yd yard
mile 5280 feet
mi mile
-nautical 1.151 # For `nautical mile'
+#nautical 1.151 # For `nautical mile'
+nautical 1.150779447892
parsec 1.91615e13 mi
+#parsec 3.08568025e16 m # better?
# light year will be implied by `year' and `light' below
fathom 6 ft
cable 120 fathoms