[X] My Assistant

[mcaplinger]

From the spacEurope Peter Smith Q&A:
Q: using the MARDI camera has been cancelled. Do you think that the MARDI microphone will be used later on in the mission to record some sounds?

A: The MARDI instrument was found to interfere with the guidance system under rare circumstances forcing the difficult decision to turn it off during the descent. The microphone does work and may be used later in the mission to hear the sounds of the RA scraping on the Martian ice.

[To clarify this answer: the card in the Lockheed-Martin spacecraft computer that handles MARDI data also handles guidance system data, and the problem was with this card, not with MARDI itself.]

From the spacEurope Barry Goldstein Q&A:

Q: Will MARDI and the Mic be used post-landing at all?

A: The MARDI will not be used.

Goldstein's answer certainly sounds definitive and final.

So, best of luck to Phoenix, a mission I used to have something to do with.

Disclaimer: this is all information from public sources. Opinions, if any, are my own.

[MarsEngineer]

Hi Mike,

It is sad that we will not acquire MARDI images during "terminal descent" (landing). To be clear (as you know), the "interference" that was mentioned was not due to the MARDI instrument itself, rather it was due to a very hard to find bug in an interface chip in an electronic board inside the lander unrelated to MARDI. It was discovered (before launch) that during the MARDI image data transfer the chip design was susceptible to errors that had the unfortunate consequence (in rare cases) in causing the lander computer to reset during EDL. Phoenix (and MSL) are not able to survive landing in the event that the on-board computer resets. If it did, by the time that the reboot is complete, too many things have happened for the software to be able to figure out what to do to survive. Although the odds of a reset was on the very low side, it was decided that we should not take a chance that it would.

I am happy to say that we expect to take (lots) of images with MARDI during MSL's landing. The chip design problem will be gone by then. (I certainly hope!)

-Rob Manning

PS GO PHOENIX !!!!!

*******
Opinons are those of the author and do not represent the views of JPL, Caltech nor NASA

[climber]

Thanks for the precision to you both... but I must admit that I've not understood for sure whether or not microphone will be used once on the ground!

Ok, I know where you'll be, Rob, for MSL EDL but, if both of you permit such a inquisitive question, what about this topic answer?: http://www.unmannedspaceflight.com/index.p...mp;#entry114229