Thanks, Joseph. Quite right.

We are among the last generation not to have been brought up with 100%
metric schooling, so little errors are inevitable!

Regards

Mike

----- Original Message -----
From: "Joseph B. Reid" <[EMAIL PROTECTED]>
To: "U.S. Metric Association" <[EMAIL PROTECTED]>
Sent: Friday, November 15, 2002 11:38 PM
Subject: [USMA:23384] Re: Astronomical distance measures


| The JPL press release is worse than Mike Joy realized when he wrote
| USMA 23374.  He said:
| >
| >"However, your use of "billions" should be relegated to the old
customary
| >units, as the term "a billion miles" means absolutely nothing to anyone
| >other than "a long, long way".
| >
| >"Today in the 21st century we are all familiar with metric prefixes as
we
| >use them every day, e.g. kilo for "a thousand" (kilogram), milli for "a
| >thousandth" (millimeter), Mega for "a million" (MegaHertz), cent for
| >"hundredth" (cent coin), Giga for "a thousand million" (Gigabyte) and so
| >on.
| >
| >"May I persuade you to consider using suitable prefixes for very large
| >distances in order to make them more meaningful? Your statement "1.6
| >billion km" would be better stated as 1.6Tm (to use the correct
| >terminology, i.e. Terameters), or at least you could use "xxx times the
| >distance from the Earth to the Sun", or other suitable astronomical
| >measuring terminology."
| >
|
| In many countries "1.6 billion kilometers" would be understood to
| mean "1.6 Pt" (petametres).  If you use billion, trillion,
| quadrillion, etc. you risk being misunderstood in half the world.
|
| Term     American meaning Euopean meaning
| ------   ----------------       ---------------
| billion     10^9    10^12
| trillion    10^12    10^18
| quadrillion 10^15    10^24
| "Billion" is a contraction of "bi-million".
|
| If you will allow me to split a hair, those prefixes are mega, giga,
| tera, etc., not Mega, Giga, Tera, etc.,  It is their symbols that are
| an upper-case letter.
|
| Joseph B. Reid
| 17 Glebe Road West
| Toronto  M5P 1C8 Telephone 416-486-6071
|
|

Reply via email to