Neptune-Pluto Cycles are long in human terms: 495 years, give or take 2-3 years. So why blog about a cycle that way exceeds our lifetimes? Perspective.

Cycles within Cycles

 
Every 495-year Neptune-Pluto cycle contains four Uranus-Pluto and three Uranus-Neptune cycles. 
The synodic cycle between Neptune and Pluto is a little different. The span of the first and third phases 
last 172 years; the second and fourth, 72 years.