Mro On Approach, TCM-3 not required Options

[Redstone]

MRO has shifted from the cruise phase to Approach phase. Apparently, the trajectory is so good that TCM-3 was cancelled. This is good news for the prospects for a long life for MRO supporting future missions. TCM-4 is on Feb 28, and MOI on March 10. Only 5 weeks away!

[edstrick]

On it's second lunar day, JPL tried to get Surveyor 6 to wake up and transmit. Surveyor's 1 and 5 had operated successfully on the second (and for 5, later) lunar days, despite cold damage.

Surveyor 6 transmitted signal briefly, then went silent. While they were attempting various commands, switching systems in the blind, Surveyor 1 (which had the same receiver frequency) woke up instead on it's 7'th lunar day and briefly transmitted. I don't recall for sure, but I don't think they got interpretable telemetry from either of them during the attempts.

Surveyor 7 also was successfully operated during it's second lunar day.

Lunar Orbiter 1 was deliberately crashed at the end of it's extended mission to clear up a communications frequency.

[ugordan]

Don't the DSN uplink commands have a sort of digital signature as well as intended receiver "address" in their packet headers so that Spirit/MRO know the transmission is directed towards them specifically?
That would sure seem a logical and sensible thing to do. What would otherwise prevent, say, ESA's New Norcia DSN station to "accidentally" transmit garbage on channel 32 and screw up both probes at once?