# Spherical astronomy

1. Feb 26, 2013

### Numeriprimi

This homework is for someone who understands the spherical astronomy and physics. I do not understand subject matter. I can do the basics - I know some kinds of coordinates, but that's all. Please be very patient with me.
1. The problem statement, all variables and given/known data
Astronomer observing the sky with a small telescope by hole at the observatory in the middle of dome (lens diameter is much smaller than the diameter of the dome). Calculate the maximum time when astronomer can still observe objects near the celestial equator, without having to rotate the dome. Which side of the world will it be?
Diameter dome: 5m, width hole: 1m, latitude: +50 °

2. Relevant equations
Hmmm... Basic equations of spherical astronomy: sidereal time star = RA + hour angle.

3. The attempt at a solution
hour angle = sideral time star - RA
In addition, however, I do not know, I do not understand those coordinates. How do I determine the two variables?
Then we would use the equation, if we know that the star culminates between zenith and world pole.
zenith distance = 180 ° - (latitude + declination)

However, that's all, I looking at the formula for a long time, but still do not understand. Please help. Thank you.

And sorry for my bad English.