Rebecca McKenney
Astronomy 101
Mrs. Alburg
25 March 2017
Chapter 2 Review Questions
1. For each of the following wavelength, state whether it is in the radio, microwave, infrared, visible, ultraviolet, X-Ray, or gamma portion of the electromagnetic spectrum and explain your answer. (Page 37 – 38)
Original Number Nanometer (nm) Micrometer (μm) Millimeter (mm) Centimeter (cm) Meter (m) Kilometers (km) Angstrom (Å)
2.6 μm 2,600 2.6 0.0026 0.00026 0.0000026 0.0000000000026 26,000
34 m 34,000,000,000 34,000,000 34,000 3,400 34 0.034 340,000,000,000
0.54 nm 0.54 0.00054 0.00000054 0.000000054 0.00000000054 0.00000000000054 5.4
0.0032 nm 0.0032 0.0000032 0.0000000032 0.00000000032 0.0000000000032 0.0000000000000032 0.032
0.620 μm 0.62 0.62 0.00062 0.000062 0.00000062 0.00000000000062 6200 …show more content…
Why do different elements display different patterns of lines in the spectra? (Pages 44 – 49)
a. Each element can display a different pattern of lines in the spectra because the atoms can absorb “very specific wavelengths from white light.” (Slater)
9. What is the Doppler Effect? Why is it important to astronomers? (Page 49 – 50)
a. The Doppler Effect is the “apparent change in the wavelength of radiation due to the relative motion between the source and the observer along the line of sight.” (Slater)
b. The Doppler Effect is important to astronomers because it gathers “basic information about the motions of planets, stars, and galaxies.” (Slater)
10. If you see a blue star, what does its color tell you about how the star is moving through space? Explain your answer. (Pages 49 – 50)
a. By seeing a blue star, you can predict that a star is moving towards the Earth. As the star comes closer to us, its light waves become shorter between one wave’s crest to another. As the crests become shorter, we tend to start seeing the color blue.
13. Which dimensions of a telescope determines its light-gathering power? (Page 50 – 51)
a. The light-gathering power of a telescope is determined by the size of the objective …show more content…
What is adaptive optics? (Pages 54 – 55) a. The adaptive optics are used on telescopes to help “compensate for the blurring of atmospheric turbulence”. (Slater)
19. What is a charge-couple device (CCD)? Why have CCDs replaced photographic film for recording astronomical images? (Page 57 – 59)
a. A charged-coupled device is “a type of solid-state device designed to detect photons.” (Slater)
b. Photographic film was considered inefficient because only two percent “of light striking” the film had the ability to “trigger the chemical reaction needed to produce an image.” (Slater) With the advance of technology, we can now use the pixels located in the semiconductor wafers of CCDs to create a more efficient finer photograph.
20. Why must astronomers use satellites and Earth-orbiting observatories to study the heavens at X-Ray and gamma-ray wavelengths? (Pages 54 – 57) a. The Earth’s atmosphere prevents a majority of the light that stars produce and is something that, at this point of time, we can’t fix. By using satellites, however, we can go beyond the Earth’s atmosphere.
Source
Slater, Timothy F., and Roger A. Freedman. "Decoding the Hidden Messages in Starlight." Investigating Astronomy: A Conceptual View of the Universe. 2nd ed. New York: W.H. Freeman, 2014. 33-62.
Astronomy 101
Mrs. Alburg
25 March 2017
Chapter 2 Review Questions
1. For each of the following wavelength, state whether it is in the radio, microwave, infrared, visible, ultraviolet, X-Ray, or gamma portion of the electromagnetic spectrum and explain your answer. (Page 37 – 38)
Original Number Nanometer (nm) Micrometer (μm) Millimeter (mm) Centimeter (cm) Meter (m) Kilometers (km) Angstrom (Å)
2.6 μm 2,600 2.6 0.0026 0.00026 0.0000026 0.0000000000026 26,000
34 m 34,000,000,000 34,000,000 34,000 3,400 34 0.034 340,000,000,000
0.54 nm 0.54 0.00054 0.00000054 0.000000054 0.00000000054 0.00000000000054 5.4
0.0032 nm 0.0032 0.0000032 0.0000000032 0.00000000032 0.0000000000032 0.0000000000000032 0.032
0.620 μm 0.62 0.62 0.00062 0.000062 0.00000062 0.00000000000062 6200 …show more content…
Why do different elements display different patterns of lines in the spectra? (Pages 44 – 49)
a. Each element can display a different pattern of lines in the spectra because the atoms can absorb “very specific wavelengths from white light.” (Slater)
9. What is the Doppler Effect? Why is it important to astronomers? (Page 49 – 50)
a. The Doppler Effect is the “apparent change in the wavelength of radiation due to the relative motion between the source and the observer along the line of sight.” (Slater)
b. The Doppler Effect is important to astronomers because it gathers “basic information about the motions of planets, stars, and galaxies.” (Slater)
10. If you see a blue star, what does its color tell you about how the star is moving through space? Explain your answer. (Pages 49 – 50)
a. By seeing a blue star, you can predict that a star is moving towards the Earth. As the star comes closer to us, its light waves become shorter between one wave’s crest to another. As the crests become shorter, we tend to start seeing the color blue.
13. Which dimensions of a telescope determines its light-gathering power? (Page 50 – 51)
a. The light-gathering power of a telescope is determined by the size of the objective …show more content…
What is adaptive optics? (Pages 54 – 55) a. The adaptive optics are used on telescopes to help “compensate for the blurring of atmospheric turbulence”. (Slater)
19. What is a charge-couple device (CCD)? Why have CCDs replaced photographic film for recording astronomical images? (Page 57 – 59)
a. A charged-coupled device is “a type of solid-state device designed to detect photons.” (Slater)
b. Photographic film was considered inefficient because only two percent “of light striking” the film had the ability to “trigger the chemical reaction needed to produce an image.” (Slater) With the advance of technology, we can now use the pixels located in the semiconductor wafers of CCDs to create a more efficient finer photograph.
20. Why must astronomers use satellites and Earth-orbiting observatories to study the heavens at X-Ray and gamma-ray wavelengths? (Pages 54 – 57) a. The Earth’s atmosphere prevents a majority of the light that stars produce and is something that, at this point of time, we can’t fix. By using satellites, however, we can go beyond the Earth’s atmosphere.
Source
Slater, Timothy F., and Roger A. Freedman. "Decoding the Hidden Messages in Starlight." Investigating Astronomy: A Conceptual View of the Universe. 2nd ed. New York: W.H. Freeman, 2014. 33-62.