Looking South from Syene Egypt Latitude: 24º N Scorpius Looking South from Athens Greece Latitude: 38º N Scorpius

Earth Shadow during Lunar Eclipse Multiple Exposure Photograph

Alexandria Cyrene Tropic of Cancer Syene

Alexandria Earth 7 14 / 60 º Sunlight

North Pole South Pole Equator

South Pole Equator North Pole

Meridian North Pole South Pole Equator

South Pole Equator North Pole Meridian

South Celestial Pole North Celestial Pole Celestial Sphere Celestial Equator

SCP NCP Celestial Meridian CEq Declination

N W E S Horizon Zenith Local Sky

SCP NCP CEq Below the Horizon N S E W Z Visible Half of the Sky

Horizon Measuring Latitude N W E S NCP CEq Zenith Latitude

N S W E Z NCP Equator Z NCP N S W E 40º N Latitude Z NCP North Pole

Zenith W E S N NCP CEq Never Sets Above Horizon for 12 h Above Horizon for > 12 h Above Horizon for < 12 h Never Rises

SCP NCP CEq Ecliptic ~23.5º Obliquity of the Ecliptic

SCP NCP CEq Winter Solstice Summer Solstice Ecliptic

SCP NCP CEq Winter Solstice Summer Solstice Vernal Equinox Autumnal Equinox Ecliptic

W E S N NCP Summer Solstice Vernal & Autumnal Equinoxes Winter Solstice Z CEq

W E S N NCP CEq Summer Solstice Vernal & Autumnal Equinoxes Winter Solstice Z

December March June September

Equinoxes: March 20 & Sept. 22 Northern Spring/Fall Southern Fall/Spring

December 21: Winter Solstice Northern Winter Southern Summer

June 21: Summer Solstice Northern Summer Southern Winter

1 KW/m 2 1 m 2 2 m 2

2000 Dec 21: Winter Solstice 2001 June 21: Summer Solstice 2001 Mar 20: Vernal Equinox 2001 Sept 22: Autumnal Equinox Winter Summer Winter Spring Autumn Spring

Draco Ursa Minor Cepheus Thuban Polaris 2000 AD 2700 BC

Precession of the Equinoxes

Moon at PerigeeMoon at Apogee

New Moon Full Moon Waning Crescent Last Quarter Waning Gibbous Waxing Gibbous Waxing Crescent First Quarter

Sunset Sunrise Midnight Moonset Noon Moonrise Moonrise & Moonset at 1 st Quarter

Sunset Moonrise Sunrise Midnight Noon Moonrise & Moonset at Full Moon

Sunset Sunrise Midnight Moonrise Noon Moonset Moonrise & Moonset at Last Quarter

Sidereal vs. Synodic Months New Moon T=0 d T=27.3 d (Sidereal) T=29.5 d (Synodic)

Penumbra Sun Earth Umbra

Sunlight Uneclipsed Moon Penumbral Eclipse Total Lunar Eclipse Partial Lunar Eclipse

Total Lunar Eclipse (Note the ruddy scattered sunlight) Partial Lunar Eclipse

Sunlight Umbra Penumbra Moon Earth

SCP NCP CEq Ecliptic 4th 1st 2nd 3rd Cross-Quarter Days Winter Solstice Summer Solstice Vernal Equinox Autumnal Equinox

Noon T=0 h T=23 h 56 m 04 s (Sidereal Day) T=24 h (Solar day) Noon Not to Scale Solar & Sidereal Days

Inferior Conjunction Superior Conjunction Earth

Maximum Eastern Elongation Maximum Western Elongation Earth

Conjunction Opposition Earth

Opposition Conjunction Eastern Quadrature Western Quadrature Earth

Mars Retrograde Motion in 1994/ Jan Mar Sept July 4

Saturn & Jupiter 4/ /2000 Saturn Jupiter Mars 11/ /1999 Venus 6-11/1999 Mercury 10-12/1999

SCP NCP Celestial Sphere (Daily E-W Motion) Ecliptic Sphere (Annual W-E Motion 23.5º tilt) Planetary Spheres (Retrograde Motions)

Less Time More Time First Quarter Last Quarter Not to Scale

Earth Deferent Epicycle

Earth Equant Center

Saturn Mars Jupiter Sun Mercury Venus Earth Ptolemaic System

Mars Jupiter Saturn Earth Venus Mercury Sun Solar System

Earth Mars Retrograde Motion

Venus Maximum Eastern Elongation 1 AU D Venus 46º

F1F1 F2F2 Semimajor Axis Center

T=0 d T=10 d T=0 d T=10 d Equal Areas in Equal Times

Jan 10 Jan 11 Jan 12 Jan 13 Jan 19 Jan 18 Jan 15 Jan 16

Io Europa Ganymede Callisto

Ptolemaic System Copernican System

Falling Apple: Changing Speed (gets faster as it falls) Same Direction (always falls down)

Ball Swung around on a String: Same Speed, (in uniform circular motion) Changing Direction (swinging around the circle)

Donut Swung around on a String Force Acceleration

Force = (apple’s mass)  (acceleration due to gravity) Equal and Opposite Force from the Table Net Force is Zero, No Net Motion

M1M1 M2M2 d M1M1 M2M2 2d M1M1 M2M2 d/2

2M 1 M2M2 d M1M1 M2M2 d 2M 2 d

Parabola Hyperbola CircleEllipse Conic Section Curves

Parabola v = v E Hyperbola v>v E Ellipse v C <v<v E Circle v = v C Ellipse v<v C

Columbus, Ohio 40º N: 1280 km/h Arctic Circle 66.5º N: 666 km/h Equator 1670 km/h

6 hours later Towards Sirius

Wavelength ( ) Speed (c) Frequency (f) (# waves/second)

d=1 d=2 d=3 B=1 B=1/9 B=1/4

Doppler Effect in Sound High Pitch (short waves) Low Pitch (long waves)

T=0 s 0 popped 16 unpopped T=35 s 8 popped 8 unpopped Half-Life = 35 sec

Hot Gas Faster Average Speeds Cool Gas Slow Average Speeds

Spectrum Prism White Light Prisms disperse light into its component colors

Continuum Source Continuous Spectrum Absorption-line Spectrum Emission-line Spectrum Cloud of Hydrogen Gas

Hydrogen Helium Oxygen Neon Iron

Continuum Source Cloud of Hydrogen Gas Lamp Light Absorbed by Hydrogen Atoms in the Cloud Lamp emits light at all energies

n=1 (Ground State) n=3 (2 nd excited state) n=2 (1 st excited state) n=4 n=5 Energy Level Diagram of 1 H Continuum n= 

n=1 (Ground State) n=3 (2 nd excited state) n=2 (1 st excited state) n=4 n=5 n=3  2626252524242 Larger Jump = More Energy = Bluer Wavelength n=6

n=1 (Ground State) n=3 (2 nd excited state) n=2 (1 st excited state) n=4 n=5 Photons of all other energies (wavelengths) are ignored and pass on by unabsorbed. n=2  3262625252424 n=6

Spectrum of a Fluorescent Light Mercury

Collecting Area Lens Retina

Simple Refracting Telescope Objective Lens Secondary Lens (Eyepiece) Focus

Primary Mirror Prime Focus Secondary Mirror Cassegrain Focus

238 U 206 Pb 235 U 207 Pb 4.5 Billion Years Ago 238 U 206 Pb 235 U 207 Pb Today 1 half-life6.3 half-lives 50% left 1.2% left

Seismic Station Lower Mantle Core Upper Mantle Crust Seismic Station Surface Waves P-waves S waves P & S waves Earthquake!

Near Side Far Side Two Faces of the Moon Maria Impact Basin Cratered Highlands

A12 A14 A15 A17 A11 A16 L24 L20 L16 Apollo and Luna Landing Sites

Mars Earth Venus Mercury Pluto Neptune Uranus Saturn Jupiter

Pluto Ecliptic

Molecular Hydrogen Metallic Hydrogen “Ice” Rock Jupiter Interior

Molecular Hydrogen Metallic Hydrogen “Ice” Rock Saturn Interior

Interiors of Uranus & Neptune Uranus Neptune Rocky Cores Slushy “Ice”Mantles Molecular Hydrogen

Metallic Hydrogen Jupiter Saturn Uranus Neptune Earth

S S P P Star’s spectrum shifts redward Star’s spectrum shifts blueward