Tuesday, May 27, 2008

You Win Some and You Lose Some

On the heels of a very successful first day after landing, we experienced a glitch with our radio. Something appears to have gone wrong at the beginning of a recording session this morning. I came in to work, looked at the spacecraft telemetry, and immediately scratched my head. The spacecraft was using a different clock than the one normally provided by the UHF radio, and the radio was powered down. In addition, a bunch of "red alarms" had been tripped in the telemetry and things looked wacky.

I arrived just moments after it happened, so was on the ground floor during most of the early discussions. At this time, we're looking to power the radio back on, as we believe it is safe to do so, and we will attempt to perform the relay sessions with Phoenix we have planned for later this afternoon. While that's going on, our radio and spacecraft people will continue to look at the telemetry gathered during the "event", in hopes of figuring out what it is.

In the meantime, this glitch cost the Phoenix project an entire day in their mission, if not more. With only 90 days to spend, that hurts. The overflight was their primary commanding session for the next day of activities, and we expected to return a lot of data to them for analysis, as well. Instead, they will have to wait for the next opportunity to command via Odyssey and will have to queue up the data to be transmitted via Odyssey until we can say for sure that MRO is up and reliable again. Hopefully we'll get to the bottom of it, soon, but while we're zeroing in on the problem, we're not there, yet.

I was thinking today was going to be boring, too. Hah!


Denis said...

That's not a great way to start the day. How many passes per sol do MRO and Odyssey make that have significant windows for comm? Are they distributed through the sol in such a way as to be able to pick up a missed uplink or downlink on the next pass of the other machine? I think I heard your data xfer rate was around 128k? What is the approximate frequency and power for Phoenix's transmitter?

Roy said...

Both orbiters "see" Phoenix 12 to 13 times a day since they're so far north -- there's usually only two or three higher-elevation passes per Sol, though. We do usually receive data from PHX at 128 kbps, but transmit only at 8 kbps. Kinda slow, for sure, but you can still pump an awful lot of data through a link like that. Can't tell you the frequency and power, though -- sorry, ITAR restricted ... ;)

Denis said...

DDTC told me to ask. You passed! :^D

Anonymous said...

How are things looking?

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