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What is the definition of a solar system?The sun and its planets, asteroids, comets, and so on.

What is the definition of a planet?A non-luminous body in orbit around a star, large enough to be spherical and to have cleared its orbital zone of other objects.

What is a galaxy? What is the name of our galaxy?A large system of stars, stars clusters, gas, dust, and nebulae orbiting a common center of mass. Milky Way Galaxy.

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What is the name of our super cluster?The Virgo Super Cluster

What comes first and what comes last in our astronomical address?Earth and the Universe

What is an AU?An astronomical unit is the average distance from the earth to the sun.

Outside of Book:How many miles across is the earth?8,000 miles

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* (a) Polaris(Zenith) is the star indicating the pole; stars move in a counter- clockwise motion (to the west, or right)

* (b) Nadir(Zenith) indicates the celestial equator; stars rise in the east* (c) Mid-latitude stars rise in the east, set on the west

7. Do people from other cultures on Earth see the same stars, constellations, and asterisms that you se

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Cycles of the moon include which three points?The same side of the moon always keeps facing the Earth.The seemingly changing shape of the moon (as it passes through its cycle of phases) is produced by sunlight illumination different parts of the side of the moon.The orbital period of the moon around the Earth is not the same as the length of a moon phase cycle.

What causes the seasons and why is it cold in the winter and hot in the summer? Include the terms “solstice” and “equinox” in your answer.

*due to the tilt of the earth; 1) longer days 2) Steeper angle of sunlight

*solstice = sun is stationary*equinox = equal day and night

Why can you never see a full moon overhead at sunset?

*Because the moon is behind the sun in order for it to be full

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Describe the relative positions of the earth, sun, and moon in space during

a) a total eclipse of the sun: solar eclipse- new moon passes between the sun and earth

b) a total eclipse of the moon: lunar eclipse-full moon passes through earth’s shadow

According space.com,

A total lunar eclipse can only occur at Full Moon, when Earth blocks the sunlight normally reflected by the Moon. Some sunlight is bent through Earth’s atmosphere, typically allowing the Moon a coppery glow.

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Tides depend on several factors, including where the sun and moon are relative to the Earth.

For example, when the moon and sun align with the Earth, tides are stronger because the attraction of the moon and the sun combine. When they form a right angle with the Earth, their pulls partially cancel each other out, so the tides are weaker. The moon's gravitational attraction has more effect on tides than the sun's because it is 390 times closer to the Earth. Thus, its pull is twice as strong as the sun's [source: NOAA: Tides and Water Levels].

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Who created a way to measure the brightness of stars and what is that system called?

Hipparchus and the magnitude scale.

If a star has an apparent visual magnitude of 1, then is it brighter or more faint than a star with a magnitude of 6?

The larger the magnitude number, the fainter the star. Think first-class stars are brighter and sixth-class stars.

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From the Earth as a vantage point, the picture shows how, the planet further from the sun seems like it is moving in a backwards loop.

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explains retrograde motion through epicycles in which planets move in loops backwards to forwards around a larger circle called a deferent. The deferent was

centered around a point halfway between the Earth and another point called the equant.

Copernicus thought that the planets orbited the Sun, and that the Moon orbited Earth. Since the Sun was the center of the universe, it did not move, nor did the stars.

*explains retrograde motion by planets passing each other. The planets with smaller orbits, or closer to the Sun, move faster, so they overlap the outer and larger planets; eventually the planets catch up to each other.

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Epicycles are circular orbits within orbits that were used to (incorrectly) describe the orbits of objects in the Ptolemaic system (about A.D. 150). In Ptolemy's model of the solar system, an orbiting planet (or moon) moved in a series of circular orbits (epicycles) and the center of these epicycles orbited in another circular orbit (called the deferent) that was a circle offset from the Earth. Many layers of epicycles were needed to approximate real (elliptical) orbits with their retrograde motion.

http://www.enchantedlearning.com/subjects/astronomy/glossary/indexe.shtml

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The orbit of every planet is an ellipse with the Sun at one of the two foci.

A line joining a planet and the Sun sweeps out equal areas during equal intervals of time.

The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.

P^2 = a^3 ( ) where

p= orbital period and a=semi-major axis of the orbit

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Mention several of Galileo’s telescopic observations and explain how they support the heliocentric viewpoint of the solar system.

Earth’s moon is uneven and rough

-(which means it is not perfect)

Moons of Jupiter orbit so they disappear from day to night

-(which means planets do not orbit around Earth as the center)

the phases of Venus are similar to the moon

-(which means the moon is not special)

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Discuss the relationship of the aperture of a telescope and its

a) light-gathering power- collect light; bigger aperture

b) resolving power- to reveal fine detail with less diffraction; bigger aperture

What determines the magnifying power of a telescope? Give a numerical example of a calculation of magnification.

*aperture of lens

Ex: 8 inches diameter aperture 50x/400x per inch vision

Reflecting telescope: a mirror forms an image by bending light.

What problem led Isaac Newton to invent the reflecting telescope? Also, list some other advantages of reflectors over refracting telescopes./

*no chromatic aberration

*cheaper

*support in bark surface

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1) Refracting telescope: a lens bends light to gather and focus an image; has a primary lens and primary mirror

Chromatic abberation: the distortion of light at different wavelengths so they are scattered slightly and produce a fuzzy image

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*sunspots & their 11 year cycle

*magnetic field

*nuclear fusion

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1) gravity- pulls on the earth

*2) electromagnetic force – pushes

*3) nuclear strong – atomic bomb

*4) nuclear weak – radio activity

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Why is light referred to as electromagnetic radiation?

It is made of electric and magnetic fields; it is a wave which carries energy through space and transfers energy.

What is radiation?

-Anything that spreads outward from a source, such as light radiating from a source.

What is electromagnetic spectrum?

Types of electromagnetic radiation arranged in order of increasing wavelength. Rainbows are spectra of visible light. Red has the longest, violet has the shortest; beyond red is infrared, and then microwave, while shorter than violet is ultraviolet, x-ray, then gamma ray.

What is a particle of light?

A photon

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Describe what the continuous, emission, and absorption spectra look like, and discuss the circumstances under which each is formed.

Circumstances:

*hot, greater pressure

*emits light at specific wavelengths

*radio passes thru cool gas; each atom absorbs its own color

How can you estimate the temperature of a star with your unaided eye? How does this work?

*if it is bluer, it is hotter; while redder, it is cooler

*it’s based on photons emitted by an excited atom

We may consider three principal types of spectra which appear when the light from an object is broken up into its component wavelengths or "dispersed":

a continuous spectrum or continuum; the emission of a thermal spectrum is one type of continuum.

an absorption spectrum or sometimes an absorption-line spectrum.

an emission spectrum or emission-line spectrum.

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