Tools of Modern Astronomy:
Read pages 784-790 in the textbook to find the answers to the question below. Use the back of this page or a sheet of binder paper if you need more room for the answers.
1. What did enslaved African Americans follow as they moved north to the Free States?
What are constellations? big dipper; patterns of stars;
2. What are stars? What kind of light do your eyes see? What is light? How does
electromagnetic radiation travel through space? What kind of radiation does a
electric heater give off? Can you see radio waves? huge spheres glowing gas;
visible; form of EM spectrum; in waves; infrared; no;
3. What is wavelength? How big is the wavelength of visible light? What is a
spectrum? What does the electromagnetic spectrum include? Where is visible
light located on the electromagnetic spectrum? What color has the longest
wavelength? What color has the shortest wavelength? wave crest to wave crest;
≤ 1 x 10-6 m; range of different wavelengths (expressed as colors for visible light);
middle; red; blue;
4. Objects in space give off what type of electromagnetic radiation? What type of
telescope did Galileo use? How does a refracting telescope work? What is a
convex lens? What is focal length? What is a reflecting telescope? Who first used a
reflecting telescope? What are most visible light telescopes today? all types;
refracting; convex lens; thick middle; point where light is focused from objective
lens; mirror in place of objective lens; Newton; reflecting
5. What are radio telescopes? How big can they be in diameter? Are they like refracting
or reflecting telescopes? Are radio waves coming from space strong or weak? Where
is the reflected radio waves collected? What kinds of electromagnetic radiation do
other telescopes collect? What is an observatory? Why have astronomers built
light telescopes on top of mountains? Where is the best observatory on Earth? When
do astronomers who look through light telescopes work? When can radio
astronomers work? detect radio waves; 300 m; reflecting; weak; antennas; infrared,
UV, x-ray, gamma; contained telescope; better seeing (atmosphere distortion & city
lights disrupt seeing); Mauna Kea, Hawaii; night; anytime
6. What type of telescopes are placed on satellites? Why? Where is the Hubble Space
Telescope? How big is its mirror? How many more times can the Hubble see detail
than the best visible light telescopes on Earth? What other types of radiation can the
Hubble see? UV, x-ray, gamma; atmosphere blocks; Hubble orbits Earth; 2.4 m; 7 x;
visible, UV, infrared
7. What does a spectrograph do? What two types of data can astronomers get from
spectrographs? What do chemical elements in the atmosphere of a star do to radiation
streaming from star? How do astromomers identify different elements on a spectrum
of starlight? splits light into colors; chemical compositions & temps from stars;
absorb light; dark absorbtion lines;
8. What is the chemical composition of most stars (including the Sun)? What effects the
amount of energy each element absorbs? How do astronomers determine the
temperatures of stars? At what temperature does hydrogen produce strong spectral
lines? H, He; temp; compare line spectras at different temps; 10,000 ° C