Spat (unit)
The spat (symbol sp), from the Latin spatium ("space"), is a unit of solid angle. 1 spat is equal to 4π steradians or approximately 41253 square degrees of solid angle. As such, it is the solid angle subtended by a sphere at its centre.
The spat (symbol S) is also an obsolete unit of distance used in astronomy. It is equal to 1000000000 kilometres (1 Tm or 1012 m). It is about 6.6846 astronomical units (AU),1.057×10−4 light-years or 3.240×10−5 parsecs.
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