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MSL Landing Timeline: What To Expect Tonight
An anonymous reader writes "When the Curiosity rover lands on Mars later tonight, it'll be executing a complex series of maneuvers. JPL will be relying on the Mars Odyssey orbiter to relay telemetry back to Earth in time-delayed real-time, and if all goes well, we'll be getting confirmation on the success (or failure) of each entry, descent, and landing phase, outlined in detail here."
Telemetry will be continuously relayed back to earth, true, but with not much less than about a 15 minute latency, owing to the fact that Mars roughly a quarter of a light-hour from earth right now.
That IS indeed real time. Relativity tells us nothing can have an effect here in less time. I don't know if you're trolling or just ignorant, but by your definition you can never look at the stars, galaxies or nebulae in the sky in real time either because they're all at varying distances and we're seeing light that originated anything from about 4 to several million years ago. With telescopes you can go back billions.
You draw the line at any signal latency that is too slow to meaningfully respond to in the context that the signal was originally sent from. There's a reason why interrupt handlers in real-time OS's need to finish their job in as few computing cycles as possible.
File under 'M' for 'Manic ranting'
Owing to the fact that we will know the lander has already reached the surface (in unknown condition) by the time we get the first signal it has entered the atmosphere
Relativity says that there is a 14 minute delay in *some* frames of reference. In other frames of reference, the delay is longer. For others (those occupied by the radio signal photons, for example), the landing events and our reception of the signals happen simultaneously.
Getting hung up over what you imagine is the "time delay" between two points in spacetime that are outside of each others' light cones is kind of pointless.