attracts each other with a force related to… l …mass (the more mass they have, the stronger the pull) AND l …distance (the farther apart they are, the weaker the pull)

Barycenter, Universal Gravitation, and the Wobbling Sun l The Sun wobbles around in its orbit because… l … the 8 planets are pulling on it as they orbit it!

Barycenter and Earth’s Orbit… 2. A planet, such as Earth, actually orbits… its barycenter with the Sun 3. The Sun orbits … the barycenter of the solar system. (It is NOT stationary in the sky as planets orbit it. ) 4. Draw this! See next slide. http: //www. barewalls. com/pv-605547_Barycenter-Diagram. html

Lesson 3 Earth’s Rotation Day and Night Earth’s Slightly Squashed Shape

Earth’s Rotation Causes Day and Night 1. Earth’s axis is… o … the imaginary line that goes through the N & S poles. 2. Day and night are caused by… l … the rotation of Earth on its axis spinning towards & away from the Sun. (23. 9345 hrs)

3. When the Sun “rises” … § … we are actually spinning TOWARDS it § Sun “rise” on Myrtle Beach (looking towards the east over the Atlantic Ocean)

4. When the Sun “sets” … § … we are actually spinning AWAY FROM it § … sun “set” over Ft. Lauderdale, FL (looking towards the west while on the Atlantic Ocean)

Think About It… Why are there 24 hours in a day? Earth spins… 15 degrees each hour There are 360 degrees in a circle (the circumference of Earth). 360 divided by 15 is 24 so there are 24 hours in a day! http: //huntingtonastro. wikispaces. com/file/view/earth-rotation. png/199559520/earth-rotation. png

Still Thinking About It… The exact amount of time it takes Earth to spin one time on its axis is… l 23. 9345 hours l If an Earth day was 5832. 5 hours long (like that of Venus!) then… l It would take 243 days for Earth to spin one time on its axis! l Our day and night would be much longer! (And it would get really hot and really cold!)

Earth’s Rotation Causes Its Slightly -squished Shape… 1. What motion causes Earth to take the shape of an oblate spheroid? Earth’s rotation 2. What force causes the Earth’s mass to move outward from its center at the equator as Earth rotates? centrifugal force

Earth’s Rotation Causes Its Slightly -squished Shape… 3. There is a slight bulging at the equator and a slight squishing at the poles. 4. This causes the circumference at the equator to be slightly larger than that of the poles.

Earth’s Rotation and Its Shape… 5. Draw this Notice the equatorial diameter is 42 km more than the polar diameter! Simulation: http: //www. cleonis. nl/physics/phys 256/equatorial_bulge. php

Lesson 4 The Seasons

Earth’s Orbit and Seasons… 1. The ecliptic is… l …the plane on which Earth orbits around the Sun http: //en. wikipedia. org/wiki/Ecliptic

Earth’s Orbit and Seasons… 2. The tilt of Earth’s axis relative to the ecliptic is 23. 5 degrees. http: //republicanredefined. com/2010/03/02/chile-quake-shifted-earths-axis-and-made-days-shorter/

http: //www. exploratorium. edu/ancientobs/chaco/HTML/TG-shadows. html 3. Draw The Seasons!

Earth’s Orbit and the Seasons! 4 a. What causes summer in the northern and southern hemispheres? when the hemisphere is tilted toward the Sun during Earth’s orbit

Earth’s Orbit and the Seasons! Fall occurs when a hemisphere is starting to tilt away from the Sun.

Earth’s Orbit and Seasons… 5. The seasons in the northern and southern hemispheres are opposite each other because… l When 1 hemisphere is tilted towards the Sun, the other is tilted away from it

http: //www. onlytoptens. com/wp-content/uploads/2011/08/top-10 -documentaries-march-of-the-penguins. jpg Seasons - Perihelion 6. Earth is closest to the Sun in January a. Our winter! b. This is called perihelion http: //solarsystem. nasa. gov/scitech/display. cfm? ST_ID=2517

Seasons - Aphelion 7. And farthest from the Sun in July a. our summer! b. This is called aphelion But in Antarctic it is winter (which makes it tough on

Lesson 5 Changes in The Seasons – Precession and Nutation

Precession is… l the wobble in Earth’s rotational axis. 1. One full cycle of precession takes… l 26, 000 years! 2. The force that causes precession is… l the sideways pull of the Moon & Sun on the Earth’s bulging equator. https: //www. youtube. com/watch? v=d. Fzhjnj Xc 2 o (Weebles wobble…)

The Moon’s orbit is tilted 5° which over time pulls on Earth… http: //earthsky. org/astronomy-essentials/what-is-the-ecliptic

Precession… 3. Our current north star is… l Polaris l In about 12, 000 years, our new north star will be… l. Vega http: //www. wwu. edu/skywise/a 101_precession. html

Precession and Our Seasons… 4. Draw this! Aphelion Perihelion Winter Summer July In 14, 000 yrs January Aphelion Perihelion Summer Winter July Present January http: //earth. usc. edu/classes/geol 150/stott/variability/orbitalchanges. html

A New North Star and Our Seasons… 5 a. Winters in the N. hemisphere will be… in June, July, and August l It will be colder here because Earth will be farthest from the Sun. l 5 b. Summers in the N. hemisphere will be… in December, January, and February l It will be warmer here because Earth will be closest to the Sun. l

http: //www. cgrer. uiowa. edu/people/carmichael/atmos_course/ATMOS_PROJ_99/bilskemp/natural_variability. html Nutation… Nutation is… … a change in the angle of tilt of Earth’s axis 1. Present tilt of Earth’s axis is 23. 5°. 2. The tilt can vary from 22. 1° to 24. 5 °.

http: //www. cgrer. uiowa. edu/people/carmichael/atmos_course/ATMOS_PROJ_99/bilskemp/natural_variability. html Nutation… 3 a. If the angle of tilt decreased to 22. 1… there would be less of a temperature difference b/tw seasons. 3 b. If the angle of the tilt of Earth’s axis increased to 24. 5… there would be more of a temperature difference b/tw seasons.

Lesson 6 Tides

Tides… Tides are caused by… l the gravitational attraction among Earth, the Moon, and the Sun. 1. Tides are… the periodic rise and fall of sea level. a. High tide… lhighest level to which the water rises b. Low tide… llowest level of the water

2. What forces & heavenly bodies cause the tides? l l l gravitational pull of Moon on oceans facing it causes high tide “centrifugal swish” oceans facing away from Moon experience less of a pull (high tide) The sides of Earth NOT directly facing toward or away from the Moon experience low tide. The Cause of Tides…

The Cause of Tides… 3. What motion causes tides at location to change every 6 hours? l Earth’s rotation on it’s axis 4. The times of tides vary each day because the moon orbits the Earth every 28 days Tide Simulation: http: //astro. unl. edu/classaction/animations /lunarcycles/tidesim. html

http: //loneswimmer. com/2010/08/23/tides-for-swimmers-part-1 -theory/#jp-carousel-535 Spring Tide… Twice a month, the Earth, Moon, & Sun align (line up) causes the Moon & Sun to pull together on Earth’s oceans. l Higher high tides / lower low tides l

Twice a month, the Earth, Moon, & Sun will form a right angle which causes the Moon & Sun to pull from different directions on Earth’s oceans. l Evens the tides l Neap Tide… http: //www. yourdictionary. com/neap-tide

http: //mail. colonial. net/~hkaiter/Moon_Phases_Tides. html 5. Draw the Tides… (as seen from above the North Pole!)

Lesson 7 Energy Reactions

A Little Bit About the Sun… How many Earths could be lined up edge to fit across the Sun? l l 109 (and 1 million Earths would fit IN it!) Pic on next slide… The Sun makes up… l 99% of the mass of the solar system! A pair of dice with the density of the Sun… l would weigh 2 pounds! The solar interior is made of… … plasma (one of the 4 states of matter)

Fusion 1. Fusion is… – the fusing of smaller, lighter hydrogen atoms to form a larger, heavier helium atom (which releases energy)

Fusion… Fusion occurs in the stars! (our Sun) Or in Iron Man’s chest… Click on link… a. http: //www. outerplaces. com/science/item/7048 -how-iron-mans-stark-arc-reactorwould-work-in-real-life http: //scifi. stackexchange. com/questions/43005/did-starkalready-have-a-design-of-an-arc-reactor-in-mind

Fusion… Or in Doctor Octopus’ Lair… Click on link… http: //www. comicbookmovie. com/fansites/ Ultimate. Marvel. Movie. Fan/news/? a=102351

Fusion… bi. During fusion, the two atoms that fuse to form a helium atom are the H isotopes deuterium & tritium

Fusion… b. During Fusion (continued)… ii. The mass that is lost when two hydrogen nuclei fuse to form helium … l… gets converted into energy iii. The theory of special relativity (e = mc²) by Albert Einstein relates mass to energy! http: //www. nobelprize. org/nobel_prizes/physics/laureates/1921/einstein-bio. html

Fission 2. Fission is… – splitting of bigger, heavy atoms (like uranium or plutonium) into smaller, lighter atoms

2 a. Fission Differs From Fusion… a. Fission differs from fusion in that… Fission is SPLITTING atoms, not FUSING atoms. The Radioactive Boy Scout is a warning about investigating fission in your backyard shed! http: //www. dangerouslaboratories. org/radscout. html

2 b. Fission is used on Earth … – in nuclear power plants & submarines (to generate electricity) www. pollutionissues. com

Fusion and Fission: Nuclear Reactions 2 c. Fusion and fission are nuclear reactions because… Ø …the nuclei of atoms are fusing (in fusion) OR splitting (in fission). (Remember… That’s the center part of the atom where protons and neutrons are located) Ø New atoms are made in both types of reactions.

Combustion http: //en. wikipedia. org/wiki/Combustion 3. Combustion is… burning of a fuel in presence of O 2 (oxygen) to produce energy (heat & light) a. It is a chemical reaction which recombines atoms. (FUEL) Methane

Power Plants… 3 c. In the approximately 1, 600 power plants in our country that use combustion, the fuels used are mostly… ü coal & natural gas ü Belews Creek is coal-fired.

Combustion – Draw it! Fuel + oxygen carbon dioxide + water

Lesson 8 The Sun’s Energy

The Sun’s Energy… 1. Electromagnetic radiation consists of … l … electric & magnetic disturbances that travel through space as waves. 2. The electromagnetic spectrum… l …organizes forms of EM energy by wavelength 3. The Sun produces electromagnetic radiation across the spectrum… l radio waves, microwaves, infrared energy (heat), visible light, ultraviolet radiation, xrays, & gamma rays

The Electromagnetic Spectrum… 4. The shorter the wavelength, the more harmful the energy! http: //www. lbl. gov/Micro. Worlds/ALSTool/EMSpec 2. html

The Ozone Layer… 5. Which gas blocks ultraviolet radiation from the Sun? l Ozone (O 3) a. It is found in the stratosphere. b. Chlorofluorocarbo ns (CFCs) damage O 3. c. These are found in aerosols, coolants, & http: //mmedia. pl/ozone-layer-diagram-for-kids

Solar Wind and Earth’s Magnetic Field 1. Solar wind is… l …a supersonic plasma (Remember, that’s charged particles or ions) that flows outward from Sun at high speeds &… l …bathes planets in a flood of highenergy particles. (Which isn’t very good for us!)

Solar Wind and Earth’s Magnetic Field… 2. Earth’s magnetic field protects us from the solar wind by… l deflecting these particles and trapping them in two huge rings (Van Allen belts) http: //www. redorbit. com/education/reference_library/space_1/solar_system/2574610/van_allen_radiation_belt/

The Strength of Earth’s Magnetic Field… Our magnetic field is decreasing by 5% a century l Jupiter has a super-strong magnetic field l What would happen if our magnetic field was much stronger? Take a look… l https: //www. youtube. com/watch? v=et. PXBm 0 z. Rv. M

Solar Wind and Earth’s Magnetic Field… 4. The auroras are created when… l … high-energy particles in Van Allen belts collide with gases in Earth’s atmosphere & give off light l See next slide…

Lesson 9 Energy For Earth…

Energy For Earth… 1. Radiation is … transfer of energy through space by EM waves (visible light, ultraviolet radiation, & other) http: //virtualskies. arc. nasa. gov/weather/images/2 b 1. png

Energy For Earth… 1 a. The Sun’s energy reaches Earth by the process of radiation. 1 b. About 50 % of the Sun’s energy is absorbed by Earth’s surface. 1 c. Remember – ozone blocks most of the UV radiation. http: //ossfoundation. us/projects/environment/global-warming/earths-radiation-budget

Differential Heating… 1 d. Which heats up and cools down more slowly – water or land? l This is called differential heating. l This is what moderates the climate in coastal areas. l In winter, the ocean acts like a giant heater and in summer, the ocean acts like a giant air conditioner.

2. Conduction is… the transfer of energy that occurs when molecules collide a. Air molecules just above Earth’s surface are warmed by conduction. b. Energy moves from your hand to your desk. Why? Energy for Earth… Heat waves over hot sand! http: //visualparadox. com/wallpapers/dryseason 1600. htm

Energy for Earth… 3. Convection is… l a. b. c. the transfer of energy by the flow of a heated substance Warm air will rise. When the warm air gets high enough, it cools and sinks. This creates a http: //avstop. com/ac/fig 5 -9. jpg

Energy for Photosynthesis… 1. 2. 3. 4. 5. During photosynthesis, solar energy is transformed into chemical energy (food). This occurs in plants, algae & some bacteria. For this to occur, there must be water, CO 2, Energy source: sunlight. In plants, this occurs in http: //abhsscience. wikispaces. com/Photosynthesis+TD

6. Draw Photosynthesis…