Setup for Spherical Astronomy Problem

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SUMMARY

The discussion centers on the setup for understanding the visibility of the south celestial pole (P) from a northern latitude observing site. The participant queries why P appears above the horizon when the latitude of the observing site is positive, specifically referencing the Bosscha Observatory located at 6º 49' 00″.0 S. The confusion arises from the relationship between the observer's latitude and the positioning of celestial objects, particularly the moon (M) and the zenith (Z). The participant ultimately resolves their misunderstanding with clarification from another forum member.

PREREQUISITES
  • Understanding of celestial coordinates and their relation to latitude
  • Familiarity with the concepts of zenith and celestial poles
  • Knowledge of the equatorial coordinate system
  • Basic principles of spherical astronomy
NEXT STEPS
  • Research the celestial coordinate system and its application in astronomy
  • Study the visibility of celestial objects based on observer latitude
  • Explore the concept of declination and its impact on celestial navigation
  • Learn about the Bosscha Observatory and its significance in astronomical studies
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Astronomy students, educators, and amateur astronomers seeking to understand celestial mechanics and the visibility of celestial objects based on geographic location.

Kelli Van Brunt
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Homework Statement
A full moon occurred on June 19, 2008 at 00h 30m West Indonesian Time (local civil time for western part of Indonesia with reference to geographic longitude of 105° E). Calculate the extreme values of duration of the Moon above the horizon for observers at Bosscha Observatory (longitude: 107º 35' 00″.0 E, latitude: 6º 49' 00″.0 S, Elevation: 1300.0 m). Time zone = UT +7h 00m.
Relevant Equations
None; this is a conceptual question
My apologies for not detailing my attempts at a solution; I'm not sure how to to digitally illustrate or describe the various setups I attempted before looking at the solution to this problem. I am also ONLY asking about the setup, though I included the full question for context.
The solution to this problem has the following setup:
QdDFwYBsCbuvMd7hdNkj_j9_Nu4roFXWSE6Sgcd_filFjsOrkw.png


Where Z = zenith, P = south celestial pole, and M = moon (I assume represented by the path of the little blue spheres). SP is the latitude of the observing site and PM is 90º - declination of Moon. My main question is, why is P above the horizon/NESW plane when the latitude of the observing site is positive? Shouldn't an observer in the north not be able to "see" the south celestial pole? I drew a diagram of the situation in the equatorial plane below and am wondering why this is not the correct setup. The horizontal analogy to this would, I assume, be the above diagram but with the moon's path, celestial equator, and celestial south pole shifted clockwise so that M is to the right of the zenith and P is below the horizon. I apologize for my very bad graphic design skills. Can anyone clarify this for me?
pixil-frame-0 (3).png

EDIT: Sorry for posting this twice - that was an accident.
 
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Kelli Van Brunt said:
My main question is, why is P above the horizon/NESW plane when the latitude of the observing site is positive? Shouldn't an observer in the north not be able to "see" the south celestial pole?
Bosscha Observatory is south of the equator. Although the latitude was given as an unsigned value, you know that it's south of the equator by the "S" at the end of ... latitude: 6º 49' 00″.0 S.
 
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collinsmark said:
Bosscha Observatory is south of the equator. Although the latitude was given as an unsigned value, you know that it's south of the equator by the "S" at the end of ... latitude: 6º 49' 00″.0 S.
I can't believe I missed that, thank you so much. That cleared up everything.
 
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