Convert from spat to millimicron

Unit Definition (spat)
The spat is an informal unit of distance formerly used by astronomers. The spat is equal to the terameter (Tm, or 10E12 meters). This is equivalent to about 6.6846 astronomical units. The origin of this usage is not clear; "spat" may be an acronym for "space unit" or "space-time".

Unit Definition (millimicron)
A unit of metric measurement 1000 millimeters equal one meter, 10 millimeters equal one centimeter, about 25 millimeters is one inch.