Earth & Space
1. What does Hubble’s law predict about the speed of a galaxy far away from the Milky Way compared to one that is closer?
2. In a few sentences, describe Hubble’s two major finding about nebulae and explain how they led to the development of the Big Bang theory.
3. List two ways that the measured characteristics of cosmic background radiation provide strong evidence in support of the Big Bang theory and explain how each one is used in support
4. In a few sentences, describe the blackbody problem and how Planck’s theory of the nature of light helped to resolve it.
5. Briefly describe two things that can be learned from examining the emissions or absorption spectra of stars.
6. The following is the absorption spectrum for a star in the 400 to 700 nm range:
7. In a sentence or two, describe how the energy and frequency of a quantum of radiation are related.
8. The frequency of a blue light is 6.5 x 1014Hz. Find the energy contained in one quantum (photon) of this light.
9. Briefly explain why it takes a large force of gravity to trigger nuclear fusion of hydrogen into helium in a protostar.
10. Briefly explain how the nuclear fusion of hydrogen to helium produces energy. Be sure to include E = mc2 in your response.
11. Two stars, A and B, are within the main sequence on the Hertzsprung-Russell diagram. Star A is bigger then star B. The temperature of star A is 4500 K and for star B it is 9000K
a) State which star should be more luminous and explain why.
b) Which star will probably have the shorter lifespan? Explain.
12. Describe the luminosity and temperature of red paint stars compared with stars in the main sequence.
13. A main sequence star, with a mass of 20 Msun, is in its middle age.
a) Describe what happens to the pattern of fusion reactions at its core as it ages and dies.
b) Describe what happens when it runs out of hydrogen fuel.
14. An amateur astronomer, using her backyard telescope and an online database, collected the following data for her location, date, and time:
a) Which object is the highest in the sky?
b) Which object(s) is (Are) not visible?
c) Rank the visible objets in order from brightest to dimmest.
15. a) Sort the following distances into a list from shortest to longest:
1 AU
1 LY
1 pc
1km
b) Which of the four units (AU, LY, km, pc) would be most convenient to measure the distance from you to the following?
i) The moon
ii) The centre of the Milky Way
iii) Jupiter
16. An astronomer measures the angle to a star relative to the Big Dipper constellation at two times in the year, exactly si months apart. In each case the angle is 65degrees.
a) What is the baseline length in AU?
b) What is the distance to the star in AU?
17. Describe two possible reasons for a galaxy to have an irregular shape.
