Chapter 30 Section 1 Chapter 30 Section 1 HandoutHandout
Characteristics of StarsCharacteristics of Stars
11
What is a star?What is a star? A ball of gases that gives off a tremendous A ball of gases that gives off a tremendous
amount of electromagnetic energy.amount of electromagnetic energy.
22
How does the color of stars seen from How does the color of stars seen from Earth differ from their actual color?Earth differ from their actual color? From Earth, stars appear as tiny specs of From Earth, stars appear as tiny specs of
white light, but they actually vary in color.white light, but they actually vary in color.
33
How do astronomers learn about stars?How do astronomers learn about stars? By analyzing the light that stars emit.By analyzing the light that stars emit.
44
What are spectrographs?What are spectrographs? Devices that separate light into different Devices that separate light into different
colors.colors.
55
What are the three types of spectra?What are the three types of spectra? EmissionEmission AbsorptionAbsorption ContinuousContinuous
66
What does a star’s dark-line spectrum What does a star’s dark-line spectrum reveal?reveal? The star’s composition and temperature.The star’s composition and temperature.
77
What is true of the layers of a star?What is true of the layers of a star? The inner layers are very hotThe inner layers are very hot The outer layers are somewhat coolerThe outer layers are somewhat cooler
88
Elements in the outer layers of a star Elements in the outer layers of a star absorb:absorb: Some of the light radiating from within the Some of the light radiating from within the
star.star.
99
What do the colors and lines in the What do the colors and lines in the spectrum of a star indicate?spectrum of a star indicate? The elements that make up the star.The elements that make up the star.
1010
What is the most common element in What is the most common element in stars?stars? Hydrogen (H)Hydrogen (H) Helium (He)Helium (He)
1111
Matching star color with star temperature.Matching star color with star temperature. Less than 3,500Less than 3,500ooCC
RedRed
1212
Matching star color with star temperature.Matching star color with star temperature. 10,000-30,00010,000-30,000ooCC
Blue-whiteBlue-white
1313
Matching star color with star temperature.Matching star color with star temperature. 3,500-50003,500-5000ooCC
OrangeOrange
1414
Matching star color with star temperature.Matching star color with star temperature. 5,000-6,0005,000-6,000ooCC
YellowYellow
1515
Matching star color with star temperature.Matching star color with star temperature. 7,500-10,0007,500-10,000
WhiteWhite
1616
What is indicated by a star’s color?What is indicated by a star’s color? The surface temperature of the star.The surface temperature of the star.
1717
What color are the coolest stars?What color are the coolest stars? RedRed
1818
What is the diameter of the sun?What is the diameter of the sun? 1,390,000 km1,390,000 km
1919
Stars that are very dense may have:Stars that are very dense may have: More mass than the sun and still be much More mass than the sun and still be much
smaller than the sun.smaller than the sun.
2020
What two kinds of motion are associated What two kinds of motion are associated with stars?with stars? Actual motion and apparent motion.Actual motion and apparent motion.
2121
What causes the apparent motion of the What causes the apparent motion of the stars, which we can see with the unaided stars, which we can see with the unaided eye?eye? The movement of the Earth.The movement of the Earth.
2222
What causes the circular trails of light What causes the circular trails of light seen in long-exposure photographs of the seen in long-exposure photographs of the stars?stars? The rotation of Earth on its axis.The rotation of Earth on its axis.
2323
In the Northern Hemisphere, the In the Northern Hemisphere, the movement of stars called circumpolar movement of stars called circumpolar stars makes them appear:stars makes them appear: To circle Polaris, the North Star.To circle Polaris, the North Star.
2424
What is true of all visible stars at the North What is true of all visible stars at the North pole?pole? They are circumpolar.They are circumpolar.
2525
What are three types of actual motion that What are three types of actual motion that stars may have?stars may have? They rotate on an axisThey rotate on an axis They may revolve around another starThey may revolve around another star They either move away from or toward out They either move away from or toward out
solar system.solar system.
2626
What is the Doppler effect?What is the Doppler effect? The apparent shift in wavelength of light The apparent shift in wavelength of light
emitted by a light source moving toward or emitted by a light source moving toward or away from an observer.away from an observer.
2727
What does the fact that most distant What does the fact that most distant galaxies have red-shifted spectra indicate?galaxies have red-shifted spectra indicate? That those galaxies are moving away from That those galaxies are moving away from
Earth.Earth.
2828
What is a light-year?What is a light-year? The distance that light travels in one year.The distance that light travels in one year.
2929
How many kilometers does light travel in How many kilometers does light travel in one year?one year? 700 trillion km700 trillion km 700,000,000,000,000 km700,000,000,000,000 km
3030
When we witness an event on the sun, When we witness an event on the sun, when did it actually take place?when did it actually take place? About 8 minutes before we see it.About 8 minutes before we see it.
3131
Except for the sun, what star is nearest to Except for the sun, what star is nearest to Earth?Earth? Proxima CentauriProxima Centauri
3232
What is parallax and how do scientists use What is parallax and how do scientists use it?it? The apparent shift in a star’s position when The apparent shift in a star’s position when
viewed from different locations.viewed from different locations. Scientists measure it to determine a relatively Scientists measure it to determine a relatively
close star’s distance from Earth.close star’s distance from Earth.
Top Related