Reason: The velocity calculation in the code had raw velocity “R” instead of smooth velocity R BAR.The programmer had carefully implemented the minutest details of every specification needed though missed putting a hyphen on top of R used for velocity calculation.it is termed as the costliest hyphen in history…!
Estimated loss:2.2 billion USD
The year was 1992 and Mars Climate Orbiter reached Mars but was lost after it entered into the atmosphere..
Reason:The mission involved involved two firms,The Jet Propulsion Laboratory and Lockheed Martin Astronautics which were at two different places and also used two different units.As a result the ground software used metric units(Newton seconds ) instead of English units (pound seconds).
Estimated loss:18.5 billion USD