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CCSDS 850 spacecraft time access service

it's bit outdated, but the concept should still be relevant so Mission Elapsed Time (MET) is a count, based on free-running local reference time, and a "snapshot" time of lift off event. Now this CCSDS is superseded by ISO17214 CCSDS document

starliner OFT

“We’re moving into a new era,” Jim Bridenstine said 19 Dec 2019. “We are going to launch American astronauts, on American rockets, from American soil for the first time since the retirement of the space shuttles.”  animation and objectives Boeing Starliner made a smooth launch on 20 Dec, 2019. But failed to reach ISS. It was found due to Mission Elapsed Timer error. The spacecraft’s mission elapsed timer, which is set by communicating with its Atlas 5 rocket prior to liftoff, was off by 11 hours. That caused the spacecraft to think it was on the wrong phase (ISS Station proximity ops) of its mission after separation from the rocket’s upper stage, triggering thruster firings that used excessive amounts of fuel until ground controllers could take over and turn off the thrusters. After being released by the rocket(MECO), Starliner was supposed to use its Orbital Maneuvering and Attitude Control engines to provide the thrust needed to reach a stable orbit(1) and begin ...