Question

A star of declination 42◦ 21` N is observed when its hour angle is 8h 16m 42s. If the observer’s latitude is 60◦ N, calculate the star’s azimuth and altitude at the time of observation.

Answer 1

https://www.AssignmentExpert.com

Answer on Question #54951, Physics / Astronomy | Astrophysics

Question:

A star of declination $42{}^{\circ} 21'$ N is observed when its hour angle is 8h 16m 42s. If the observer's latitude is $60{}^{\circ}$ N, calculate the star's azimuth and altitude at the time of observation.

Solution:

It is often a great help to sketch as accurately as possible a celestial sphere diagram of the problem.

This provides a visual check on deductions about quadrants in which an angle lies. Since $\mathrm{P_X} = 90 - \delta$, we see that its value is $47{}^{\circ}39'$.

We convert the hour angle value of $8^{\mathrm{h}}16^{\mathrm{m}}42^{\mathrm{s}}$ to angular measure by means of table:

$$8 ^ {\mathrm {h}} 1 6 ^ {\mathrm {m}} 4 2 ^ {\mathrm {s}} = 8 ^ {\mathrm {h}} + 1 6 ^ {\mathrm {m}} + 4 2 ^ {\mathrm {s}} = 1 2 4 {}^ {\circ} 1 0. 5 ^ {\prime}$$

Answer: 124°10.5'