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."

Brian Tung
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