This conversion is rarely used in everyday life but can be helpful in specialized scientific contexts, like theoretical physics or cosmology, to compare extremely small phenomena with vast cosmic distances.

5,000,000 nanometers is equal to 5 millimeters, or about the thickness of a few credit cards stacked together.

A light-year is about 9.46 trillion kilometers (5.88 trillion miles). It's the distance light travels in a vacuum in one Julian year.

Yes, because a light-year is such an enormous distance, even a relatively large number of nanometers becomes an infinitesimally small fraction of a light-year, effectively rounding down to 0.0000 for most practical purposes.