I suspect that precision is reporter stupidity
They just translated from one unit system to another and put in extra decimal places. The same way that we all have branded on our memories that human body temperature is 98.6F when it varies by a couple of degrees from person to person and through the day. Truth is it was measured as 37C and then people converted that exactly.
That said, I am wondering how they produced a diameter...
Cheers,
Ben
"... I couldn't see how anyone could be educated by this self-propagating system in which people pass exams, teach others to pass exams, but nobody knows anything."
--Richard Feynman