Understanding RA & Declination

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  • Member since
    November, 2013
Understanding RA & Declination
Posted by AdamLink on Tuesday, November 05, 2013 12:57 AM

I was given an astronomical position as follows:  

RA - 13 N 23, Declination 187.42 22

I have a formula that requires me to enter the RA as hrs/min/sec, and the Declination as deg/min/sec

Can someone help me to convert my given data into data I can use in the formula?


Thank  you.



  • Member since
    November, 2009
Posted by Poppa Chris on Tuesday, November 05, 2013 10:28 AM

Are you sure you have the data correct?  RA should be in Hrs-Mins-Secs and Declination in Degs-Mins-Secs (or the decimal equivilents thereof)

---Poppa Chris---

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"Second star to the right - Then straight on until morning!" - Peter Pan

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  • Member since
    May, 2005
Posted by Centaur on Tuesday, November 05, 2013 11:39 AM
Welcome to the discussion group, Zane. 
Your posting appears to have inverted the data for Right Ascension and Declination. Declination is never greater than 90°, and Right Ascension does not include N (north) or S (South) designations. 
The figures 13 N 23 probably mean North 13°23’ (+13.38°) declination. The figures 182.42 22 are apparently Right Ascension in degrees rather than hours, and probably mean 182°42’22” (182.7061°). That’s equivalent to 12:10:49 (12.1803) hours. 

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  • Member since
    October, 2007
Posted by Aratus on Tuesday, November 05, 2013 1:43 PM

. . . and what is there exactly?    It seems pretty barren to me. 


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