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Homework #2
• Question 1:  (1 point) If you were kidnapped and transported to a distant location on Earth, but noticed that Polaris was 20 degrees above the horizon, what could you figure out about your whereabouts?
• *3.* The latitude of my location is 20 degrees north
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• Question 2:  (1 point) If the moon rose at about 7pm one night (and you know now that its phase would be full or close to full, right?), at about what time will the moon rise the next night?
• *3.* 7: 45 PM   (Note this can vary because of the moon’s elliptical orbit).
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• Question 3:  (1 point) Imagine that you're kidnapped by aliens and transported to a distant world in a different solar system. They will release you if you show your understanding of orbital dynamics. There is a planet with a period (year) 8 times longer than the planet you are on. How much further away is it from the local sun?
• *2.* 4 times as far.  
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• Question 4:  (1 point) What is the circular velocity of Mercury?
• *3.* About 50 km/s.
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• Question 5:  (1 point) What is the correct order that shows increasing photon energy for wavebands of the electro-magnetic spectrum?
– *1.* Radio -- Infrared -- Optical -- Ultraviolet -- X-ray -- Gamma Ray  
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• Question 6:  (1 point) The textbook talks about the resolving power of optical telescopes on page 75, but resolving power also depends on the wavelength of light being collected. The resolving power is proportional to the ratio of the wavelength to the telescope diameter (wavelength/Diameter). Which telescope has the best theoretical resolution?
• * 4.* The 10-meter Keck telescope operating in the optical at 500 nanometers.  
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