Convert from button measure to petameter

Unit Definition (button measure)
The button measure is a unit of distance equal to 1/40 inch (0.635 millimeter), used to measure the thickness of buttons.

Unit Definition (petameter)
The petameter is a metric unit of distance equal to 10E12 kilometers. This is equivalent to about 621.371 billion miles or 0.1057 light year. The distance from the earth to the nearest star (other than the sun) is about 40 petameters.