Astronomy

Anticipatory Set:

Describe the universe?

Universe

Resource:

www.universetoday.com

Big Bang Theory

Resource:

Astrophysics: Most distant cosmic blast seen

Bing Zhang

Nature 461, 1221-1223(29 October 2009)

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Big Bang Evidence

Evidence

• CBR - Horn Antenna Video
• Temperature in space
• RS (Video/Tuning Fork/Glasses)
• Doppler Effect

Resource:

www.pion.cz

• ​

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Vocabulary:

• Big Bang Theory
• Cosmic Background Radiation
• Electromagnetic Spectrum - Red Shift
• Doppler Effect
• Expansion

Construct a model (picture with words).

Celestial Objects

• Hubble Deep Field (Video + image)
• Compare Celestial object size/age
• What are Galaxies?

13

Structure of the Universe

Universe

Resource:

www.universetoday.com

CO’s - Solar Systems

• Define Solar System
• List non-star objects

Celestial Objects - Stars

• Star size
• What two factors affect gravity
• Describe fusion
• Explain why fusion happens in a star�

HR-Diagram

1. Read about the different types of stars. Be prepared to share at least 3 things you learned about each type. Page 41- 44. Answer Questions 7-15.
2. Interpreting the H-R Diagram on Page 15 ESRT.

Stellar Cycle

• What determines star type

21

Objective:

List and describe the life cycle of a star. YOLO!

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Specifically, how does nuclear fusion impact the life of a star?

Resource:

www.abovetopsecret.com

Resource:

faculty.wcas.northwestern.edu

black dwarf

Stellar Life Cycle

• Formation

We can’t directly observe a black hole but we can see its effect on the stars around it.

Nebula

Black Dwarf

supernova

HR-Diagram

1. Which is brighter Alpha Centauri or Barnard’s Star? (How do you know?)
2. Which is hotter Rigel or Betelgeuse? �(How do you know?)
3. Which is larger Deneb or Procyon B �(How do you know?)�

Non-Star Objects

• Asteroid Belt Story
• Pluto Story
• Uranus Story
• Foldable (Red book p48)
• Middle - Planet Characteristics
• Left - Terrestrial Characteristics (names)
• Right Jovian Characteristics (names)

71

Solar System Data Page 15

72

Planetary Motion - Rotation

• Football / Airplane Story
• Define Rotation (p. 49) (p. 15 ESRT)
• Give two pieces of evidence that the earth rotates

73

Planetary Motion - Revolution

• Constellation Demo
• Provide two pieces of evidence that Earth revolves around the sun.
• Compare / contrast revolution / rotation

74

Solar System Models

• Watch this animation. Make observations.
• Planet etymology - Latin
• Kepler’s Laws Animation
• Define geocentric and heliocentric
• Why did geocentric models not work?
• What is the correct shape of the planet orbits?
• What is the relationship between distance from the sun and orbital velocity?
• What is the relationship between distance from the sun and period of revolution?�

75

76

The Walking Dead Story

Read pages 69-70 red book answer questions 28-40

News Reporter Time Traveler Story

Local Solar Noon

Time zones are 15° wide (why?)

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As we go east to west, time decreases.

3am in California ? Time in NY?

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Time Zones

• West Wing
• Local Solar Noon
• Time zones are 15° wide (why?) 3am in California ? in NY?
• Read pages 69-70 red book answer questions 28-40

78

What time is it?

79

Calculating Eccentricity

• Orbital Velocity
• Calculating Ecc.
• Label the diagram
• Perihelion
• Aphelion
• Foci
• Major Axis

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80

Apparent Motion

• Time to spin!
• Polaris (Stellarium)
• How fast do stars move across the sky? --- Why?
• How fast does the Sun move?
• The Sun’s apparent motion

81

Calculating hours

• Based on the movement of the stars we can calculate how many hours have passed!
• Page 62-63
• Questions 1-6

82

The Seasons

Construct a model of the seasons showing the following

• The Sun
• Earth’s Orbit
• Include the direction earth is moving around the sun with an arrow.
• Earth at each of the four seasons
• (include the earth’s axis)

83

Seasons

• What causes the seasons?
• Concentrated vs Diffused
• Describe how the northern hemisphere is tilted in relation to the sun during OUR summer.
• What season will it be in the southern hemisphere at this time?
• When is Earth closest to the Sun?

84

85

86

Label in your notes

87

Label in your notes

N

S

W

E

88

89

90

Lunar Motions

Lunar

Phases - Stellarium

Eclipses

Solar

Tide Cycles

• Anticipatory Set
• Video of Bay of Fundy Tide
• Tides are caused by two�motions
• Moon’s revolution
• Earth’s rotation

92

Solar System Models

1. Watch this animation. Make observations
2. Define geocentric and heliocentric
3. Why did geocentric models not work?
4. What is the correct shape of the planet orbits?
5. What is the relationship between distance from the sun and orbital velocity?
6. What is the relationship between distance from the sun and period of revolution?�

93

Closure (4a)

• Check for understanding
• Discuss with your partner the following
• Put the following in order from youngest to oldest
• Universe
• Solar System
• Galaxy
• Put the following in order from largest to smallest
• Universe
• Solar System
• Galaxy
• Planet
• Star
• Record your answers in your notes.

Stars (4d)

• Anticipatory Set
• Size Video
• Gravity depends on mass/distance
• Fusion is the combination of two light elements into a heavy element
• H+H = He + Energy (light)
• Happens in stars because of massive gravity
• (causes high temp/pressure)

Closure (4d)

• Check for understanding
• Discuss with your partner the following
• What two factors affect gravity
• Describe fusion
• Explain why fusion happens in a star
• Record your answers in your notes

Stars Continued

• Size
• Fusion - YOLO?
• HR Diagram

Planets - Characteristics

• The eight planets are the largest objects that independently orbit the sun
• Planets do not share their environment with other larger objects/must have cleared its’ path of larger objects
• must orbit a star
• Most are spherical shapes due to own gravity
• 350 planets are known to revolve around stars other than our sun

Terrestrial Planets

• close to sun and mostly solid (high densities)
• Few or no moons, and no rings
• Planets similar to earth:
• Mercury, Venus, Earth, Mars

Jovian Planets

• Far from the sun and largely gaseous (low densities
• No solid surfaces = no craters
• Many moons and rings
• Planets similar to Jupiter:
• Jupiter, Saturn, Uranus, Neptune
• Pluto???

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Terrestrial or Jovian

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Which are more dense?

Terrestrial

Which have more moons?

Jovian

Which have longer periods of revolution?

Jovian

Which are larger in size on average?

Jovian

Motion of the planets - Rotation

• Planet rotation – planets spin on an imaginary axis

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• Period of rotation – amount of time it takes for a planet to make one spin around its imaginary axis and determines the length of a planet’s day

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• See ESRT, page 15

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Motion of the planets - Revolution

• Planet revolution – a planet’s movement around the sun in a path called an orbit
• Amount of time it takes for a planet to orbit the sun completely = 1 revolution
• Moves counterclockwise around the sun as viewed from Polaris
• Earth’s orbit (and the other planets) is an oval shape called an ellipse.
• Within the ellipse are two fixed points, called foci points.

Asteroids

• A solid rocky and/or metallic body that independently orbits the sun.
• Most are irregular shapes
• 1000’s of known asteroids between Mars and Jupiter

Resource:

asteroidapophis.com

Moons

• Body that orbits a planet or an asteroid as those objects orbit the sun
• 175 moons known

Resource:

atropos.as.arizona.edu

Comets

• Comet – an icy CB that heats up and flares when it gets close to the sun
• Sometimes has a tail

Resource:

bf-astro.com

Comet + Heat =

Resource:

www.today.com

STOP!

Let’s see what you learned today.

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We will be making a foldable pamphlet on planets. I will help you set it up, but you must finish for HW.

Evidence of Earth’s Rotation

• Foucault Pendulum
• When a pendulum swings freely, its path will appear to change in a predictable way
• Evidence of earth’s rotation
• Pendulum – due to inertia – would continue to swing in its original path if Earth did not rotate

Resource:

commons.wikimedia.org

Foucault Pendulum

• Path of foucault only appears to change
• Actually, pendulum swings in a fixed direction
• Earth rotates underneath the pendulum

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The Coriolis Effect

• Tendency of all particles of matter moving at earth’s surface to be deflected, or curve away, from a straight-line path.
• Northern Hemisphere – deflection is to the right
• Southern Hemisphere – deflection is to the left
• Deflection occurs because earth is rotating
• http://www.youtube.com/watch?v=rdGtcZSFRLk
• http://www.youtube.com/watch?v=_36MiCUS1ro

Evidence of Earth’s Revolution Around the Sun

• Earth revolves around the sun, in a slightly eccentric orbit, once a year

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• The earth revolves counter-clockwise 1 degree per day (360° in 365 days

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Seasons

• We know that Earth’s limited change in distance from the sun during the year does not causes seasons

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• Therefore, seasonal changes must be impacted by revolution

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• Seasonal Change

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If no revolution???

• The same part of Earth would tilt toward the sun all the time
• No changes in amount of sunlight during the year
• Seasons would not change

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Evidence of revolution from constellations

• Different constellations each season

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• Constellation – a group of stars that form a pattern; used to locate celestial objects

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• Constellations are visible when the dark side of earth faces toward the constellation

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Other evidence of earth’s revolution

• Apparent change in diameter of sun over a year
• Sun appears largest around January 3 (closest to earth)
• Sun appears smallest around July 4 (farthest from earth)
• Slight changes in doppler effect between stars as distance slightly changes

STOP!

Let’s see what you learned today.

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Start HW:

Page 68, # 20-27

Watch video on Eccentricity and complete WS on website

Eccentricity

• Eccentricity – the degree of “flatness” or ovalness of an ellipse

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As foci move closer together, the ellipse becomes more circular, and eccentricity moves closer to zero

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Inertia

• Inertia An object at rest will tend to remain at rest , and that an object in motion will maintain the direction and speed of that motion unless an outside force acts upon it

Gravitational Force

• Gravitational Force – attractive force that exists between any two objects in the universe
• The greater the mass of one or both objects (star and planet), the more gravitational attraction
• The closer the objects, the greater the gravitational force

2 models of the Solar System

Assumed Earth is stationary, and most CB’s revolve around it

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Geocentric Model

“earth-centered”

could not explain retrograde motion

Ptolemy

Aristotle

Heliocentric Model

“sun-centered”

Copernicus

The moon revolves around earth, as earth revolves around the sun

Earth both rotates (across an imaginary axis) and revolves around the sun in an orbit

Heliocentric

Retrograde motion View from Earth

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Retrograde motion (model)

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Actual Earth Motions - Thank you Heliocentric!

• Rotation – spinning of the earth on its axis
• imaginary line through the North and South Pole

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• Tilt – axis of earth is tilted 23.5°
• Earth rotates from west to east in 24 hours
• counterclockwise
• Rate of 15° per hour

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STOP!

Let’s see what you learned today.

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Start HW:

1. Page 65, # 15-19
2. Castle Learning 4 due Sun, November 2nd

Objective 5 - Apparent motion

Stars - Stellarium

Sun

Sun2

Local Time

Based on the position of the sun in the sky.

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Solar noon is when the sun is at the highest point.

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Tilt of the Earth

Explain what causes the seasons using the terms concentrated/diffuse rays

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Earth’s Tilt

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Graph paper

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Apparent Motion

• Apparent motion – a motion an object appears to make
• Can be real or illusions
• Ex: person spinning (real) versus seeing a room spin (illusion)
• Stars appear to move from east to west
• However, this apparent motion is caused by earth’s rotation

Apparent motion - Stars

Are star patterns “fixed” in the sky?

Why or why not?

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Star patterns appear fixed, because…

Stars are very, very far away from Earth?

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So what do we observe each night?

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• Stars move across the sky during the night…

−Some move faster

−Some move very little

−One doesn’t seem to move at all!

• The positions of stars with respect to each other seem to be fixed…

Star patterns appear similar every 24 hours…

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Why are star patterns in the winter different than those in the summer?

Summer Sky

Your location

EARTH

Horizon

Summer Sky

Your location 24 hours later

EARTH

Horizon

Winter Sky

Your location

EARTH

Horizon

Due to Earth’s revolution around the Sun, we look at different parts of the sky during different seasons…

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Why are star patterns different in NY than in the Australia?

The portion of sky we see depends on where we are located on Earth - Northern Hemisphere

Your location

Day sIde

Night side

You would not see these stars because they are under your horizon

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EARTH

Your horizon

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Your location

Day sIde

Night side

EARTH

Your horizon

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If you live down under

• Apparent Paths of objects are parallel to the Celestial Equator.
• Orientation depends on your latitude:
• At Equator: perpendicular to the horizon
• At Poles: parallel to the horizon
• Mid-Latitudes: Tilted by (90º–Latitude)

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Actual Motion

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• Star patterns repeat about every 24 hours…

• meaning star patterns do not change much from night to night.
• However, star patterns in the winter are different from that in the summer.

•Positions of stars (with respect to the horizon and the zenith) in the sky are different at different locations (latitudes) on Earth.

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Arcs

• The paths of all celestial objects moving in the sky are circular, or parts of a circle called an arc
• All motion occurs at a constant rate
• 15° per hour or 360 ° in 24 hours
• Movement of a celestial object over 24 hours is called daily motion

Apparent Motion of Planets

• From Earth, planets exhibit daily motion similar to stars
• Over weeks to months – planets appear to change position with the stars around them
• Each year – a similar planet and star motion is observed, but in a different region of the sky
• Using the sun as a reference point, the complicated motions of planets is a result of different orbits at different speeds

Apparent Motion of Planets

Retrograde motion

�Retrograde motion (with path)

�Retrograde motion (model)

Apparent Motion of Earth’s Moon

• Our moon also follows daily east-to-west motion of stars
• However, it appears to rise about 50 minutes later each day and shifts eastward each day compared to the background field of stars

Resource:

www.theskinspecialist.com

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Apparent Motion of the Sun

• The sun also seems to move in the sky
• The sun’s apparent path, from sunrise to sunset has the shape of an arc
• Sun’s path changes its position and length with the seasons
• The greater the length of the path – the more hours of daylight it has

Resource:

www.theskinspecialist.com

Apparent Motion of the Sun

• Sun will apparently rise and set in different locations for each season

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• Summer daylight is longest

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• Spring & Fall in between approx. 12 hrs

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• Winter daylight is shortest

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Changes in the Altitude of the Sun At Noon

• Daily altitude of the sun is lowest at sunrise and sunset
• Daily altitude of the sun is highest at noon
• Solar noon = when the sun is at its’ highest point
• However, the altitude of the sun at noon depends on time of year, and latitude of observer

Changes in the Altitude of the Sun At Noon

• Only between latitudes 23.5° N and 23.5° S can the noon sun be directly overhead at an altitude of 90°

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• What are these points called?

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Tropic of Cancer and Tropic of Capricorn

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Earth and Moon Motions and Time

• Earliest civilizations have used actual motions of earth, and/or the moon to determine time
• Length of one cycle of our moon’s phases is one month
• Length of one rotation of Earth by apparent motions of the sun is one day
• One revolution around the sun, measured by apparent changes from sun and stars is one year

Local Time

• Local time – time based on rotation of Earth
• All places on the same meridian have the same local time
• Locations slightly away from a meridian (east or west) have different times
• Local time changes because of Earth’s rotation
• Two types of time based on observations of the sun at a single location

Local Solar Time

• For any location, the sun reaches its highest point at solar noon
• Solar day – time it takes for Earth to rotate from solar noon to solar noon on 2 successive days
• Calculated by use of a sundial, measures apparent solar time

Solar Time

• Earth’s speed around the sun varies in the course of a year
• As a result, length of apparent solar day varies
• Days with varying length make it hard to measure time using clocks and watches
• Therefore, we use mean solar day (average length)
• Mean solar time is around 24 hours

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Time Zone or Standard Time

• Used to standardize time for regions
• To minimize calculating mean solar times for place on Earth, we use time zones
• Time zones – 24 zones, 15 degree-wide bands
• Each band has a 1 hour time difference

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STOP!

Let’s see what you learned today.

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Start HW:

• Page 70, # 28-40
• Castle Learning 4 due Sun, November 2nd

Objective 6 - Lunar Motions

Lunar

Phases - Stellarium

Eclipses

Solar

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Hawaii

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One-half of the Moon is always illuminated by the Sun’s light, but the entire lighted half is visible from Earth only at full moon. The rest of the time you see portions of the lighted half. These portions are called lunar phases.

According to the ESRT, Earth’s moon has a revolution period of 27.3 days. However, to complete one lunar phase cycle it takes 29.5 days.

WHY MR. SCIENCE MAN?

Moon's Orbit

Tide Cycles

Causes of Tides

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