This puzzle is about misunderstanding and/or misapplying ‘facts’ and about the dangers of mixing ancient knowledge with modern understandings.
When one is north of the Arctic Circle, there are nights in the summer when the sun stays above the horizon (doesn’t set), and days in the winter when it never rises above the horizon (no sunrise). A similar situation arises as one approaches the South Pole.
I originally choose Resolute Canada because it is well above the Arctic Circle. It does have days of noontime darkness in winter and days of midnight sun in summer, but it is not far enough north.
So, I changed his location to the North Pole (no reference to St Claus intended). Here, the sun sets at the autumnal equinox (around September) and rises as the vernal equinox (around March). So, buy a strict misapplication of the Hebrew definition, a full day runs from autumn to autumn.
When I mentioned that the person waiting for spring came to the ‘realization’ that spring would be later that same day, it is because he realized that according to the (misapplied) Hebrew definition, it would still be the same day when spring came.
Then, he continued to misapply this knowledge. Taking this ‘fact’ that there is one ‘day’ per solar year, and the modern ‘fact’ that there are 365.25 days per calendar year, he divided 2017 (the number of solar years since Christ) by 365.25 (the number of calendar days in a calendar year) and came up with a little over 5.5 years.
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There are a number of other anomalies having to do with the Hebrew definition, particularly when attempting to use modern thinking to understand them. For example:
Since hours are a division of daytime and/or nighttime periods, (the time between sunrise and sunset is divided by 12 to get the hour) and similar for night, an hour is not a standard increment of time. During the summer, an hour of day is longer than an hour of night, since the day is longer than the night. But in winter, the nights are longer than the days, and an hour of winder night is longer than an hour of winter daytime.
The only point here to the original question of how long a time was a Genesis day (or YOM) is that we should be careful in using modern methods to study ancient knowledge.