Phys 102 Astronomy OBSERVING THE SKY BAYER DESIGNATION

Transcription

1 Phys 102 Astronomy Name Key OBSERVING THE SKY 1) 8 Complete the table. 2) 2 Which star is brightest in our sky? α CMa, Sirius 3) 2 Which star would be brightest if they were all at the same distance? β Ori, Rigel 4) 2 Which stars is farthest from us? β Ori, Rigel BAYER DESIGNATION 5) 10 Label the diagram with star names,constellation lines, and the Winter Hexagon using Appendix 2, pp , and the Atlas Charts in the Field Guide. Extra Credit: Name this object Saturn RA VISUAL MAG. (V) ABSOLUTE MAG. (M V ) DISTANCE (ly) OTHER NAME α CMa 6 h 45 m Sirius α CMi 7 h 39 m Procyon α Gem A 7 h 35 m Castor β Gem 7 h 45 m Pollux α Aur 5 h 17 m Capella α Tau 4 h 36 m Aldebaran α Ori 5 h 55 m Betelgeuse β Ori 5 h 15 m Rigel AURIGA Capella Extra Credit: Name this object Mars Castor Pollux GEMINI TAURUS Procyon CANIS MINOR Aldebaran Betelgeuse ORION WINTER HEXAGON Sirius Rigel CANIS MAJOR Extra Credit: Name this line Ecliptic Extra Credit: Name this line Celestial Equator

2 4 min. 12 min West 3 East Diagram adapted from Nicastro, Anthony J., Laboratory Astronomy: Experiments and Exercises, USA: W m C. Brown Publishers, 1990 Page 2

3 6) 20 Using the Analemma, and the equations for the azimuths of rising and setting and the length of the day, A rise = cos 1 sin δ cos λ degrees A = 360 cos sin δ = cos λ set A rise degrees find the rising and setting azimuths and the length of the day for the following stars: STAR OTHER NAME RIGHT DECLINATION CANTON, NY (λ = = 44+(36/60) = 44.6 ) ASCENSION A rise A set t α Ori Betelgeuse 5 h 55 m h β Ori Rigel 5 h 15 m h DATE t = 2 1 cos 15 ( tan λ tan δ ) hours Sol Mar. 3, h 57 m n Sol May 16, h 33 m h Show the approximate rising position of each star below (they all rise at an angle of 45 in Canton) Celestial Equator α Ori β Ori Sol 5/16 Sol 3/3 North (0 ) You are here East (90 ) looking east South (180 ) I M ASTOUNDED BY PEOPLE WHO WANT TO KNOW THE UNIVERSE WHEN IT S HARD ENOUGH TO FIND YOUR WAY AROUND CHINATOWN. -- WOODY ALLEN 7) 6 On the dates given, at what clock time does solar noon occur in Potsdam at longitude 75 W? DATE DECLINATION OF SUN SUN S POSITION AT CLOCK NOON (DEGREES EAST OR WEST) MINUTES BY WHICH SUN IS EARLY OR LATE FOR CLOCK NOON CLOCK TIME OF SOLAR NOON Mar 3, East 12 min. late 12:12 pm May 16, West 4 min. early 11:56 am Page 3

4 8) 6 Reykjavik, Iceland is located at 64 o N 22 o W, yet it is in the same time zone as Greenwich, a suburb of London, England (51 29 N, W). a) 4 When it is solar noon in Reykjavik, what is the civil (clock) time? 22 4 min/degree = 88 minutes = 1 hour, 22 minutes Since Reykjavik is west of Greewich, solar noon occurs late, at 1:22 pm b) 2 Is Reykjavik in the most astronomically "logical" time zone? Explain your answer. Astronomical logic would have clock noon and solar noon occur as close as possible, so Reykjavic sould be one timezone west of Greenwich 9) 15 Complete the following table for the phases of the moon (phases are NOT in order!): PHASE ELONGATION degrees E or W RISING TIME TRANSIT TIME SETTING TIME WAXING GIBBOUS 135 E 3 PM 9 PM 3 AM THIRD QUARTER 90 W 12 AM 6 AM NOON FULL PM MIDNIGHT 6 AM WANING CRESCENT 45 W 3 AM 9 AM 3 PM FIRST QUARTER 90 E NOON 6 PM 12 AM eastern elongations western elongations sun light Page 4

5 10) 21 Use appendix 11 in the Field Guide for July 1, 2006 to complete the following table: Object Planetary Longitude Elongation Atlas Chart # Constellation Sol ( ) Gemini Mercury ( ) E 13 Cancer Venus( ) W 11 Taurus Mars ( ) E 26 Cancer (almost to Leo) Jupiter ( ) E 28 Libra Saturn ( ) E 13 Cancer Luna ( ) E 27 Leo 11) 6 Show where the planets will be in the observer s sky at sunset on the digram below.. j Sun s PL o Observer s meridian Come look for the planets with me! m t y Sun s PL ± E observer looking south Sun setting on western horizon W Sun s PL 100 v Sun s PL - 90 : 10 Page 5

6 12) For the following questions, refer to the Sky Gazer s Almanac. a) 2 When does the Vernal equinox occur (date and time)? 1:26 pm EST on March 20. b) 8 What will be the longest day of the year? When will the earliest sunrise and latest sunset occur? Why do these not all occur on the same day? Longest day: June 21. Earliest sunrise: June 14. Latest sunset: June 27. They don t occur on the same date due to the analemma! c) 2 When will Earth be at aphelion (date and time)? 7 pm EDT on July 3. d) 2 When will Jupiter be at opposition? On May 3, Jupiter is at opposition & transits at midnight. e) 10 List the events that take place before solar midnight on the night of March 19-20, I get 10 events. Time Event 6:11 pm Sunset 6:55 pm Sirius Transits 7:36 pm End of Evening Twilight 7:55 pm Pollux Transits 8:33 pm Saturn Transits 10:06 pm Jupiter Rises 10:17 pm Regulus Transits 11:17 pm Waning Gibbous Moon Rises 12:00 AM Clock Midnight 12:07 am Solar Midnight 13) 6 label the diagrams below with the sun and the moon (in the appropriate phase) for observations of the moon with the given elongations and times a) 90 7 PM PHASE: _ 1_ st Quarter b) AM PHASE: Waning Gibbous Page 6 c) 45 Noon Waxing Crescent PHASE:

7 14) 10 In Night Brought to Numbers in The Soul of the Night, Chet Raymo writes: One day I met a friend in a corridor of my college. We both carried large books: hers an anthology of Elizabethan poetry, mine a volume of the Smithsonian Star Catalog. Oh! Stars! she said. How wonderful! I opened my book. It was full of numbers. The coordinates and specifications of of 96,000 stars, in a book the size of the New York City telephone directory. Right ascensions and declinations, proper motions, radial velocities, spectral types, visual and absolute magnitudes, distances in parsecs. My friend s bright expression faded. Grief brought to numbers cannot be so fierce, she said quoting John Donne. The stars in my Smithsonian Catalog were not the fierce stars my friend hoped to find. They were not the stars the Little Prince gave to his friend the aviator, stars that tinkled like little bells and sang like rusty pulleys. Poets spurn this business of numbering stars. They would prefer the spangled night unquantified. They would prefer to see night s candles burning in a summer sky like tapers in a cathedral. Write a paragraph in response to this essay. Do you agree that poets prefer the sky unquantified? Or do you agree with Emerson that He who knows what sweets and virtues are in the ground, the water, the plants, the heavens and how to come at these enchantments is the rich and royal man? What riches have you gained so far in this course? What in the preceding pages of this exam makes you feel the richest? How can we scientists help the poets to see the riches in the Night Brought to Numbers? Page 7