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Are Time and Distance Precise?

Today is Lunar parigee (Supermoon) and I was hoping to photograph the Moon at precise parigee.  According to Starry Night Pro, that will occur at exactly 12:46:14 local time with a lunar distance of 353,254.5 km.  This data does not correspond with other data available on the Web which indicates (several sources) parigee will occur at 4:09 am (local) with a minimum distance of 357,014 km.  My location was selected from the SNP database and my computer/SNP time is correct.  I have tried entering coordinates manually but the results are virtually identical.  I understand that I'll probably never get it exact to the second but the event times aren't even close and while I know a difference of 4,000 km and 3+ hours is miniscule in terms of the universe, it's pretty significant when attempting to calculate parigee.

I hope you can tell me what I'm doing wrong.

Thanks in advance,


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