“How long is one year?”

What’s the answer to that question? Most of us would reply, “365 days,” but we wouldn’t necessarily be correct. While we’ve been trained and told to round to 365 days, the measurement of a year is much more complex than a simple number. First of all, how do you measure it accurately? It’s not as if we can put a line in space and keep a stopwatch until we get to it again. We’re not on a stable, measured track. In fact, the question, “How long is one year,” only gets more complicated the further we dig into it.

What about leap years? Most of us recognize that ‘one year’ is not exactly 365 days, but is in fact a few hours, days and minutes longer. Rather than adding this extra time every year, however, we compile it into a leap year – really a leap day at the end of February – once every four years. This primitive jury-rigging of the gregorian calendar might nudge it back into place, but it still doesn’t answer the question, “How long is one year?”
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