why is the value of mu=0.012277471 vs. mu=.0121505 (?)

[rslippert]

For CR3BP problem, most people are using mu=.0121505845
But the value in this code is mu=.012277471
IE. Is there something about this difference I need to understand?

NASA has calculated mu from highly accurate earth _ moon mass ratio = .0123000371
so, mu = .0123000371/1.0123000371 = .0121505845