Topic/Objective:______ / Full Name: ______
Class: ______Period: _____
Date: ______ / TutorUse Only:
Essential Question:
Chapter 28 Stars and Galaxies
28.1 Closer look at Light
  • Light is a form of ______, which is energy that travels in waves.
  • Waves of energy travel at 300,000 km/sec (speed of light
  • Ex: radio waves and x-rays
  • Electromagnetic waves do not need a ______to travel, they travel through ______
  • Electromagnetic waves emitted by an object indicated what ______are present and its motion
  • Electromagnetic radiation waves are arranged into a continuum call the ______.
  • Wide range of wavelengths
  • ______wavelengths with ______frequencies at one end, ______wavelengths with ______frequencies at the other end
  • ______ measured crest to crest/trough to trough
  • ______ the number of that crests of the same wavelength that pass a point in one second.
  • Scientists study the visible light portion of the electromagnetic spectrum.
  • ______of stars allow for astronomers to learn about the star’s elements and motion.
  • Spectra studied using a ______

Summary:
Essential Question:
  • Three types of visible spectra
  • ______spectrum: unbroken band of colors, emitting all colors of visible light
  • glowing solids, such as a light bulb filament
  • glowing liquids, molten iron
  • hot, compressed gases inside a star
  • ______spectrum: unevenly spaced lines of different colors, emitting light of only some wavelengths
  • glowing thin gases
  • every element has its own unique emission spectrum, element’s finger print
  • ______spectrum: dark lines that cross a continuous spectrum.
  • forms when light from a glowing object pass through a cooler gas which absorbs some wavelengths
  • can determine what is present in the cooler gas by comparing emission and absorption spectrum
  • ______Effect is the apparent change in the wavelength of radiation or sound due to relative motion between the object and the receiver.
  • Doppler effect applies to ______as well as sound.
  • Shift of the ______spectra can indicate if the object is moving towards or away from Earth
  • Shift towards the red end of the visible light spectrum, object moving away Earth – ______

Summary:
Essential Question:
  • Shift towards the blue end of the visible light spectrum, object moving towards Earth - ______
  • Doppler effect determined that the universe is ______
Telescopes
  • ______Telescopes – gather far more light than an unaided eye and magnify imagers
  • ______
  • Uses one lens at back to gather and focus light
  • Image reflected on to a small mirror and then the eye piece
  • ______
  • Uses two lenses
  • Lens at the front gathers light
  • Eyepiece magnifies image
  • ______Telescopes
  • Technical term for really big satellite dishes
  • Use to detect energy waves at frequencies lower than visible light
  • Other
  • Detects energy waves at frequencies higher than visible light
  • Usually satellites in space
  • Gamma ray
  • Background radiation
  • X-ray
  • Hubble (infrared)
28.2 Stars and Their Characteristics
  • Observation of stars has been going on for over ______years
  • The grouping of stars are called ______
  • Constellations
  • ______grouping of stars
  • only appear together as viewed from ______from a different angle they do not look like the constellation
  • Grouped together due to ______like they all have the same brightness (______magnitude)

Summary:
Essential Question:
  • Constellations will change shape over ______of years due to the universe expanding
  • Some constellations have been around for thousands of years other were recently conceived
  • Move across the sky from ______to ______(though Earth rotates west to east)
  • Big Dipper and Little Dipper two of the best know constellations point to the ______
  • North Star
  • Current north star is called ______
  • Sits directly over the ______pole
  • Does not ______to the naked eye
  • Very powerful tool for ______
  • Due to ______, Polaris will not always be the “North Star”
  • Circumpolar Constellations – constellations around the north star
  • Create star trails evidence for Earth’s ______
  • North star appears ______in the sky as Earth rotates
  • star trails from circumpolar constellations rotate ______around the north star
  • Circumpolar constellations seem to ______set from some northern hemisphere latitude
  • Distances to stars and other objects in space
  • Unit of measurements on Earth are ______sufficient for space measurements
  • ______ (AU) is used for the distance from Earth to the Sun (150 million kilometers)
  • ______ is the distance light travels in one year (9.5 trillion kilometers)
  • It is a ______measurement
  • Example - 4.2 light-years means that the light we see has been traveling for 4.2 years before we can see it (4.2 X 9.5 trillion km)
  • ______change in an object’s direction due to a change in the observer’s position
  • Parsec short for “parallax second” equal to 3.258 light-years.

Summary:
Essential Question:

  • Stars
  • Elements
  • ______~69%
  • ______~29%
  • Heavier elements ~2%
  • No two stars have the same proportions of elements
  • light that radiates is dependent on composition and temperature, this differs in every star
  • Star spectrum is its fingerprint
  • Mass, Size and Temperature
  • Stars vary greatly in ______, ______, and ______
  • Cannot observe directly so we are estimating what the mass might be
  • ______effect on bodies around the star help with estimating its mass
  • Star ______is expressed as multiples of the mass of our Sun (which has a stellar mass of 1)
  • ______varies more than mass
  • Smallest stars are ______than Earth
  • Largest have diameters more than ______times that of our Sun

Summary:
Essential Question:
  • Stars differ even more in ______
  • Betelguese is about one ten-millionth of our Sun
  • One star is so dense that one ______would weight more than a ______on Earth
  • ______of stars vary
  • Stars have ______colors which indicate different temperatures
  • Cool stars are ______in color
  • Mid-temp are ______in color
  • Hot stars are ______in color
  • Astronomers group stars by ______and color into spectral classes.
  • Star Brightness
  • Actual brightness of a star is ______
  • Dependent on ______and ______
  • ______from Earth is not a factor
  • If two stars are the same size the ______star would be more luminous
  • ______magnitude is how bright a star appears to an observe on Earth
  • Does not factor in ______
  • ______magnitude is the measure of how bright a star would be is all stars were the same distance from Earth (10 parsec)
28.3 Life Cycle of Stars
See foldable for Star life cycle and HR Diagram
Summary:
Essential Question:
28.4 Galaxies and the Universe
Galaxies:
  • The ______ is everything that exists.
  • The ______is everything we can observe.
  • Astronomers have are not sure how old the universe is since the light from the beginning has not yet reach us. The estimate is between 10-20 billion years
  • Galaxies are hard to separate from stars without ______.
  • Hazy patches of light which when viewed through a telescope reveals thousands to billions of stars.
  • Astronomers estimate there are 50- 100 billion galaxies in the observable universe.
  • No two galaxies are the ______, however, they are classified based on ______.
  • There are ______classifications
  • ______(ex. Milky Way)
  • ______are near spherical to lens-shape
  • ______(ex. The two Magellanic Clouds )
Origin of the Universe
  • ______ – explains history of the universe from a tiny fraction of a second after it came into being up to the present
  • ______explanation for how the universe came to being
  • Developed due to ______of stars, galaxies and other objects with telescopes and experimenting with matter on Earth
  • Approximately 10-20 billion years ago all matter in the universe existed in an incredibly hot and dense state, from which it expanded and cooled slowly condensing into stars and galaxies.
  • It is ______at a very slow rate and is still expanding today

Summary:
Essential Question:
  • ______for the Big Bang Model:
  • The universes apparent ______, distance between galaxies and groups of galaxies seems to be increasing with time.
  • Edwin Hubble’s discovery of the ______in the spectra of galaxies supports the expansion of the universe
  • Discovery of radiation called ______background radiation apparently left over from the universe’s beginning.
  • Continues to be tested and examined to seek further evidence to support it
  • Some astronomers are considering alternative ways the universe has reached its present state.
  • It is ______to know for certain how the universe began
  • as long as the Big Bang Model ______crucial tests, it remains the best ______for the origin of the universe
  • If it were to ever fail a test, then astronomers will have to look for a new theory/model

Summary: