This Columbia mission was identified as STS-107. And yet, I heard reference to the fact that STS-112 was two missions prior! What does “STS” mean, and why aren’t the numbers consecutive?
- Jinx
“Space Transportation System”.
It stands for “Space Transportation System” (seems a gratuitous use of a TLA if ever there was one), and as it says here, the number designations are made up years in advance, so by the time the actual flight occurs, lots of changes have been made and it probably got bumped around.
This seems to be the official listing of shuttle flights, with pictures and stuff.
I prefer this other archive (both are NASA) because it seems less flashy, more facty.
As for numbering, that could be that the flight numbers are assigned at a much earlier time but a delay due to a mechanical problem might cause a rescheduling. Remember, the flights are planned years in advanced, and unscheduled delays can have an adverse impact on various experiments and payloads that may have a small launch window that in turn delay a deployment from hours (hooking up to space station) to years (interplanetary probe).
Space Transportation System was the original name of the Space Shuttle Program. Sure, they called it the Space Shuttle, but the whole launch system involves the external tank and the solid rocket boosters as well.
Not only that, but missions are sometimes combined or scrubbed altogether because of funding cuts and the such.