Circumpolar star declination problem

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To determine the minimum declination for a star to be considered circumpolar from Damavand Mountain, one must consider the observer's latitude and altitude. The general rule states that the latitude must be greater than the star's declination, but altitude influences visibility, allowing the observer to see stars below the horizon. The altitude of 5.6 km enables the observer to view stars that would typically be obscured at sea level. A diagram illustrating the angle below horizontal from the mountain to the horizon can aid in deriving the necessary declination mathematically. Understanding these factors is crucial for solving the circumpolar star declination problem.
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The Damavand Mountain is located at the North part of Iran, in south coast of
Caspian Sea. Consider an observer standing on the Damavand mountaintop (latitude =
35° 57′ N; longitude = 52° 6' E; altitude 5.6 x10^3m
from the mean sea level) and looking at
the sky over the Caspian Sea. What is the minimum declination for a star, to be seen
marginally circumpolar for this observer. Geodetic radius of the Earth at this latitude
is 6370.8 ݇݉km. Surface level of the Caspian Sea is approximately equal to the mean sea level


i know the condition of a star being circumpolar is that it's latitude should be greater than declination? is it only applicable to altitude=0m or with all altitudes?

please give me some initial guidelines to solve it out...
 
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hi trina1990! :smile:
trina1990 said:
What is the minimum declination for a star, to be seen
marginally circumpolar for this observer.

doesn't it just mean what is the declination of a star sitting due north on the water?
 
thanks for answering...
of course it's that, but my question is how can i explain this procedure mathematically?...

i just wanted to know the process of measering star declination &then asked if the circumpolar condition changes if i change the altitude?

for circumpolar stars i only know their latitude should be greater than declination...how can i use this info to walk through this problem?
 
hi trina1990! :smile:
trina1990 said:
for circumpolar stars i only know their latitude should be greater than declination …

no, because you're on a mountain top, so you can see stars that are lower than usual :wink:
 
well, so there altitude matters...i can see the stars below horizon due to my high altitude & refraction on the atmospheric layers...

but can you please suggest me the clue to derive this declination?
 
all you need to know is the angle below horizontal from the mountain to the horizon …

so draw a diagram! :wink:
 
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