Convert from pes to light year

Unit Definition (pes)
The pes is the Roman foot, equal to 29.67 centimeters (about 11.68 inches). The pes was divided into 12 unciae (inches). There were 5 pes (or pedes) in 1 passus (pace, see above), 10 in a decempeda, 625 in a stadium, and 5000 in the Roman mile.

Unit Definition (light year)
The distance that light, moving at a constant speed of 300,000 km/s, travels in one year. One light year is about 10 trillion kilometers.