Data channel "glitch" on Huygens

I still do not have a clear picture of exactly what was lost due to the
glitches with the data channel on Huygens. Most reports just barely mention
the glitch and most do not even mention it and none are clear on just what
data was lost and what was recovered, and how it was recovered.

Some seem to indicate that nearly nothing was lost due to the fact that the
channels were redundant and the data was duplicated over both channels.
Others seem to indicate that the "recovered" data was due to the
"eavesdropping" of the earth-based radio telescopes. Yet other reports seem
to indicate that half (some 350 of 700) the images were completely lost (and
not recovered by some other means such as redundancy of channels or
eavesdropping from earth).

Can anyone shed some light on these issues and why the media seem shy to
dwell more on these matters as well on the notable successes of the mission.

Spaceflightnow.com has details.

Basically, with 2 comm channels, the engineers had a choice of sending
all data twice (once on each channel) or sending twice as much data,
half on each channel.
They chose to send twice as much data (700 photos instead of 350), so
when the link with one channel failed, half the photos were lost.

Actually, I have since found an interesting story about the glitch and what
transpired.
See at http://www.spectrum.ieee.org/WEBONLY...5nhuygens.html


"hankman" wrote in message
.. .
I still do not have a clear picture of exactly what was lost due to the
glitches with the data channel on Huygens. Most reports just barely
mention
the glitch and most do not even mention it and none are clear on just what
data was lost and what was recovered, and how it was recovered.

Some seem to indicate that nearly nothing was lost due to the fact that
the
channels were redundant and the data was duplicated over both channels.
Others seem to indicate that the "recovered" data was due to the
"eavesdropping" of the earth-based radio telescopes. Yet other reports
seem
to indicate that half (some 350 of 700) the images were completely lost
(and
not recovered by some other means such as redundancy of channels or
eavesdropping from earth).

Can anyone shed some light on these issues and why the media seem shy to
dwell more on these matters as well on the notable successes of the
mission.

See also the following about how they discovered the original problem:
http://www.spectrum.ieee.org/WEBONLY...1004titan.html

"hankman" wrote in message
...
Actually, I have since found an interesting story about the glitch and
what
transpired.
See at
http://www.spectrum.ieee.org/WEBONLY...5nhuygens.html


"hankman" wrote in message
.. .
I still do not have a clear picture of exactly what was lost due to the
glitches with the data channel on Huygens. Most reports just barely
mention
the glitch and most do not even mention it and none are clear on just
what
data was lost and what was recovered, and how it was recovered.

Some seem to indicate that nearly nothing was lost due to the fact that
the
channels were redundant and the data was duplicated over both channels.
Others seem to indicate that the "recovered" data was due to the
"eavesdropping" of the earth-based radio telescopes. Yet other reports
seem
to indicate that half (some 350 of 700) the images were completely lost
(and
not recovered by some other means such as redundancy of channels or
eavesdropping from earth).

Can anyone shed some light on these issues and why the media seem shy to
dwell more on these matters as well on the notable successes of the
mission.