Convert from cana (canna, canne) to petameter

Unit Definition (cana (canna, canne))
The caña (canna, canne) are traditional units of distance in Spain, Italy, and southern France, respectively. The caña varied in size, but it was most often defined as 8 palmos, which makes it the Mediterranean version of the fathom, equal to roughly 2 meters or 6.5 feet. In Italy a measuring stick is still called a canna metrica. The unit is sometimes translated to "rod" in English, but "fathom" is the proper choice.

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.