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UCAC2 Star in Sky Safari?

How does one search for a star in Sky Safari 5 Pro on an iPad or iPhone that has a designation of

2UCAC 38742909

The current response is "not found".  I am assuming that I am not specifying the star designation properly.

Thanks, DAC


  • 0
    Bill Tschumy



    We don't have the UCAC catalog in SkySafari so you won't find it by search that way.


    Often, if you have a designation that is not found in SkySafari, you can look the object up in SIMBAD to see if there is an alternate name that we might have it under.  In this case, the designation is not even in SIMBAD (which is unusual).

    It does indicate the object was found in the VizieR database.

    This indicates it is a 10th magnitude star in Taurus.  I question whether this is correct. Such a bright star would certainly have other designations and be in or database.  What is this object?  Where did you get the catalog number?

  • 0
    Dan A. Chrisman Jr.


    Thanks for the quick reply.  In addition to having used and continue to use Sky Safari for my Astroleague observing programs, I have begun attempting to use it with my novice-level participation in the International Occultation Timing Association (IOTA) events.  One category of their focus is observing an asteroid occulting a star.  To date, I have been able to find in Sky Safari each asteroid of interest.  However, on multiple occasions, I have failed to find the associated star.  Per my original question,

    " IOTA/IOTA-ES occultation update for (803) Picka / 2UCAC 38742909 event on 2017 Jan 17, 04:32 UT

                                Visible from USA, Mexico                            
    On 2017 Jan 17 UT, the 47 km diameter asteroid (803) Picka will occult a 11.9 
    mag star in the constellation Taurus for observers along a path across USA, 
    In the case of an occultation, the combined light of the asteroid and the star 
    will drop by  2.97 mag to 14.80 mag (the magnitude of the asteroid) for at most 
    8.8 seconds."
    Like you, I was unable to find an alternate star name. And the IOTA data indicates that
    the star is a much fainter 11.9 magnitude than the 10th magnitude that vizier indicates.
    So, is the UCAC2 or subsequent catalogs too costly to include in Sky Safari?
    Or just not in demand?


  • 0
    Bill Tschumy

    I don't know what else to say about this.  This star is fairly bright but seems to only have a UCAC2 designation.  That's somewhat strange.  Do you know if anyone actually saw the occultation?  Is the star real?

    If the IOTA only gives the UCAC2 catalog then SkySafari will not so useful to you.  If you look up the star's RA/Dec in SIMBAD (or VizieR), you can have SkySafari go to that RA/Dec so you at least know it is in the field of view.

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