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Astronomy

Workshop

Prepared by: Miss Julia GermannFrom: ASTRO

By: Seeds

& Other Science Related Sources

CH 1-5

Solar System

Milky Way Galaxy

Planet Earth

The Sun is a star on the Orion Arm

SOLAR ADDRESS:

1.Earth

2.Solar System

3.Orion Arm

4.Milky Way Galaxy

5.The Local Group

6.The Local Super

Cluster

7.The Universe

…continued

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Rotation of the Sky at the North Pole Rotation of the Sky at the Equator

**Mid-latitude stars :Some stars are always up, sometimes

up, or up half the time. Others are always down, sometimes down, or

down half the time.

*Stars move in a counter- clockwise motion **Stars rise vertically in the East, set

vertically in the West

WestEast

8 Phases of the Moon

Seasonal Changes:

Solstice -sun is stationary

Equinox-Equal day and Night

Solar Eclipse ◦ (sun is being blocked)

Lunar Eclipse◦ (moon is being blocked)

Eclipsed objects are blocked

Moon passes between the sun and Earth Moon passes through Earth’s shadow

Appearance: The sun looks like a ring surrounding the moon!

Appearance:

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Tidal Bulges

Hipparchus:

◦ created the apparent magnitude scale by dividing stars into categories according to their brightness (1-6).

Apparent brightness: how bright a star looks from Earth

Absolute brightness: how bright a star would be if it were a

distance of 10 parsecs away.

CH 3:The Origin of Modern Astronomy

Geocentric Universe vs. Heliocentric Universe:Refer to: The Origin of Modern Astronomy (Pg. 32-39)

Retrograde motion:

*the apparent backward motion of a planet as seen from a vantage

point

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Geocentric Universe vs. Heliocentric Universe:Refer to: The Origin of Modern Astronomy (Pg. 32-39)

Ptolemy's model (140AD):

“Earth-centered" or "geocentric"Copernicus’ model (1542 AD):

"Sun-centered" or "heliocentric"

celestial objects — including the planets, Sun, Moon, and stars —orbit Earth.

explains retrograde motion through epicycles

planets orbit the Sun, and the Moon orbits Earth. Since the Sun is the center of the universe, it does not move, nor does the stars.

*explains retrograde motion byplanets passing each other.

Ptolemy’s Epicycles

A. PLANETS MOVE IN ELLIPSES

B. EQUAL AREA IN EQUAL TIME

C. ORBITAL PERIOD SQUARED EQUALS THE CUBE OF THE SEMIMAJOR AXIS; p= orbital period; a=semi-major axis of the orbit

Kepler’s Three Laws:

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(1)An object remains at rest, or moves in a straight line at

constant speed, unless acted on by an outside force.

(2) The acceleration of an object is directly proportional to

force, and inversely proportional to mass.

(3) For every action, there is an equal and opposite reaction

Newton’s Laws

Earth’s moon is uneven and rough

Moons of Jupiter orbit so they disappear from day to night

the phases of Venus are similar to the moon

CH 4: Astronomical Telescopes and Instruments

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Refracting Telescope

CH5 Sun Light and Sun Atoms:

•Sunspots(11 Year Cycle)

•Magnetic Field

•Nuclear Fusion

1) Gravity

– pulls down onto the earth

1) electromagnetic force

– pushes

3) nuclear strong

– atomic bomb

4) nuclear weak

– radio activity

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Stellar SpectraWhen light is broken up into wavelengths:

Eye

Eye

Eye

CH 1-5 Review

• CH1: Scale of the Cosmos

• Solar Address:

Earth, Solar System, Orion Arm, Milky

Way Galaxy, Local Group, Local

Supercluster, Universe

• CH2: User’s Guide to the Sky

• Celestial Sphere

• 8 Phases of the Moon

• Eclipses

• Tidal Bulges

• CH3: The Origin of Modern Astronomy

• Hipparchus’s Magnitude Scale;

Ptolemy’s Geocentric Universe;

Copernicus’s Heliocentric Universe

• Laws/Observations: Kepler, Newton,

Galileo

•CH4: Astronomical Telescopes and

Instruments

•Telescopes:

•Refracting

•Chromatic aberration

•Reflecting

•Newtonian

•CH5: Sun Light and Sun Atoms

•The Sun: • 11 year sun cycle• magnetic field• nuclear fusion

•4 Fundamental Forces•Gravity•Electromagnetic•Nuclear Weak•Nuclear Strong

•Light Spectra•Visual, Emission, and Absorption