Archived Calculating the optimal day to observe an object given the RA and dec

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To determine the optimal day to observe OmegaCen, which has coordinates R.A. = 13h26m45.89s and Dec = −47°28′36.7′′, the calculation involves adjusting the right ascension (RA) to find when it is directly overhead at midnight. This adjustment results in an RA of approximately 1.446 hours, leading to an estimated observation date of about 20.75 days after the vernal equinox, which falls around April 10.75. The interpretation of 10.75 suggests that the observation should occur at the beginning of April 11. It is noted that the exact timing may vary slightly based on time zone considerations. Therefore, April 11 is deemed an appropriate date for the observation.
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Homework Statement



OmegaCen is a Globular Cluster which lies at coordinates: R.A. = 13h26m45.89s,
Dec = −47°28′36.7′′ (J2000.0) estimate the optimal day on which to observe
this object.

Homework Equations





The Attempt at a Solution



We are to interpret optimal as 12 am midnight directly overhead

since this is 12 hrs after noon you subtract 12hrs RA = 1hr26m45.89sec
which is ≈ 1.446 hrs RA and this is due to the monthly RA shift
2 hrs of RA shift per month so, 30/1.446 ≈ 20.75 days
so 20.75 days after the vernal equinox, which is april the 10.75 th
im not quite sure how to interpret the 10.75, do i say its on the 10th of april or the 11th ? and the observation is meant to be at 12 am midnight so would you say its on the 11th april? (at the very beginning). Thank you!
 
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The vernal equinox probably won't happen exactly at midnight, but that depends on the time zone... April 11th should be fine.

(see https://www.physicsforums.com/threads/read-me-how-to-use-this-forum.855656/ why you suddenly get an answer for an old thread)
 
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