logging in or signing up Presentation2 Octavio Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 69 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: August 14, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Astronomy Stuff: Astronomy Stuff Some Selected Topics How Big is the Universe?: How Big is the Universe? REALLY BIG! Our Position and Motion in the Heavens: Our Position and Motion in the Heavens Are we ever sitting still? : Are we ever sitting still? Earth rotates on axis: andgt; 1,000 km/hr Earth orbits Sun: andgt; 100,000 km/hr Solar system moves among stars: ~ 70,000 km/hr Milky Way rotates: ~ 800,000 km/hr Milky Way moves in Local Group Universe expands Planets in Order and To Scale: Planets in Order and To Scale Build a scale model of solar system http://www.exploratorium.edu/ronh/solar_system/ Basic Properties of the Sun: Basic Properties of the Sun Radius is 100 times that of the Earth. 30,000 Earth’s would cover the surface. 1 million Earths would fit inside! It is a million times more massive than Earth 99.9% of mass of solar system Luminosity is 400 trillion trillion Watts. The Milky Way Galaxy: The Milky Way Galaxy diameter of disk = 100,000 l.y. (30,000 pc) number of stars = 200 billion thickness of disk = 1,000 l.y. (300 pc) Sun is in disk, 28,000 l.y. out from center Slide8: Planets all orbit in same direction and nearly in same plane Planetary Motion Johannes Kepler (1571-1630): Johannes Kepler (1571-1630) Trained as a mathematician and theorist. Needed accurate data to make mathematical model of the solar system What are Kepler’s three laws of planetary motion?: What are Kepler’s three laws of planetary motion? Kepler’s First Law: Kepler’s First Law Each planet’s orbit around the Sun is an ellipse, with the Sun at one focus. Slide12: An ellipse looks like an elongated circle What is an ellipse? Eccentricity of an Ellipse: Eccentricity of an Ellipse Kepler’s Second Law: Kepler’s Second Law A planet moves along its orbit with a speed that changes in such a way that a line from the planet to the Sun sweeps out equal areas in equal intervals of time. Kepler’s Third Law: Kepler’s Third Law The ratio of the cube of a planet’s average distance (a) from the Sun to the square of its orbital period (P) is the same for each planet. a3 / P2 = 1 a3 = P2 So what is with the Zodiac Signs?: So what is with the Zodiac Signs? Intro to the Sun Signs Annual Motion: Annual Motion What is the cause of the seasons on Earth?: What is the cause of the seasons on Earth? The Cause of the Seasons : The Cause of the Seasons Note apparent change in altitude of Sun. Direct light causes more heating. : Direct light causes more heating. The “altitude” of the Sun impacts both how much energy is received on Earth and the duration of daylight.: The 'altitude' of the Sun impacts both how much energy is received on Earth and the duration of daylight. Axis tilt causes uneven heating by sunlight throughout the year. : Axis tilt causes uneven heating by sunlight throughout the year. Seasons Clip Sun’s Motion Across the Sky: Sun’s Motion Across the Sky Why are the warmest days typically a month after the beginning of summer?: Why are the warmest days typically a month after the beginning of summer? Typically…: Typically… It takes a while for the Earth’s surface to cool or to warm up. The hottest days of summer are about a month or two after the summer solstice. Likewise, the coldest days are about a month or so after the winter solstice. What would seasons be like if…: What would seasons be like if… The Earth had no tilt? The Earth’s axis lay on the ecliptic plane? What is the Earth’s cycle of precession?: What is the Earth’s cycle of precession? Precession of the Earth: Precession of the Earth Earth’s axis precesses like the axis of a spinning top once very 26,000 years. Changes in Axis Tilt: Changes in Axis Tilt Small gravitational tugs from other bodies in solar system cause Earth’s axis tilt to vary between 22° and 25° Cycles every 41,000 years What do you notice going on here?: What do you notice going on here? The Moon What is a constellation?: What is a constellation? A Constellation is…: A Constellation is… A region in the sky. Thought QuestionThe brightest stars in a constellation…: Thought Question The brightest stars in a constellation… All belong to the same star cluster. All lie at about the same distance from Earth. May actually be quite far away from each other. The brightest stars in a constellation…: The brightest stars in a constellation… All belong to the same star cluster. All lie at about the same distance from Earth. May actually be quite far away from each other. Constellations: Constellations Constellation stars need not be close together in space. Why do we see phases of the Moon?: Why do we see phases of the Moon? Why do we see phases?: Why do we see phases? Phase Clip What are the different Moon phases?: What are the different Moon phases? Phases of the Moon: Phases of the Moon The Sun & Milky Way: The Sun andamp; Milky Way You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Presentation2 Octavio Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 69 Category: Entertainment License: All Rights Reserved Like it (0) Dislike it (0) Added: August 14, 2007 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Astronomy Stuff: Astronomy Stuff Some Selected Topics How Big is the Universe?: How Big is the Universe? REALLY BIG! Our Position and Motion in the Heavens: Our Position and Motion in the Heavens Are we ever sitting still? : Are we ever sitting still? Earth rotates on axis: andgt; 1,000 km/hr Earth orbits Sun: andgt; 100,000 km/hr Solar system moves among stars: ~ 70,000 km/hr Milky Way rotates: ~ 800,000 km/hr Milky Way moves in Local Group Universe expands Planets in Order and To Scale: Planets in Order and To Scale Build a scale model of solar system http://www.exploratorium.edu/ronh/solar_system/ Basic Properties of the Sun: Basic Properties of the Sun Radius is 100 times that of the Earth. 30,000 Earth’s would cover the surface. 1 million Earths would fit inside! It is a million times more massive than Earth 99.9% of mass of solar system Luminosity is 400 trillion trillion Watts. The Milky Way Galaxy: The Milky Way Galaxy diameter of disk = 100,000 l.y. (30,000 pc) number of stars = 200 billion thickness of disk = 1,000 l.y. (300 pc) Sun is in disk, 28,000 l.y. out from center Slide8: Planets all orbit in same direction and nearly in same plane Planetary Motion Johannes Kepler (1571-1630): Johannes Kepler (1571-1630) Trained as a mathematician and theorist. Needed accurate data to make mathematical model of the solar system What are Kepler’s three laws of planetary motion?: What are Kepler’s three laws of planetary motion? Kepler’s First Law: Kepler’s First Law Each planet’s orbit around the Sun is an ellipse, with the Sun at one focus. Slide12: An ellipse looks like an elongated circle What is an ellipse? Eccentricity of an Ellipse: Eccentricity of an Ellipse Kepler’s Second Law: Kepler’s Second Law A planet moves along its orbit with a speed that changes in such a way that a line from the planet to the Sun sweeps out equal areas in equal intervals of time. Kepler’s Third Law: Kepler’s Third Law The ratio of the cube of a planet’s average distance (a) from the Sun to the square of its orbital period (P) is the same for each planet. a3 / P2 = 1 a3 = P2 So what is with the Zodiac Signs?: So what is with the Zodiac Signs? Intro to the Sun Signs Annual Motion: Annual Motion What is the cause of the seasons on Earth?: What is the cause of the seasons on Earth? The Cause of the Seasons : The Cause of the Seasons Note apparent change in altitude of Sun. Direct light causes more heating. : Direct light causes more heating. The “altitude” of the Sun impacts both how much energy is received on Earth and the duration of daylight.: The 'altitude' of the Sun impacts both how much energy is received on Earth and the duration of daylight. Axis tilt causes uneven heating by sunlight throughout the year. : Axis tilt causes uneven heating by sunlight throughout the year. Seasons Clip Sun’s Motion Across the Sky: Sun’s Motion Across the Sky Why are the warmest days typically a month after the beginning of summer?: Why are the warmest days typically a month after the beginning of summer? Typically…: Typically… It takes a while for the Earth’s surface to cool or to warm up. The hottest days of summer are about a month or two after the summer solstice. Likewise, the coldest days are about a month or so after the winter solstice. What would seasons be like if…: What would seasons be like if… The Earth had no tilt? The Earth’s axis lay on the ecliptic plane? What is the Earth’s cycle of precession?: What is the Earth’s cycle of precession? Precession of the Earth: Precession of the Earth Earth’s axis precesses like the axis of a spinning top once very 26,000 years. Changes in Axis Tilt: Changes in Axis Tilt Small gravitational tugs from other bodies in solar system cause Earth’s axis tilt to vary between 22° and 25° Cycles every 41,000 years What do you notice going on here?: What do you notice going on here? The Moon What is a constellation?: What is a constellation? A Constellation is…: A Constellation is… A region in the sky. Thought QuestionThe brightest stars in a constellation…: Thought Question The brightest stars in a constellation… All belong to the same star cluster. All lie at about the same distance from Earth. May actually be quite far away from each other. The brightest stars in a constellation…: The brightest stars in a constellation… All belong to the same star cluster. All lie at about the same distance from Earth. May actually be quite far away from each other. Constellations: Constellations Constellation stars need not be close together in space. Why do we see phases of the Moon?: Why do we see phases of the Moon? Why do we see phases?: Why do we see phases? Phase Clip What are the different Moon phases?: What are the different Moon phases? Phases of the Moon: Phases of the Moon The Sun & Milky Way: The Sun andamp; Milky Way