|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
A cable length or length of cable is a nautical unit of measure equal to one tenth of a nautical mile or approximately 100 fathoms. The unit is named after the length of a ship's anchor cable in the Age of Sail. The definition varies:
The light-hour is a unit of length useful in astronomy, telecommunications and relativistic physics. It is defined as the distance that light travels in free space in onehour, and is equal to exactly 1.0792528488×1012 metres.