On Sat, 07 Jul 2007 14:57:04 -0500, Logan Shaw
wrote:
wrote:
On Jul 7, 7:29 am, "HeyBub" wrote:
Hmm. 12:00PM implies twelve hours past midday (p.m. = "post meridian" = past
midday). That would be midnight. From there to 7:46PM means the ac has been
on for almost twenty hours.
Of course one could also say 12:00AM (a.m. = "ante meridian" = before
midday) which would also be midnight.
Sorry, 12:00PM is noon. Have a High School diploma?? Is English your
native language??
I have a high school (and college) diploma. Yet, I don't think everything
I heard in high school (or college) is automatically true. In particular,
2000 wasn't the first year of the new millenium, and 12:00 PM is not noon.
Here's an explanation of why:
http://tf.nist.gov/timefreq/general/...m#Anchor-57026
This is so on-point, I think it deserves to be quoted. Also, I don't
think there can be copyright issues with government websites info, all
of which should be in the public domain"
Are noon and midnight 12 a.m. or 12 p.m.?
This is a tricky question. The answer is that the terms 12 a.m.
and 12 p.m. are wrong and should not be used.
To illustrate this, consider that "a.m" and "p.m." are
abbreviations for "ante meridiem" and "post meridiem." They mean
"before noon" and "after noon," respectively. Noon is neither before
or after noon; it is simply noon. Therefore, neither the "a.m." nor
"p.m." designation is correct. On the other hand, midnight is both 12
hours before noon and 12 hours after noon. Therefore, either 12 a.m.
or 12 p.m. could work as a designation for midnight, but both would be
ambiguous as to the date intended.
When a specific date is important, and when we can use a 24-hour
clock, we prefer to designate that moment not as 1200 midnight, but
rather as 0000 if we are referring to the beginning of a given day (or
date), or 2400 if we are designating the end of a given day (or date).
To be certain of avoiding ambiguity (while still using a 12-hour
clock), specify an event as beginning at 1201 a.m. or ending at 1159
p.m., for example; this method is used by the railroads and airlines
for schedules, and is often found on legal papers such as contracts
and insurance policies.
=== I've heard this before.
If one is referring not to a specific date, but rather to
several days, or days in general, use the terms noon and midnight
instead of 12 a.m. and 12 p.m. For example, a bank might be open on
Saturdays from 8 a.m. to noon. Or a grocery store might be open daily
until midnight. The terms "12 noon" and "12 midnight" are also
correct, though redundant.
==== On July 3, I was a at a supermarket that had a temporary sign,
and someone had written "Open July 4, 7AM to 12AM, and then it had a
dark P written over the second A.
Note that this comes from NIST, the National Institute of Standards
and Technology, which is the US federal government agency responsible
for standardizing measurements.
I liked it better when it was the National Bureau of Standards. They
keep changing names and confusing me. (I'm just going to call the INS
"la Migra" so I don't have to worry when it changes names.)
These are the people who operate
NIST-F1, the atomic clock which is the primary reference for timekeeping
in the United States, and one of the primary references worldwide.
I'll tell you how I remmeber this, and how I think it arose. The
moment of noon is neither before noon or after noon, but the
59.999999999...... seconds after that are after noon, and yet still
part of the minute that is 12:00. (and part of the second that is
12:00:00.) So even though all but the tiniest bit of the minute is not
noon, most of 12:00 noon is PM.
- Logan