06-04_task (1)

pdf

School

University of Texas *

*We aren’t endorsed by this school

Course

2302

Subject

Astronomy

Date

Dec 6, 2023

Type

pdf

Pages

6

Uploaded by MegaThunderBadger24

Report
Earth and Space Science © ACCESS Virtual Learning 2022 Name: Evan Swai Date: School: Facilitator: 6.04 Spectral Signature Lab (59 Points) Use your lesson and the linked resources to answer the questions below. 1. What is the difference between a continuous spectrum, a bright line spectrum, and an absorption spectrum? Write your response below: Continuous spectrum is a spectrum of light that has all the colors of the rainbow without any interruption. A bright line spectrum is a spectrum consisting of bright lines on a dark background. An absorption spectrum is a spectrum with dark lines on a continuous background. The dark lines represent the absorption of specific wavelengths of light by the atoms in the gas. 2. Compare the unknown sample to those of elements A, B, C, D. Which elements are found in the star and explain how you know by describing the color that the line(s) would be. Assume that the right side of the diagram is at 700 nm or the red end of the spectrum. "To Identify an Unknown Element" by Tony Mangiacapre Write your response below: To compare the unknown sample with elements A, B, C, and D, we need to look for the lines in the unknown sample that match the lines in the known elements. By comparing
Earth and Space Science © ACCESS Virtual Learning 2022 the lines, we can determine which elements are present in the unknown sample. The color of the lines in the spectrum depends on the element being observed. 3. Launch the interactive. Select Astronomical Uses at the bottom. Select Radio . What types of information are collected from radio waves and what is the temperature of these objects? Write your response below: Radio waves are used to collect information about the temperature and composition of astronomical objects. Radio waves can penetrate dust clouds that visible light cannot, allowing astronomers to study the interiors of these objects. 4. Close the info window for Radio Waves and select Microwave . What types of information are collected from microwaves and what is the temperature of these objects? Write your response below: Microwaves are also used to study astronomical objects. They can provide information on the temperature and composition of the objects. They are also used to study the cosmic microwave background radiation, which is the remnant radiation from the Big Bang. 5. Close the info window for Microwave and select Visible . What types of information are collected from visible light and what is the temperature of these objects? Write your response below: Visible light is used to study the properties of astronomical objects. By analyzing the spectrum of visible light, we can determine the temperature, composition, and motion of the object. 6. Close the info window for Visible and select X-rays . What types of information are collected from X-rays and what is the temperature of these objects?
Earth and Space Science © ACCESS Virtual Learning 2022 Write your response below: X-rays are used to study high-energy astronomical objects such as black holes and supernovae. X-rays can provide information on the temperature and composition of these objects. 7. Go to Spectra of Gas Discharges (link located on task page). Scroll to the table at the bottom. Which element has the greatest number of emission lines? Hydrogen has the greatest number of emission lines, while helium has the fewest. The spectral lines of hydrogen and helium are the same in that they are both found in the visible part of the spectrum. However, the lines for hydrogen are much more numerous and closer together than the lines for helium. 8. Which element has the fewest number of emission lines? The spectral lines of oxygen and carbon are the same in that they are both found in the visible part of the spectrum. However, the lines for oxygen are more numerous and closer together than the lines for carbon. 9. Scroll to the top and look at the emission lines of hydrogen and helium. What is one way that the spectral lines are the same and two ways that the spectra are different? Write your response below: Three differences between the Naked-Eye View and the Telescope View are magnification, resolution, and sensitivity. The Telescope View provides a more detailed and clearer image of the spectrum. 10. Look at the emission lines of oxygen and carbon. What is one way that the spectral lines are the same and two ways that the spectra are different? Write your response below: The Spectrum at Analyzing Light: Spectrum of the Star Altair is an absorption spectrum. The part of the spectrum that has more lines is the blue end of the spectrum, while the part with thicker/darker lines is the red end.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
  • Access to all documents
  • Unlimited textbook solutions
  • 24/7 expert homework help
Earth and Space Science © ACCESS Virtual Learning 2022 11. Go to Analyzing Light: Spectrum of the Star Altair (link located on task page). What are three differences you notice between the Naked-Eye View and the Telescope View ? Write your response below: 12. Look at the Spectrum at Analyzing Light: Spectrum of the Star Altair (link located on task page). Is this an emission or an absorption spectrum? The Spectrum at Analyzing Light: Spectrum of the Star Altair is an absorption spectrum. 13. Look at the spectral lines in the Spectrum view at Analyzing Light: Spectrum of the Star Altair (link located on task page). Which part of the spectrum has more lines? Which part of the spectrum has thicker/darker lines? Write your response below: The part of the spectrum that has more lines is the blue end of the spectrum, while the part with thicker/darker lines is the red end. 14. Look at the Interpretation at Analyzing Light: Spectrum of the Star Altair (link located on task page). What does the spectrum tell us about the temperature, composition, and motion of the star? Write your response below: The spectrum tells us that the star is composed of hydrogen and helium with small amounts of other elements. The temperature of the star is around 8,500 Kelvin, and the star is moving away from Earth at a speed of 12 km/s. 15. What is the evidence from the spectrum that this star is hot? The evidence from the spectrum that this star is hot is that the spectrum shows a high intensity of light in the blue and ultraviolet regions of the spectrum.
Earth and Space Science © ACCESS Virtual Learning 2022 16. Go to PhET: Blackbody Spectrum (link located on task page). Click the Play button to start the simulation. Turn on Graph Values and Labels . The Spectral Power Density is on the Y axis. This is the intensity of the light. The Wavelength is on the X axis. This is measured in micrometers. There are 0.001 micrometers in 1 nanometer. What do the + and - on each axis do? Write your response below: The + and - signs on each axis allow you to zoom in or out on the graph by adjusting the range of values displayed. 17. Complete the table below by moving the slider (on the thermometer to the right) to each object. λmax means the peak of the graph. Note: You may need to toggle the X and Y axis zoom to see information for Sirius A. Lightbulb Sun Sirius A Temperature 2700k 5778k 9940k Peak wavelength (λmax) 0.8 0.5 0.3 Visible Color red yellow blue Spectral Power density of (λmax) 2.1 x 10^-9 1.0 x 10^-8 1.4 x 10^-8 Electromagnetic Spectrum (λmax) infared visible Ultraviolet 18. As the temperature increases, what happens to the color of the object? As the temperature increases, the color of the object shifts from red to yellow to white to blue. 19. As the temperature increases, what happens to the peak wavelength? As the temperature increases, the peak wavelength decreases. 20. As temperature increases, what happens to the spectral power? As temperature increases, the spectral power increases. 21. As the wavelength decreases, what happens to the Spectral Power Density? As the wavelength decreases, the Spectral Power Density increases. 22. Based on what you have learned, what can you conclude about wave frequency, wavelength, and spectral power density?
Earth and Space Science © ACCESS Virtual Learning 2022 Write your response below: As the frequency of a wave increases, its wavelength decreases, and its spectral power density increases. 23. Why does it make sense that Sirius is a blue star? Write your response below: It makes sense that Sirius is a blue star because its spectrum shows a peak in the blue/violet part of the spectrum, indicating that it emits a lot of blue and violet light. Additionally, its high temperature of around 9940 K also contributes to the blue color.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
  • Access to all documents
  • Unlimited textbook solutions
  • 24/7 expert homework help