1) Astronomers have used the idea of a celestial sphere as a model for the night sky. Please give a brief description of the following parts of the celestial sphere.
a. Celestial Equator
b. Celestial Pole
c. Ecliptic
d. Northern Celestial Hemisphere
2) Where can we find Venus in the night sky? How will its appearance change by the end of this semester?
3) Which three of the brightest five planets can be seen in the morning sky? Which planet of these three will experience the greatest change in appearance as we head toward the summer?
4) What is the phase of the moon as we begin this week and what will it be when the weekends? When is the best time to look for the moon this week?
5) We will soon experience the vernal equinox in the northern hemisphere, (the autumnal equinox in the southern hemisphere). Explain the position of the Sun using some of the terms in question 1.
6) The moon orbits the Earth every 23.7 days, yet the lunar cycle is 29.5 days. Please explain the discrepancy between these two periods.
7) Sirius has an approximate visual magnitude of -1.46 (Sirius A)
a. How much brighter is Sirius than the star Achernar (Mv = 0.46) ? (intensity, not magnitude)
b. Sirius has a small white dwarf companion (Sirius B) with a magnitude of 8.5. How much brighter is the main star (Sirius A) than its companion (Sirius B)?
8) Give two reasons (related to the sky conditions) why building an astronomical observatory in the NYC metropolitan area would be a bad idea.
9) When was the last total solar eclipse and the last total lunar eclipse visible from North America and when will the next one take place?
10) Describe two advantages of a reflector telescope over a refractor telescope.
11) What type of object gives off a blackbody spectrum and what type of object gives off an emission or absorption spectrum?
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