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Free "Astronomy 101" course

Are you interested in learning about astronomy?

If so, here's a set of about 300 short videos that will take you through the basics of our solar system.

Enjoy, and we hope you learn something!

Lesson 1: Class introduction: Me encouraging to stop looking down at your phone, and up at the sky

Lesson 2: Class introduction: More encouragment to look up at the sky, be a better camper, themes in this class

Lesson 3: Class introduction: look at the calendar, and where grades will come from

Lesson 4: A taste of ASTR-101 Part I: colors in the sky, Uranus, moon front and back

Lesson 5: A taste of ASTR-101 Part II: dark side of moon, and Mars

Lesson 6: A taste of ASTR-101 Part III: going to Mars, comets, and telescopes

Lesson 7: A taste of ASTR-101 Part IV: the night sky, sizes of objects in the sky

Lesson 8: A taste of ASTR-101 Part V: Death Star/Mimas, Star of Bethlehem, Neptune's orbit

Lesson 9: Some astronomy definitions: difference between astronomy, astophysics, and astrology

Lesson 10: Some astronomy definitions: contellation art, Orion, Pollux/Castor, astrology in our lives

Lesson 11: Solar system start: first look at the solar system and basic structure and motion

Lesson 12: Solar system start: names of planets, mother and nachos or pizza,orbit vs rotation times

Lesson 13: Solar system start: finish orbit vs. rotation times

Lesson 14: The earth's tilt and seasons: why we have seasons: the earth's tilt and 4 key positions in its orbit

Lesson 15: The earth's tilt and seasons: tilt map of all planets

Lesson 16: The earth's tilt and seasons: Four key positions of earth around sun, and looking at light rays of first 2

Lesson 17: The earth's tilt and seasons: Four key positions of earth around sun, label dates and solstice or equinox and season

Lesson 18: The earth's tilt and seasons: northern and southern most reach of the sun's direct rays

Lesson 19: The earth's tilt and seasons: Annual motion of the sun's direct rays and defining the Tropics of Cancer and Capricorn

Lesson 20: The earth's tilt and seasons: Sun's setting direction during the year.

Lesson 21: The earth's tilt and seasons: Seasonal constellations seen overhead at midnight during the year.

Lesson 22: The earth's tilt and seasons: Astrological stories of Orion and Virgo.

Lesson 23: The earth's tilt and seasons: My trip to Australia and the Tropic of Capricorn.

Lesson 24: The solar system (and beyond): what you'll encounter out there.

Lesson 25: The solar system: Distances and the astronomical unit.

Lesson 26: The solar system: Astronomical unit, light year, parsec.

Lesson 27: The solar system: Han Solo and the Kessel-run quote.

Lesson 28: The solar system: discussion of Han Solo and the Kessel-run quote.

Lesson 29: The solar system: Beyond our galaxy and zooming in on the Andromeda Galaxy

Lesson 30: The solar system (and beyond): Sizes of things out there (planets to Stars and some distances). CVS receipt as the A.U.

Lesson 31: The solar system: Great Youtube videos on the proper relative size of things in the solar system.

Lesson 32: Gravity: What holds the planets in their orbits?

Lesson 33: Gravity: Law of gravity and setting up an orbit (balance between force of gravity and speed).

Lesson 34: Gravity: Newton's first thoughts on gravity (Newton's Cannon).

Lesson 35: Gravity: PHeT gravity simulator, earth/sun and earth/sun/moon

Lesson 36: Gravity: Jab at astrology Part I: the newborn and hospital worked winning the lottery.

Lesson 37: Gravity: Jab at astrology Part II: gravity on the newborn due to Neptune and the hospital equipment.

Lesson 38: Gravity: Jab at astrology Part III: Computing the force of gravity due to Neptune and the hospital equipment.

Lesson 39: The night sky: being a better camper and first patterns in the night sky (Big Dipper and Polaris).

Lesson 40: The night sky: starting with Polaris and the Big Dipper.

Lesson 41: The night sky: existence of Polaris using Stellarium.

Lesson 42: The night sky: different orientations of the Big Dipper to find Polaris.

Lesson 43: The night sky: practice finding the Big Dipper (and possibly Polaris).

Lesson 44: The night sky: list of things to find (Polaris, Big Dipper, Arcturas, Spica, Pollux/Castor, Antares, Cassiopeia, Scorpius/Teapot).

Lesson 45: The night sky: Star hopping from the Big Dipper to find Arcturas, Spica, Pollux/Castor.

Lesson 46: The night sky: Star hopping in Stellarium, from the Big Dipper to find Arcturas, Spica, Pollux/Castor.

Lesson 47: The night sky: Big stars, and angular distances and using your hand to measure them.

Lesson 48: The night sky: The "other side" of Polaris to see Cassiopeia and the location of the Andromeda Galaxy.

Lesson 49: The night sky: Cassiopeia in Stellarium.

Lesson 50: The night sky: Contellations vs. Asterisms.

Lesson 51: The night sky: Scorpius and the Teapot and the direction to the center of our galaxy.

Lesson 52: The night sky: South of the equator. Is there a "south star?"

Lesson 53: The night sky: History of Polaris. Finding it if foggy, times of slavery, introduction to latitude.

Lesson 54: The night sky: Using polaris and how far to bend your neck to see it.

Lesson 55: The night sky: Polaris's altitude vs your latitude.

Lesson 56: The night sky: Polaris/latitude wrap-up and declination of other stars (Dubhe, Vega, Spica, Arcturas).

Lesson 57: The sky's motion: do the sun, moon, stars, planets move?

Lesson 58: The sky's motion: Actual motion

Lesson 59: The sky's motion: Apparent motion: A380 landing speed and motion of the Big Dipper.

Lesson 60: The sky's motion: Apparent motion on a merry-go-round

Lesson 61: The sky's motion: star trails with CL........ICK of an SLR camera.

Lesson 62: The sky's motion: Extreme star trails at the north pole and equator.

Lesson 63: Celestial Sphere: definition part I

Lesson 64: Celestial Sphere: definition part II

Lesson 65: Celestial Sphere: nice graphics in "Rotating Sky Explorer."

Lesson 66: Celestial Sphere: The horizon

Lesson 67: Celestial Sphere: uses of it.

Lesson 68: Celestial Sphere: rising and setting of stars and polaris.

Lesson 69: Celestial Sphere: Circumpolar stars, starts that never rise, and different visible vs invisible timing of stars.

Lesson 70: Celestial Sphere: Worksheet Part I.

Lesson 71: Celestial Sphere: Worksheet Part II.

Lesson 72: Celestial Sphere: Worksheet Part III.

Lesson 73: Celestial Sphere: The Sun on the celestial sphere and the hardest figure in all of astronomy.

Lesson 74: Celestial Sphere: The hardest figure in all of astronomy and the Sun on the celestial sphere.

Lesson 75: Celestial Sphere: Orion and Mintaka (an E/W beacon).

Lesson 76: Celestial Sphere: The size of Betelgeuse compared to our solar system.

Lesson 77: Celestial Sphere: Let's draw our own!

Lesson 78: Celestial Sphere: Sun moving on the Celestial sphere and a hint of the seasons.

Lesson 79: The moon: Basic facts

Lesson 80: The moon: Some basic pictures

Lesson 81: The moon: The backside we never see

Lesson 82: The moon: Setup for why there is no dark side

Lesson 83: The moon: Seeing it appear in front of the earth

Lesson 84: The moon: why there is no dark side

Lesson 85: The moon: Why we see the same side of it

Lesson 86: The moon: A model for why there can't be a dark side

Lesson 87: The moon: Break in its orbit

Lesson 88: The moon: Is the moon that far from us?

Lesson 89: The moon: Introduction to tidal locking

Lesson 90: The moon: Tidal locking and its orbit

Lesson 91: The moon: Tidal locking and warping of rocks

Lesson 92: The moon: Tidal forces on rocks and water

Lesson 93: The moon: Tidal locking and energy losses

Lesson 94: The moon: Excellent videos on tidal locking

Lesson 95: The moon: where is came from

Lesson 96: The moon: evidence of where it came from

Lesson 97: The moon: more evidence of where it came from

Lesson 98: The moon: origins in centrifugal force and fission

Lesson 99: The moon: origins in capture and condensation

Lesson 100: The moon: origins in a big cosmic collision

Lesson 101: The moon: summary of its origin

Lesson 102: Craters: Introduction

Lesson 103: Craters: A field of craters on the moon

Lesson 104: Craters: Geosleuthing a crater field on the moon

Lesson 105: The moon: its near and far sides in terms of craters

Lesson 106: Eclipses: sometimes this happens

Lesson 107: Eclipses: finish introducing them

Lesson 108: Eclipses: What you would see

Lesson 109: Eclipses: going to a total eclipse

Lesson 110: Eclipses: why no eclipse once a month

Lesson 111: Eclipses: Formal discussion p1

Lesson 112: Eclipses: Formal discussion p2

Lesson 113: Eclipses: Formal discussion p3

Lesson 114: Eclipses: Formal discussion p4

Lesson 115: Eclipses: Formal discussion p5

Lesson 116: Phases of the moon: Introduction

Lesson 117: Phases of the moon: more introduction

Lesson 118: Phases of the moon: First 3 phases

Lesson 119: Phases of the moon: Nice graphic

Lesson 120: Phases of the moon: Last of the phases

Lesson 121: Phases of the moon: Earthshine

Lesson 122: The Sun: Introduction to the sun

Lesson 123: The Sun: more on an introduction

Lesson 124: The Sun: why do we draw the sun so happy?

Lesson 125: The Sun: The sun in Australia

Lesson 126: The Sun: Fusion in the interior

Lesson 127: The Sun: Proton-proton chain p1

Lesson 128: The Sun: Proton-proton chain p2

Lesson 129: The Sun: Proton-proton chain p3

Lesson 130: The Sun: The solar wind p1

Lesson 131: The Sun: The solar wind p2

Lesson 132: The Sun: Comets

Lesson 133: The Sun: Comet tails p1

Lesson 134: The Sun: Comet tails p2

Lesson 135: The Sun: Comet tails p3

Lesson 136: The Sun: Evidence of the solar wind

Lesson 137: The Sun: More solar wind evidence

Lesson 138: The sun: introduction to Auroras

Lesson 139: The sun: introduction to Auroras (current and wires)

Lesson 140: The sun: Auroras and mag field outside of a wire

Lesson 141: The sun: Auroras and now a wire makes a magnetic field

Lesson 142: The sun: Auroras moving charges make a magnetic field

Lesson 143: The sun: the Earth's magnetic field

Lesson 144: The sun: the Earth's magnetic field like a bar magnet

Lesson 145: The sun: Auroras how earth's magnetic field deflects the solar wind

Lesson 146: The sun: Auroras and where the light comes from

Lesson 147: The sun: Auroras and where the light comes from (with sound)

Lesson 148: The sun: Auroras on other planets

Lesson 149: Solar wind: wrap up worksheet

Lesson 150: Solar wind: wrap up worksheet (part 2)

Lesson 151: Active geology: maps of earthquakes, volcanos, rock ages, and elevations

Lesson 152: Active geology: subduction zones

Lesson 153: Active geology: Barringer and wolf craters

Lesson 154: Active geology: crater formation

Lesson 155: Active geology: going to Mars

Lesson 156: Quick inventory of questions answered

Lesson 157: Light: the great astronomy messenger

Lesson 158: Light: map of earth at night

Lesson 159: Light: light pollution

Lesson 160: Light: if the skies were really dark...

Lesson 161: Light: dark skies and the structure of our galaxy

Lesson 162: Light: what is light? Photon and wave

Lesson 163: Light: intro to wave frequency

Lesson 164: Light: wave frequency, Hz and all

Lesson 165: Light: frequency into via sound waves

Lesson 166: Light: hear some different frequencies

Lesson 167: Light: wavelength and amplitude

Lesson 168: Light: where photons come from

Lesson 169: Light: where light waves come from

Lesson 170: Light: Blue comet tails based on photons and waves

Lesson 171: Light: Color

Lesson 172: Laws of light: notation on what happens when light encounters something

Lesson 173: Laws of light: the law of reflection

Lesson 174: Laws of light: law of reflection visuals

Lesson 175: Laws of light: retroreflectors and the moon

Lesson 176: Laws of light: law of refraction

Lesson 177: Laws of light: law of refraction visuals

Lesson 178: Laws of light: the index of refraction

Lesson 179: Laws of light: snell's law for refraction

Lesson 180: Laws of light: refraction trends (bending toward or away)

Lesson 181: Laws of light: everyday light effects

Lesson 182: Laws of light: lie of the sunset

Lesson 183: Laws of light: why stars twinkle

Lesson 184: Laws of light: twinkling stars in Stellarium

Lesson 185: Laws of light: model of twinkling stars

Lesson 186: Laws of light: Minute Physics on twinkling stars

Lesson 187: Laws of light: Jurassic Park and the law of reflection

Lesson 188: Laws of light: setup for how mirages occur

Lesson 189: Laws of light: air layers for mirages

Lesson 190: Laws of light: path of a sun ray with mirages

Lesson 191: Laws of light: wrap up how mirages occur

Lesson 192: Laws of light: into to why the sky is blue

Lesson 193: Laws of light: light waves and the blue sky

Lesson 194: Laws of light: blue light in nitrogen and oxygen

Lesson 195: Laws of light: charges in molecules

Lesson 196: Laws of light: "Gravity" clip of upper atmosphere

Lesson 197: Laws of light: how air filers blue of out of white light

Lesson 198: Laws of light: conclusions on why the sky is blue

Lesson 199: Laws of light: why sunsets are red

Lesson 200: Laws of light: silent conclusion on blue sky and red sunset

Lesson 201: Laws of light: why the red moon in a lunar eclipse

Lesson 202: Laws of light: when sunsets are too red

Lesson 203: Laws of light: dispersion

Lesson 204: Laws of light: how index of refraction depends on wavelength

Lesson 205: Laws of light: define dispersion

Lesson 206: Laws of light: how rainbows form part 1

Lesson 207: Laws of light: how rainbows form part 2

Lesson 208: Laws of light: how rainbows form part 3

Lesson 209: Laws of light: why clouds are white

Lesson 210: Laws of light: where the greenflash comes from

Lesson 211: Nebular Hypothesis: Introduction

Lesson 212: Nebular Hypothesis: Introduction (more)

Lesson 213: Nebular Hypothesis: What it must describe

Lesson 214: Nebular Hypothesis: Physics needed

Lesson 215: Nebular Hypothesis: Dust and gravity

Lesson 216: Nebular Hypothesis: Something happened

Lesson 217: Nebular Hypothesis: consequences of spinning

Lesson 218: Nebular Hypothesis: A spinning ice skater

Lesson 219: Nebular Hypothesis: how the solar system became flat

Lesson 220: Nebular Hypothesis: Minute Physics on how the solar system became flat

Lesson 221: Nebular Hypothesis: How the sun may have ignited

Lesson 222: Nebular Hypothesis: how the Frost Line formed

Lesson 223: Nebular Hypothesis: formation of planetoids

Lesson 224: Nebular Hypothesis: some visuals

Lesson 225: Nebular Hypothesis: Wrapup 01

Lesson 226: Nebular Hypothesis: Wrapup 02

Lesson 227: Nebular Hypothesis: Wrapup 03

Lesson 228: Nebular Hypothesis: Wrapup 04

Lesson 229: Nebular Hypothesis: Wrapup 05

Lesson 230: Planets: Introduction and teaching plan

Lesson 231: Planets: Mercury introduction

Lesson 232: Planets: Mercury phases

Lesson 233: Planets: Mercury composition

Lesson 234: Planets: Mercury its big core

Lesson 235: Planets: Mercury why the large core

Lesson 236: Planets: Mercury magnetic field

Lesson 237: Timing: solar

Lesson 238: Timing: solar and star timing

Lesson 239: Timing: Sidereal timing part 01

Lesson 240: Timing: Sidereal timing part 02

Lesson 241: Planets: Mercury and timing of its orbit

Lesson 242: Planets: Mercury orbit and a summary

Lesson 243: Planets: Mercury and tidal locking to the sun

Lesson 244: Planets: Mercury introduction to the Doppler Effect

Lesson 245: Planets: Mercury the Doppler Effect--moving toward and away

Lesson 246: Planets: Mercury the Doppler Effect bouncing radio waves off of it

Lesson 247: Planets: Mercury and the Arecibo Observatory

Lesson 248: Planets: Mercury wrap up

Lesson 249: Venus: an introduction (01)

Lesson 250: Venus: an introduction (02)

Lesson 251: Venus: very hot and other facts

Lesson 252: Venus: an introduction and the "Venus Equation"

Lesson 253: Venus: why it's so hot

Lesson 254: Rocks and Infrared radiation

Lesson 255: Venus and the greenhouse effect

Lesson 256: Venus and the greenhouse effect simulation

Lesson 257: CO2 concentration on Earth wrap up

Lesson 258: CO2 concentration wrap up with Al Gore

Lesson 259: Tracking a CO2 molecule in the Carbon Cycle

Lesson 260: Carbon Cycle wrap up

Lesson 261: Compare temperatures on Earth and Venus with and without CO2

Lesson 262: Comparing Mercury Venus Earth and Mars

Lesson 263: Mars: Introduction and quick facts

Lesson 264: Mars: Terraforming it?

Lesson 265: Mars: Water once flowed

Lesson 266: Mars: Introduction to the Alan Hills meteor (01)

Lesson 267: Mars: Alan Hills meteor (02)

Lesson 268: Mars compared to other planets (too cold)

Lesson 269: Mars: why all of the intrigue (P01)

Lesson 270: Mars: why all of the intrigue (P02)

Lesson 271: Mars: speeds needed to get there

Lesson 272: Getting to Mars at 18000 mph

Lesson 273: Mars: getting there by coasting

Lesson 274: So you want to land on Mars huh?

Lesson 275: Mars: landing the Pathfinder Rover

Lesson 276: Mars: landing the Curiosity Rover

Lesson 277: Landing on Mars summary and Minute Physics reference

Lesson 278: Mars: how its atmosphere got the way it is

Lesson 279: Introduction to Jupiter (01)

Lesson 280: Introduction to Jupiter (02)

Lesson 281: Intro to Jupiter and the Galieo mission

Lesson 282: Jupiter and the Galileo mission

Lesson 283: Using Jupiter for a gravity assist

Lesson 284: Using Jupiter to measure the speed of light (Romer)

Lesson 285: Jupiter and its moons

Lesson 286: Juipter's moon Io: introduction

Lesson 287: Juipter's moon Io being tortured by Jupiter's tidal forces

Lesson 288: Juipter's moon Io and moving through Jupiter's magnetic field

Lesson 289: Juipter's moon Io and the flux and plasma tubes

Lesson 290: Saturn's moon Europa and its minerals/water/and heat

Lesson 291: Wrap up on Saturn's moon Europa

Lesson 292: Some views of Saturn and why it has rings

Lesson 293: Saturns rings and the Roche limit

Lesson 294: Closing thoughts for Astronomy 101