"Brian Tung" wrote in message
...
Chris L Peterson wrote:
Or so- it varies by more than 10% over the range that aircraft fly. I'd
agree with Thierry here- the usage is just plain wrong, and it's fair
to call them on it. If they said "faster than the speed of sound on
Earth" or something similar, I'd say fine (that isn't real precise, but
it's okay with a popular science article). But "Mach" has a precise
meaning, and its usage in the article makes things more confusing, not
less.

If all they wanted was to convey the high speed, all they had to do was
use 750 miles per hour (or whatever it really was). Most people will
understand that that's fast, and if they want, they can say "about the
speed of a supersonic jet."

Hi,

Of course that everybody undertood what NASA meant, and most even don't
noticed this error.
But such sentences are published in official publications signed by two or
more investiogators of cassini team and released as PDF on various websites
dealing with the Cassini-Hygens missions. Those text are usually addressed
to advanced readers.

If they can speak technics with many details, most requesting a deep
knowledge in the field (e.g.they speak of correlator and bandwidth that need
some knowledge in radioastronomy or electronics, fusion and boiling point of
methan, that request some knowledge of chemistry, etc) they can also take
care to their vocabulary and use the right word at the right time.
Mach 1.5 on earth or on Titan are not exactly the same for a specialist.

Found such errors in documentation checked by several chief investigators at
NASA is not acceptable.

Thierry
http://www.astrosurf.com/lombry/titan-brumes.htm



Brian Tung
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