Is Midnight Considered PM, AM, or Neither?

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Midnight is a point of confusion, often debated whether it is classified as AM or PM. Technically, it is neither, as AM (Ante Meridian) means "before midday" and PM (Post Meridian) means "after midday." Midnight, occurring at 12:00, does not fit neatly into either category, leading to the argument that it should simply be referred to as "midnight." In practical terms, many systems, including computers, designate midnight as 12:00 AM, marking the start of a new day, while noon is designated as 12:00 PM. This distinction can lead to misunderstandings, especially in contexts like sales promotions that reference midnight. The discussion also highlights the preference for a 24-hour time system, which could eliminate such ambiguities. Ultimately, while midnight is often treated as 12:00 AM in everyday use, it is recognized that it is technically a moment that exists outside the AM/PM classification.
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Is midnight PM or AM? Does midnight end the previous day, or begin the next day? I have read that midnight is PM or AM, I have read that midnight is neither PM nor AM, it is a moment of no time. I have read that computers calculate midnight as 12:00 AM, and noon as 12:00 PM. I am very confused. The reason why I ask this is to try to disprove a sign at a local video store, hehe. Please answer this is you know the answer.

Thanks in advanced. :smile:
 
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My logic has always been that the 12 represents a the start of a new hour, so it needs to be different from 11:59. Therefore 12:00AM must follow 11:59PM and 12:00PM must follow 11:59AM. Likewise it could be said that there is no doubt about 12:01, so simplicity says that we should make 12:00 am if 12:01 is am.

By this logic 12AM is midight and 12PM is noon.
 
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Midnight= 12:00 AM
 
Noon = 12:00 PM
 
MidNoon = 12:00 HM
 
midnight is 00:00 hours, thus AM :rollseyes:


but technically 00:00 on the 25th December is equivalent to 24:00 on the 24th December.. :rolleyes:
 
wats the sign at the video store say?
 
Gamish said:
Is midnight PM or AM? Does midnight end the previous day, or begin the next day? I have read that midnight is PM or AM, I have read that midnight is neither PM nor AM, it is a moment of no time. I have read that computers calculate midnight as 12:00 AM, and noon as 12:00 PM. I am very confused. The reason why I ask this is to try to disprove a sign at a local video store, hehe. Please answer this is you know the answer.

Thanks in advanced. :smile:

It turns out your confusion is justified :-p because it is technically improper to refer to the 12 o'clock hour as AM or PM.

AM stands for Ante Meridian, which is Latin for: before midday

PM stands for Post Meridian, which is Latin for: after midday

At 12 o'clock it is neither before midday nor after midday (midday stands for middle point, not really "day"). The proper terms for the two 12 o'clock hours are midnight and noon; then a second past either it is 12:00:01 AM or 12:00:01 PM, respectively.
 
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Les Sleeth said:
It turns out your confusion is justified :-p because it is technically improper to refer to the 12 o'clock hour as AM or PM.

AM stands for Ante Meridian, which is Latin for: before midday

PM stands for Post Meridian, which is Latin for: after midday

At 12 o'clock it is neither before midday nor after midday (midday stands for middle point, not really "day"). The proper terms for the two 12 o'clock hours are midnight and noon; then a second past either it is 12:00:01 AM or 12:00:01 PM, respectively.
I'll be darned, you're right. http://www.boulder.nist.gov/timefreq/general/misc.htm
 
  • #10
Noon and midnight aren't technically either one.
 
  • #11
Alright then, what is the proper greeting at midnight or noon? Should I avoid greetings at these times..I mean, "good midnight" just doesn't sound right, and "good nooner" could get a person into trouble.
 
  • #12
Ivan Seeking said:
Alright then, what is the proper greeting at midnight or noon? Should I avoid greetings at these times..I mean, "good midnight" just doesn't sound right, and "good nooner" could get a person into trouble.

Better than 'Good AM' and 'Good PM'
 
  • #13
Ivan Seeking said:
Alright then, what is the proper greeting at midnight or noon? Should I avoid greetings at these times..I mean, "good midnight" just doesn't sound right, and "good nooner" could get a person into trouble.

Well, the boundaries for day and night don't lie on midnight and noon. In fact, midnight and noon are the midpoints for day and night, so it should be extremely easy to decide a greeting at these times.

Alternately, you could scribble a word on a napkin without looking and see if it is day or night.
 
  • #14
Somehow I don't think you're all following the idea here...:biggrin:

Morning comes before noon, and afternoon come AFTER NOON; thus the paradox. :rolleyes:

Even worse, it was a joke. :rolleyes: :rolleyes: :rolleyes:

:biggrin:
 
  • #15
I'm feeling sick, so ignore my mumbling.
 
  • #16
Ivan Seeking said:
Alright then, what is the proper greeting at midnight or noon? Should I avoid greetings at these times..I mean, "good midnight" just doesn't sound right, and "good nooner" could get a person into trouble.
Words are unneccesary. Just extend a handful of frozen broccoli to the greet-ee and that should be sufficient.
 
  • #17
Gokul43201 said:
I'm feeling sick, so ignore my mumbling.

Don't feel bad, Hurkyl just threw me for a good one a few days ago. :biggrin:

I hate it when that happens! :eek:
 
  • #18
Wow MIH, is that really you?
 
  • #19
MID - eclectic

midnight is middle of the night. it is either one ~ you choose or snooze! once it gets to 11:59:60 it is technically midnight...AFTER that by one secono it is morning, altho it's considered night.

okay. i'll stick with calling it MID-Night-electric no matter what the video store says : )

i gave up believing what i read after reading a few paragraphs of that one book, i can't remember.

(!xck) :eek:
 
  • #20
Ivan Seeking said:
Wow MIH, is that really you?
That's me - down in Texas. yeehaw! :biggrin:
 
  • #21
Yeehaw! Hey there good lookin! :biggrin:

That's really my picture as well. It was a terrible rice picking accident...
 
  • #22
midge

MIH

nice picture. you're much prettier than barbie.

IVAN SOUGHT that isn't really you :devil:


(!xck)
 
  • #23
If it is exactly midnight and you have to decide whether to call it AM or PM, simply take a deep breath, letting a fraction of a second pass, then you can safely call it AM. Then ask for a 'nooner'.
 
  • #24
Ivan and ph, you are so sweet. :smile: Here - have some of this pecan pie I brought back from Texas. *Shoves slices of pie into the computer*
Trib, I would give you a piece of pie also, but I'm afraid you might get the idea to warm it up in the oven. :eek:

Hey - I just noticed - it's 12:00... (AM according to my PC)
 
  • #25
Ivan Seeking said:
Wow MIH, is that really you?
What at cutie, huh?
Nice hat, Math! :approve: Nice picture, too. :wink:
Can I have some of that pecan pie? :shy:
 
  • #26
MIH, you look absolutely beautiful! You are so cute in that hat! I look like a dork in hats. :frown:
 
  • #27
Thanks, Evo and Tsu. My baby sis and I thought it might be fun to take some pictures in our cowboy hats while I was down for a visit. :smile:
Here is some Texas pecan pie
*stuffs two large slices of pecan pie into computer* ...
just warmed up in the oven and...
*stuffs two giant scoops of Blue Bell vanilla ice cream into computer*
something to go on top!
 
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  • #28
Sorry that I never replied yet, its just that when I went to the logic section, there was a "-" on the replies table, so I though man, this is one dead forum, :rolleyes: Yes, I believe midnight is technecly not AM nor PM, but according to logic and computers (which has the final say), midnight is AM, the beginning of a new day, the sign was wrong, hehe. The sign just said that there was a deal from midnight new years eav, to 1:00 AM new years day, when technecly, it should have said that there was a deal from midnight new years day , to 1:00 AM new years day.

Problem solved :)
 
  • #29
I thought people put 12 midnight as 12 MN and noon as 12 N ? There is no PM or AM associated with 12 o clock right?
 
  • #30
Evo said:
MIH, you look absolutely beautiful! You are so cute in that hat! I look like a dork in hats. :frown:
Tsunami said:
What at cutie, huh?
Nice hat, Math! :approve: Nice picture, too. :wink:
Can I have some of that pecan pie? :shy:
ph said:
MIH

nice picture. you're much prettier than barbie.

IVAN SOUGHT that isn't really you :devil:


(!xck)
I'm lost... I don't see any picture, but I'm guessing its a picture of her with a cowboy hat on, in texas.
 
  • #31
It's gone now, Mk.
It was a limited time only thang!
(but your guess was correct)
 
  • #32
yes, midnght is AM.
 
  • #33
Math Is Hard said:
It's gone now, Mk.
It was a limited time only thang!
(but your guess was correct)
MIH, you tease! Your picture was a lot cuter than Barbie!
 
  • #34
It was fun for a while, but I missed my injection-molded look! :biggrin:
 
  • #35
What most of them said... Just like 1:00 and 1 second is the turning point from 12 to 1; so is 12:00 and 1 second is the turning point from PM to AM and vice versa.
 
  • #36
What most of them said... Just like 1:00 and 1 second is the turning point from 12 to 1; so is 12:00 and 1 second is the turning point from PM to AM and vice versa.

------ The world is a problem... SOLVE IT!
 
  • #37
Gamish said:
Sorry that I never replied yet, its just that when I went to the logic section, there was a "-" on the replies table, so I though man, this is one dead forum, :rolleyes: Yes, I believe midnight is technecly not AM nor PM, but according to logic and computers (which has the final say), midnight is AM, the beginning of a new day, the sign was wrong, hehe. The sign just said that there was a deal from midnight new years eav, to 1:00 AM new years day, when technecly, it should have said that there was a deal from midnight new years day , to 1:00 AM new years day.

Problem solved :)

Well, I guess it depends if they meant to have a 25 hour sale starting actually at midnight of New Year's Eve and running one hour into New Year's morning, or if they had a ONE hour sale from midnight to 1 AM on New Year's morning (what a lame time for a sale if that's really what they meant...I can hear the managers at the staff meeting for that one: "Yep, we're going to have a sale, during the one hour we're guaranteed nobody is going to be out buying videos." I feel bad for the poor schmuck who had to work that night because there was a sale so they couldn't just close early when there were no customers.)
 
  • #38
Monique said:
midnight is 00:00 hours, thus AM :rollseyes:


but technically 00:00 on the 25th December is equivalent to 24:00 on the 24th December.. :rolleyes:

But you never see 24:01 on a clock? Or 24:00 for that matter.

After 24 hours you must start a new day.
 
  • #39
12:00AM= Midnight. As French is, Minuit. Mid-day is Midi.
 
  • #40
Post Meridian and Ante Meridian is only used in USA rest of the World uses 24 hour time, so..midnight is 00:00 hr.
 
  • #41
I think this thread should be retitled: Semantics

Why? Because that's what we're really arguing.

Noon and midnight are completely arbitrary times that we humans created to satiate our anal retentive need to clearly define when one day ended and another day began. Although noon and midnight loosely correspond to the sun being at it's highest and lowest points relative to the observer, this 'time' changes daily.

However, the common usage in the US is for 12 AM to be the start of a day and 12 PM to be noon on that day.

Thus, your sale that started at 12 AM on New Year's Even and ended at 1 AM on New Year's Day was indeed a 25 hour sale... although the language can be quite confusing...

When, oh when, will the US switch to the 00:00 to 23:59 time system?

Cheers...
 
  • #42
tumor said:
Post Meridian and Ante Meridian is only used in USA rest of the World uses 24 hour time, so..midnight is 00:00 hr.

24 hour time is much easier. I use it in the lab, and sometimes forget to not use it outside the lab, which confuses people. Since I have done experiments that have run 24 hours or longer, and have required helpers at noon and midnight, just to be 100% certain there was no confusion, I just put a note next to the clock time that says "midnight" or "noon" where appropriate. The only other time life gets confusing is when one of those overnight experiments is running the night the clocks change from daylight savings time to standard time or back again. I really wish daylight savings time could be banished. Then I end up having to explain to the lab that the lab is going to live in a time warp until the experiment is done. It's even more fun in the animal facility trying to explain to a group of technicians (people basically paid to clean cages for a living) that the animals don't care about daylight savings time, but they will care about their lights suddenly going on or off an hour later or earlier if the technicians run around changing the clocks timing the light schedule.

So, yep, I'd love to see everyone switch to 24 hour time and do away with daylight savings time.
 
  • #43
Have them change the sign to:
We open at lim[x -> 00:00+](X AM)
 
  • #44
This question is sort of like that question in the year 2000..."Is 2000 the start of the new millenia, or the end?" To answer that question, the whole 2000 calendar year was still in the 20th century. The year 2001 was the beginning of the new century and millenium. I believe the first year was 1 A.D. and not 0 A.D. Time, however starts at 0, and therefore the new day starts at 0, that is 12:00 AM.
 
  • #45
Technically, you can write 12:00 M for noon, and 12:00AM or 12:00PM for midnight since midnight is both before and adfter noon.
 
  • #46
Is the average time on Earth 0:00 or 12:00?
 
  • #47
Moonbear said:
I really wish daylight savings time could be banished.

I know a chemist who refuses to use daylight savings time, not only in the lab but for everything in his life. He prohibits his family from changing the clocks in their house from GMT. He's very, very strange, and has a big white beard. He drives a Volvo with moss growing on its roof. I think one day he's going to live on the top of a cliff in a little white shed with only a snail for company, and only toast for sustenance.
 
  • #48
brewnog said:
I know a chemist who refuses to use daylight savings time, not only in the lab but for everything in his life. He prohibits his family from changing the clocks in their house from GMT. He's very, very strange, and has a big white beard. He drives a Volvo with moss growing on its roof. I think one day he's going to live on the top of a cliff in a little white shed with only a snail for company, and only toast for sustenance.

I've known more than a few "eccentric" chemists. I think it's all those toxic chemicals they play with. :eek:
 
  • #49
but is actually a physicist who wants to change the calendar. I'm a chemist and I think physicists are more strange...lol

http://www.newscientist.com/article.ns?id=dn6835
 
  • #50
ConcealedDreamer said:
12:00AM= Midnight. As French is, Minuit. Mid-day is Midi.

Heck, this sounds unlogical to me, 0:00AM should be midnight and non-existent 12:00AM=0:00PM=midi.
Lucky me I don't live in the states, that's for sure! Long live 0:00-lim_{t->24:00}(t) (No offense to the latin language though :wink: )
 

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