Bell-Ringer 1. Write out what you know about astronomy. 2. How does the size of the Sun compare to the size of the Earth? 3. What types of tools do astronomers use? Earth s Address 1
Earth Solar System 2
Milky Way Galaxy 3
Milky Way Galaxy 4
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The Sun-Earth-Moon System Tools of Astronomy: Have you ever used a magnifying lens to read fine print? If so, you have used a tool that gathers and focuses light. Astronomers use telescopes to gather and focus light from distant objects. 6
Tools of Astronomy: What is radiation? Astronomers study electromagnetic radiation. Electromagnetic radiation includes visible light, infrared and ultraviolet radiation, radio waves, microwaves, X-rays, and gamma rays 7
Parts of the wave amplitude crest rest position trough wavelength 15 Wavelength measures the distance between two equivalent parts of a wave The distance from the crest of one wave to the crest of the next wave is called the wavelength. In longitudinal waves, the wavelength is the distance between two compressions or two rarefactions. The distance between two successive identical parts of a wave. 16 8
Frequency measures the rate of vibrations The frequency of a wave is the number of full wavelengths that pass a point in a given time interval. Measures how rapidly vibrations occur in the medium Symbol for frequency is f. 17 Frequency measures the rate of vibrations SI unit of frequency is hertz (Hz) Unit named after Heinrich Hertz, who in 1888 became the first person to experimentally demonstrate the existence of electromagnetic waves One vibration per second is 1 Hz 18 9
Check for Understanding In what ways do we use electromagnetic radiation on a daily basis? 10
Wavelength & Frequency C = λf C = speed of light Speed of light C = 300,000,000 m/s C = 186,000 miles per second C = 671 million miles per hour 11
Telescopes: Objects in space emit radiation in all proportions of the electromagnetic spectrum. Telescopes: Telescopes give us the ability to observe wavelengths beyond what the human eye can detect. 12
China Radio Telescope: 4m-Blanco Light Telescope: 13
Hubble space telescope : Mars Landing Rover 14
Voyager space probe Jupitor from earth based telescope 15
Jupiter from Hubble Jupiter from Voyager 16
Telescopes: The pupil of your eye has a diameter of up to 7mm when it is adapted to darkness. Telescopes: If you compared the ratio of head size to eye size of a great horned owl and humans, your eyes would be the size of grapefruits. 17
Telescopes: Similarly, a telescopes opening, called an aperture, might be as large as 10 meters in diameter. The larger the aperture, the more light or electromagnetic radiation can be gathered or collected. Benefits of Telescopes: Telescopes can detect radiation beyond what the human eye can detect. The larger aperture allows more radiation to be gathered so objects that are too dim to see can be recorded. 18
Benefits of Telescopes: Another way that the telescope surpasses the human eye is with the aid of cameras, or other imaging devices to create time exposures. Telescopes can detect objects that are too faint for the human eye to see. Time Exposure: 19
Time Exposure: 20
Refracting Telescope Reflecting Telescope 21
Reflecting Telescope Interferometry: Interferometry is a technique that uses the images from several telescopes to produce a single image. By combining multiple images, astronomers can create detailed images that could only be achieved from larger telescopes. 22
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Bell-Ringer What proof is there that we have landed on the moon? 25
Refracting Telescope Reflecting Telescope 26
Interferometry: Interferometry is a technique that uses the images from several telescopes to produce a single image. By combining multiple images, astronomers can create detailed images that could only be achieved from larger telescopes. 27
Reflector Array Exploring the Moon Astronomers have learned much about the moon from observations with telescopes. Most of our knowledge about the moon comes from explorations by space probes and landings by astronauts. 28
Exploring the Moon The first step toward reaching the moon was in 1957 when the Soviet Union launched the first artificial satellite, Sputnik I 4 Years later, Soviet Cosmonaut Yuri A. Gagarin became the first human in space. Sputnik 1 29
Exploring the Moon Exploring the Moon In 1961, Alan B. Shepard, Jr. was the first American in space. July 20, 1969, the Apollo 11 mission landed Neil Armstrong and Edwin Buzz Aldrin on the Moon. 30
Exploring the Moon Exploring the Moon 31
Exploring the Moon The last mission of the Apollo program was Apollo 17 - December 7, 1972 Eugene Gene Cernan, Commander of Apollo 17, was the last person to set foot on the Moon. No person has set foot on the Moon since 1972. 32
The Lunar Surface: Albedo is the amount of sunlight that is reflected from an objects surface. The albedo of the moon is very low. 7-8% Earth s albedo is 31% 33
The Lunar Surface: The Lunar Surface: Lunar highlands are heavily cratered regions of the Moon that are light in color and mountainous. Other regions called maria are dark, smooth planes. 3km lower in elevation 34
A Trip to the Moon: 1902 Silent Film 35
The Lunar Surface: Craters on the Moon, called impact craters, formed when objects from space crashed into the lunar surface. The Lunar Surface: 36
The Lunar Surface: The material blasted out during impacts falls back to the Moon s surface as ejecta. Some craters have long trails of ejecta, called rays, that radiate outward from the impact site. Fresh ejecta 37
The Lunar Surface: Rilles are meandering, valleylike structures that might be collapsed lava tubes. Lunar Properties Our moon is unique among all the moons in the solar system. It is one of the largest moons compared to the mass of the planet it orbits. It is solid and rocky, in contrast with the icy composition of most other moons. 38
Lunar Properties Our moon orbits very far from Earth relative to other moons and the planets they orbit. Composition The moon is made up of minerals similar to those found on Earth (mostly silicates). The maria are mostly basalt, but unlike basalt on earth, they contain no water. 39
Far Side Far Side 40
History of the Moon The lunar surface is about the same age of Earth (3.8-4.6 billion years) We know this by radiometric dating of rocks from the surface. Based on the frequency of impact craters, scientists theorize the Moon was heavily bombarded during its first 800 million years. History of the Moon A layer of loose ground up rock (regolith) several meters thick formed on the surface of the moon due to heavy bombardment of asteroids. 41
Layered Structure Scientists infer from seismic data collected by seismographs left on the Moon that the Moon has a layered structure, similar to Earth. Layered Structure 42
Formation of Maria After the period of heavy bombardment, lava welled up from the Moon s interior and in the large impact basins. This created the dark smooth plains of the maria that we see today. Tectonics The moon is no longer tectonically active (No volcanoes, no magnetic field) However, the moon experiences an annual moonquake. 43
Giant Impact Theory There are several theories to explain how the moon came into existence. The most accepted theory by astronomers is the Giant Impact Theory 44
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Driving Question Why is there no change of season at the equator? Effects of Earth s Tilt: Earth is tilted 23.5 relative to the ecliptic plane 46
Effects of Earth s Tilt: The ecliptic plane is the plane of Earth s orbit. Effects of Earth s Tilt Earth s orbit around the Sun and the tilt of Earth contributes to the changes of season we are familiar with. 47
Effects of Earth s Tilt: At a solstice, the Sun is overhead at its farthest distance either north or south of the Equator. Effects of Earth s Tilt: At an equinox, Earth s axis is perpendicular to the Sun s rays and at noon the sun is directly overhead at the equator. 48
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Lunar Motions Synchronous rotation explains why only one side of the moon always faces Earth. It is the state at which the Moon s orbital period and rotation periods are equal. The Moon s orbital period (lunar month) is 27.3 days. 50
Today: Turn in any worksheets: Eclipse simulation from Friday. Lunar Phases Lunar Phases Quiz Tomorrow! 51
Tides: The Sun and the Moon both contribute to Earth s tides by their gravitational pull which creates bulges of ocean water. Tides are observed every 12 hours as the Earth rotates and the Moon orbits the Earth. 52
Spring and Neap Tides: Solar Eclipse A solar eclipse occurs when the Moon passes directly between the Sun and the Earth. 53
Types of Solar Eclipses Depending on whether the Moon is at perigee or apogee during a solar eclipse, we may experience a total eclipse or an annular eclipse 54
Types of Solar Eclipses A total eclipse occurs when the moon is lined up directly between the Earth and the Sun while at Perigee. Types of Solar Eclipses An annular eclipse occurs when the moon is lined up directly between the Earth and the Sun while at Apogee During an annular eclipse, a ring of light is visible. 55
Lunar Eclipse A lunar eclipse occurs when the Moon passes through Earth s Shadow 56
ECLIPSE CALANDER May 25, 2013 - Penumbral Lunar Eclipse. The eclipse will be visible throughout most of North America, South America, western Europe, and western Africa. 57
ECLIPSE CALANDER August 21, 2017 - Total Solar Eclipse. This is a rare, once-in-a-lifetime event for viewers in the United States. The last total solar eclipse visible in the United States occurred in 1979 and the next one will not take place until 2024. The path of totality will begin in the Pacific Ocean and travel through the center of the United States. The total eclipse will be visible in parts of Oregon, Idaho, Wyoming, Nebraska, Missouri, Kentucky, Tennessee, North Carolina, and South Carolina before ending in the Atlantic Ocean. A partial eclipse will be visible in most of North America and parts of northern South America. 58
Foucault Pendulum 59
Foucault Pendulum For the Test: What you need to know: Types of electromagnetic radiation Types of telescopes Surface features of the moon Theory of the formation of the moon Motion of the earth and moon around the sun. Solstices, equinoxes, and eclipses Phases of the moon 60
Review: 1. Linking telescopes to improve the detail in the images obtained is called. Interferometry Review: 2. A telescope that uses curved lenses to focus visible light is called a(an) Refracting Telescope 61
Review: 3. The Moon s is the amount of sunlight that its surface reflects. Albedo Review: 4. The is the point in the Moon s orbit when it is farthest from Earth Apogee 62
Review: 5. Loose, ground-up rock, such as the layer covering much of the surface of the moon. Regolith Review: 6. In the following diagram, would it be winter or summer in the northern hemisphere? Summer 63
Review: 7. The far side of the moon has many more than the near side? a) maria b) solstices c) impact craters d) equinoxes Review: 7. The far side of the moon has many more than the near side? a) maria b) solstices c) impact craters d) equinoxes 64
Review: 8. A occurs when the Moon passes directly between the sun and the Earth. a) Solstice b) Solar Eclipse c) Equinox d) Lunar Eclipse Review: 8. A occurs when the Moon passes directly between the sun and the Earth. a) Solstice b) Solar Eclipse c) Equinox d) Lunar Eclipse 65
Review: 9. Who was the first person to set foot on the moon? a) Neil Armstrong b) Buzz Aldrin c) Yuri Gagarin d) Alan Shepard Review: 9. Who was the first person to set foot on the moon? a) Neil Armstrong b) Buzz Aldrin c) Yuri Gagarin d) Alan Shepard 66
Review: 9. During what time is the most direct sunlight furthest north of the equator? a) Vernal Equinox b) Autumnal Equinox c) Summer Solstice d) Winter Solstice Review: 9. During what time is the most direct sunlight furthest north of the equator? a) Vernal Equinox b) Autumnal Equinox c) Summer Solstice d) Winter Solstice 67
Review: 10. Approximately how long does it take for the moon to make one complete orbit around the earth? a) 1 day b) 1 week c) 1 month d) 1 year Review: 10. Approximately how long does it take for the moon to make one complete orbit around the earth? a) 1 day b) 1 week c) 1 month d) 1 year 68
The Sun-Earth-Moon System For the Test: What you need to know: Types of electromagnetic radiation Types of telescopes Surface features of the moon Theory of the formation of the moon Motion of the earth and moon around the sun. Solstices, equinoxes, and eclipses Phases of the moon 69
Bell-Ringer: Come up with a test question that I will use on the Test tomorrow. Write it as a true/false or multiple choice style question Must be over a topic from Chapter 27 Types of Telescopes 70
Types of Telescopes Types of Telescopes 71
Types of Telescopes Space-Based Astronomy 72
Space-Based Astronomy What benefit do robotic probes have over human exploration? The Lunar Surface B Highlands A Maria 73
The Lunar Surface C Impact Crater The Lunar Surface D Rays 74
The Lunar Surface E Rilles The Lunar Surface Regolith 75
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