AM & PM decoded 🕒 It’s all about the meridian!

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[@asbjrntverberg2428]

I don't get that meridian stuff. It goes over my head. 🤷

[@umeanduo]

😂😂😂😂😂

[@craigsuber208]

Well played, my man. Well played.👏🏿👏🏿

[@ramunasstulga8264]

Mfs be like at math "teacher's fault" 💀

[@GunDinFight]

😂😂😂

[@blueskyla7978]

Plot twist. OP is serious. 😂

[@topsadda]

I can't believe me, from a remote country in East Africa-Uganda actually learnt this in my dusty primary school! Go Uganda!

[@Gluffy-G]

For real dude! South African here - I knew this in sub-b which is now Grade 2😅

[@ChestyStClair]

Same in France. You learn this in primary school...

[@seanin1990]

I was in Nairobi and Zanzibar. It surprised me that the guys there I spoke to didn't acknowledge Zodiac signs or knew what constellations were. Then I realized we lived on a big planet with many cultural differences.

[@MrKrytikol]

Not all Americans are dumb. Unfortunately intelligence isn’t prioritized here, and the smart ones get picked on.

[@charlesk7182]

I was born in Uganda 🇺🇬 as well and likewise I learnt this stuff in primary school in Uganda 🇺🇬! Wow! Hats 🎩 off to all those dedicated teachers who gave us some important Geography lessons

[@vinceprice4089]

I always learn something from these guys. Love their podcast.

[@AwesomeBlackDude]

Weeeell not everything and as I discover this platform won't allow you go behind the curtain. 😬

[@kapp651]

​@@AwesomeBlackDudealways a strange hater

[@BqgWyy]

I'm in my 40s and I'm a very curious person into all kinds of trivia, history, astronomy. I read Wikipedia for fun when I'm drunk. And i cannot BELIEVE that 1) I never KNEW this, something so BASIC 2) I NEVER EVEN WONDERED ABOUT IT! I've just been saying am and pm my whole life. And it's not amplitude modulation lol

[@theresamiles2443]

@@BqgWyy. I will be 70 on 11/11 and I’m just learning what the am and pm mean 😮….. i am just as curious, when I’m watching or reading something I don’t know I’ll write the name down and look it up.

[@BqgWyy]

@@theresamiles2443 It's crazy isn't it. Why didn't we ever look into this

[@johnpaulnwafor6251]

Neil deGrasse makes things beautifully simple.

[@mikekelly5869]

From what I see in this comments section, that's jyst as well.🙄

[@matthewozga]

boys playing in girls sports...

[@williamroberts6803]

Actually he’s wrong a lot of the time. He knows certain things well but doesn’t know a lot of things we know.

[@eeeee11235]

I was like "so THAT'S why you can determine north & south from your watch"

[@cbwavy]

Finally understanding AM and PM is so satisfying. Thank you for this.

[@ilichramirezsanchez5996]

if you are over 25 and you didn't know this, you should be ashamed... it really goes to show me that Americans are really dumb...

[@christoph7510]

It could have been a quick google search

[@helloxonsfan]

*I actually like the names "After Midnight" & "Pre-Midnight" better...!!!* (lol) 👍🏽 🤣

[@omodiagbedominicedeoghon4607]

😂 You mean there are educated pt who don't know the full form of a.m. and p.m.?

[@diegoe.jimenezdelgado.3986]

Before in Spanish is "antes", in Latin: ante... that's why it's easier to understand for us. The meridian is over the place you are, your country or State, that's why its over your head, the Sun goes from East to West along the day.. The first meridian is in Greenwich, Scotland, because of an agreement..

[@robinradman549]

I'm learning so much from these shorts with Neil. And I'm 62 years old. Never stop learning!

[@ParvaizRaja]

Me too. BTW, I'm also 62.

[@Grump-hi2pb]

@@ParvaizRaja Hey! I'm 74, and you guys got some catching up to do! Keep enjoying the ride! It just gets better and better

[@DIOSEPHBORG]

Learn is the best pleasure ever. Probably a eternal one.

[@pocapaypay]

This man just teaches me something new every time I watch him. His kids are so lucky.

[@fergsterw1969]

It never ceases to amaze me what kids are NOT learning in school anymore!

[@joshuaburski5776]

Kinda like they are restricting knowledge😮

[@runix21]

I was thinking that I learned this in Elementary school 😂 I was more surprised I remembered that

[@des7334]

How old are you

[@runix21]

@des7334 44 so it's been a long while

[@ChrisKsan]

Maybe in 'Murikah, but in many other countries, stuff like this is basic general knowledge and it's spelled out "Ante-Meridian / Post-Meridian" in Geography class when the Atlas or world map is presented to kids in preparation for teaching them about world Geography.

[@marcmayhem0412]

Chuck is kinda correct. AM does begin after midnight.

[@FrankGreening-Morash]

Half right half wrong

[@FrankGreening-Morash]

Yin yang

[@visionsofpromise]

​@@FrankGreening-Morash same same

[@mnw1871]

That's how I remembered it when I was a little kid. (AM = after midnight and PM = "Pefore" midnight) .

[@henripoincare77]

​@@mnw1871Pefore😂😂

[@LordCK_DC]

I love their setup because you have one guy that's highly educated on the topics and then you have another person that learning the info just like I am while watching. So when the professional explains stuff he gives great details and examples that I'm sure he wouldn't give if the other guy wasn't apart of the show

[@SPCJTT]

My aunt shipped a package from Japan to America, and it arrived the day before it was sent. 😂😮

[@sterlingcampbell4394]

I was stationed out there. It's a 13 hour flight from Cali so you get there the next day. It's weird flying back cause you lose an entire day. Mean case of jet lag. 🤣🤣

[@888_Crypto]

Time travel right there.. 😂

[@raycrawford2374]

Time is relative

[@_G_H_0_S_T]

when I was a kid, I was convinced one could travel back in time by just constantly crossing time zones backwards xD xD xD

[@mikeagbenya8418]

​@@_G_H_0_S_T💀💀💀

[@חנהגלפנד]

I am 61, and that's the first time I hear that explanation. Thank you so much for sharing knowledge 🙏

[@ironyman42]

Exactly the same with me ... 61, learned it just now.....😊

[@sharonadetunji_Onile]

😮😮😮😮😮

[@AngelEdwards-dc2np]

I started cracking up when he said he thought A.M. meant after midnight cause I thought the same thing LOL 💀🤣😭

[@saibot2957]

P.m. pefore midnight

[@danielarthurcxit6544]

Mee too😂

[@AngelEdwards-dc2np]

@@saibot2957yoooo I’m cryiiinggg 💀🤣😭🤣😭

[@hemmper]

after midnight, preceding midnight, if it helps you remember it's not wrong!

[@eddyram4932]

I knew about the ante meridian, but the “after midnight” is not a bad assumption, and PM could be “past midday”😂

[@pandoraelysium]

At morning / past morning. 😂

[@farfromirrational948]

Apparently meridian translates to mid-day, so past mid-day is precisely what pm means

[@Orchideology]

I actually learned - and thought until now - that am was 'after midnight' and pm 'past midday'.

[@nickboon1235]

Chuck is every one of us😂

[@markphc99]

you're American I'm guessing

[@Enixious99]

​@@markphc99You're *insert country origin* I'm guessing? Your people must be born knowing everything.

[@markphc99]

@@Enixious99 no , just a decent education system

[@algee6245]

You mean kindergardeners?

[@jacobmarley2417]

Love the commenters slamming Chuck who obviously dont listen to Spacetalk on a regular basis. He is by no means an average american or dumb. He is actually very intelligent.

[@sfgeoffrey]

Thank you! I love learning something new...

[@pooryorick831]

Actually, it is ante meridiem and post meridiem. Because objects of a preposition take a different case in Latin, which is where the the terms come from.

[@6431Pyros]

and a plus to your info is that "meridiem" means "noon" so "before noon" and after ;)

[@demetrrius3000]

Not trying to be funny, but is that not what he said? Without reading the subtitles which I’m assuming are wrong, you would have thought that’s exactly what he said

[@ShawnNac]

​​@@demetrrius3000Neil said it was ante meridian and post meridian. But it is ante meridiem, which is Latin for "before midday" and post meridiem is the Latin "after midday."

[@archiehannibal3469]

​@@ShawnNacwhat's exactly your point, because you're saying the same thing he said.

[@locqueenMD1]

It ends with a "m", not a "n". Meridiem, not meridian.

[@happymethehappyone8300]

As a child to help myself remember the difference,, I would think A.M. = After Midnight & P.M. = Pefore (Before) Midnight..It makes me laugh now,, But it worked.

[@ibrahimbabangida6016]

That's funny. I remember pronouncing Guinness as GUYNESS

[@Lin6055m]

Cute bridge

[@andrewahern3730]

Amplitude Modulation. Oh, wait, wrong AM.

[@user-xb3my6zw6r]

HeHe!

[@scamster71]

So P.M. is Phrequency Modulation?🤣

[@Lethargic_Logician]

​@@scamster71 there is actually a PM in communication engineering: Phase Modulation

[@jlaufangyt]

PM. Is putz meridian...

[@scamster71]

@@Lethargic_Logician Ok, now I feel dumb for not thinking of that.

[@GregoryMahn]

I was taught, in school back in the early 70s, that AM is after midnight and PM was pre-midnight. Hearing this explanation is new to me.

[@mannyperez1880]

Meridian actually just the latin word for midday. 'Meri' being half and 'dian' coming from 'dias' or day. Same root for circadian which translates to "close to a day"

[@EBiz-tv9jq]

Shut up noone asked.

[@utubesuxalotofazz]

But it's not. It's the definition of a line going directly north and south from a person's perspective. It might have been a term for midday, but it has been utilized by a group of people who don't speak Latin for another purpose. It's original meaning is useless to 99.99% of the world

[@StateGenesys]

Okay? That explains nothing.

[@Liz.CottageCore]

Doesn’t am stand for anno domini or smth like that

[@thomasspann8678]

It's amazing when you learn something you really don't need to know. Now I have to use it in a sentence. I'm going to impress somebody with my newfound intelligence.

[@alphaquinon1688]

When I'm in middle school, on an english lesson, I learned that AM is After Midnight and PM is Post to Midnight (toward the midnight) 😂

[@dvldog_]

And Neal will tell you all that order just happened by chance. All those laws of nature and physics just happenend out of the blue. Amazing...

[@tradersquarter]

@dvldog_ Yes, over millions and millions of years, boys and girls, through "Natural Selection"....and we call that "science".

[@darylingoteborg3178]

What’s your point? If this is an attempt to make even this about religion then accept you’re obsessed

[@normancameron727]

That part is crap because there is thrre things that that exist and has a cause and effect on everything else . Time , Power And Space And they are ALL INFINITE .

[@rayokasali]

I love when information doesn't just talk about the what but also the how and why. Context beautifies stories.

[@Melora-cx7if]

Doesn’t it feel good when you KNEW it already, lol

[@stephenlitten1789]

I feel so smart. Time for a drink and to feel dumb

[@Melora-cx7if]

@@stephenlitten1789 I gotta wait till tomorrow to do that. Drink one for me!😉

[@stephenlitten1789]

@@Melora-cx7if 👍

[@jackwhitbread4583]

No, it actually feels better when you learn something you didn't already know. It's why scientists become scientists, because you never stop learning about the world amd universe.

[@BqgWyy]

I can't believe i didn't know this. It's so basic. I never even LOOKED into it or wondered why we say am pm. How weird

[@michaelmashburn6068]

Amazingly short, simple and to the point. I learned something new in seconds

[@chrisjacob2716]

Every time I watch this guy I learn something

[@mikekelly5869]

Try getting some actual education. It will blow your mind.

[@Sunluvr1]

I’ve understood the concept of AM & PM over 50 years but never once thought about what the abbreviation stands for . I can’t believe that !!!

[@KristenRowenPliske]

Well, Chuck, you’re not wrong. AM is after midnight. 😄

[@TREVINparty]

I thought it meant that too

[@andrewtol8756]

Well, he was wrong, because he said AM is short for After Midnight, which it is not.

[@MrT------5743]

Technically pm is also after midnight. Just not immediately after. Since it cycles am and pm are both after and before midnight. Duh

[@g.m.3473]

And PM is pre-midnight

[@duexxatuxx]

In greek we have a cool word called "midday" which is around 12pm. We also use little words like "before midday" and "after midday" π.μ. μ.μ.

[@hiramlewis3873]

Honestly I never look at the meaning of AM and PM. Until today I thought AM meant At Morning and PM was Passed Morning. I just learned something today or since it's past Midnight, it's tonight....

[@gavinsheppard7772]

It's At morning and Past morning 😢

[@solairegwyn8761]

Its amazing how old clock and navigational science terms are still being used to this day and how it just turned into acronyms.

[@philipholbrook7461]

I really dislike am/pm. I prefer 24 hour clock.

[@JusNoBS420]

Military background by any chance?

[@RandomNPC001]

@@JusNoBS420 A lot of countries use 24 hour clocks. I`m from Brazil and we are taught to use 24 hour clocks from the start.

[@philipholbrook7461]

@@JusNoBS420 20 years

[@PainSled]

Yeah, I find the 24hr clock much easier to parse. Especially the fact that the 12hr clock goes: 10am -> 11am -> 12pm -> 1pm That 12pm comes before 11pm is easy to forget when you're tired, or in a hurry

[@williamhrivnak7345]

@@JusNoBS420 Hospitals in the US use it too. It prevents errors with the timing of meds/interventions when every hour has a unique number. And it makes math easier. If I give a med at 6 and the next is due in 8 hours thats hour 14, I don’t have to reset over the AM/PM line

[@Somali.Pirate1]

Well growing up in the UK we were taught as children "At morning" and "past morning".

[@eeeee11235]

so THAT'S why you can determine north & south from your watch. wow thats pretty cool

[@mikeottersole]

After midnight and pre midnight. Makes perfect sense, Chuck.

[@DavidWilliams-oq4up]

I guess he didn't make it as a comedian.

[@Benwut]

Ante has to be my favourite latin prefix and idk why. Antebellum, Ante Meridiem, Antechoir, Antechamber, the list goes on

[@scottgray4623]

Now if we can just get rid of Daylight Saving Time, high noon would actually occur at 12:00 PM ... at least a couple times a year. 😕

[@MrT------5743]

It already does a couple times per year. Duh

[@jacobmarley2417]

daylight savings has absolutely no impact on anything anymore. It is a complete waste of public energy and needs to go away with the imperial measurement system

[@backtothefuture2880]

OK, after ten listens it finally sank in 😅. You can tell school wasn't my biggest achievement 😂

[@usuariocelular8065]

In spanish i thought: A.M :Antes de la Mañana P.M : Pasado la Mañana. 😂

[@WintersChildd]

Him: what does AM stand for? Me: After Meridian! Oh wait... 🤣🤦‍♀️

[@sega-re-trop-vieux]

Who needs AM and PM when 24h has … 24 hours !!! Be smart and use the European way, 14h00 and 02h00 … we know which one is morning and afternoon without any weird letters behind it. I won’t even talk about feet, inch and miles because it is the same

[@Hinatachan360]

I learned this way back in military school. Cool that Niel is sharing this lesson. Everybody doesn't know this.

[@Diyn58]

I assumed AM was After Midnight and PM Post Morning ahahah

[@helenstokoe459]

So pleased I've seen this, I have never wondered what AM and PM stood for. Thank you. 🙂

[@kenroberts5768]

But the endpoints always confuse me… Is noon am or pm⁉️ Is midnight am or pm❓🤷‍♂️ Now I gotta look it up again😢❗️

[@tenadefiant]

Noon starts PM and Midnight starts AM

[@elektron2kim666]

A.M. is 00:00:00+. P.M. is after/= noon, evening, bed time, sleep. 4:30 A.M. is early.

[@emmanuelernest7185]

I think to understand this you have to devide the circumference into quarters so am starts at midnight but you won't see the sun till it finishes the first quarter 😅

[@5e88e]

00 - 24. So no need for some am and pm. Easy

[@gomezgomezian3236]

@@5e88e Yeah, but 'Mericans! don't understand 24 hour clock. So it's AM - PM for them.

[@cydkriletich6538]

Guess this is why High Noon is when the sun is highest over our heads. I love this guy; he makes me know there’s something cool to learn every day, and glad of it!

[@bland9876]

And the whole thing is dumb 24HR for the win.

[@wor1dconquerer170]

L

[@protercool8474]

L

[@JordanODash]

I didn't think it's that difficult infact 24 hrs clock meant unnecessary maths for kids We learnt both ways but watches and clocks ran on 12 hrs

[@masthanvalisayyad427]

The most brilliant man on earth. Take any thing from anywhere and he will have his answer. Brilliant!

[@Nedubov]

More precisely - meridiem. Not meridian.

[@AK-ek8vf]

Neil is like a saint who like common people than a scholar.Neil enjoys a talk and explain every detail with joy no dissatisfaction or judgement.

[@MissNikolite]

Learned something new today! I love watching these shorts ❤

[@lanobaby9569]

I so understand now;....... Genuinely;Thank Mr. Tyson.You have broadened my intellect in so many ways ☝🏾🧐

[@jamalkareem958]

So pleasing to watch

[@expeditenow3664]

Good info... The way he started.... Excellent teacher

[@schattensonner]

"After midnight" "Past midday" was always my quickfire way of remembering how you tell the time overseas.. I knew the ante/post meridian but somehow the "easy english" variants were the first to come to mind for way to long..

[@4real4real-cf1ii]

He took bro back to school real quick 😂😂😂

[@BOT_JERRY]

That giggle after the after midnight joke was so genuine.

[@SlinkyJosh]

Why did I never wonder in all my 33 years what AM and PM stood for?!

[@vashtivalentino6913]

Hey Mr the concept of North & South is understood by most folks is the word used b4 each necessary, also thanks for the meridian explanation of am /pm

[@UmarKhan-ku8qe]

I always learned new things here with logic and explanation 👏👏👏

[@eurooceania5562]

Dude was like, "I thought my dad was my mother's wife."😅

[@CoraZa1131]

We were taught this, as kids in El Salvador. "Ante Meridiano" y "Pasado Meridiano" 😊

[@stevelecours4472]

In french AM fits for Avant Midi (before noon). aPrès Midi for PM (after noon)

[@paulobi4928]

Explanation made easy. Great.

[@SilverAegis39]

I am french, and always though A.M. stood for "Avant Midi" and since "Après Midi" starts with A too, we use the next letter, being the P. I also had that thought when i was 10 and didnt know Am and Pm was in every languages, then never bothered thinking about it again.

[@lyndacrossley9548]

Thank you. Sure we learnt this in school, but with time we forget.

[@rodneybryant6543]

What a wonderful way to learn.

[@ronniewilkerson2027]

I have always asked the question as to AM, PM, but no one was ever able to answer it. Thanks.

[@Smilemaker4u]

Thank you for the education sir! ❤

[@beckyriley2674]

I love it when he talks to Chuck, they are hilarious together.

[@Pscotti808]

'This term, in turn, is derived from 'meridies', meaning 'midday' or 'south'. Hence, the Sun at its meridian signifies the time of day when the Sun is at its peak, marking the middle of the day-a transition point calling for a restful interlude. Is this if we get lost? After midnight sounded right!

[@RivetHead999]

I used to think it meant “ante median/post median” which means middle/center. Made that connection after learning direction/relation in biology. Guess I wasn’t too far off, but this makes more sense.

[@gilberturias5636]

Badass, how Neil let's him answer first, Post Meridian and right after Neil shouts it out "Post Meridian" Most of us, including me, will sometimes give answer just as the person we are asking question to is going to answer lol.

[@paulfroese1469]

Now I know. Always wondered and no one could actually explain that. Thank you Neil!! 😅😊

[@chairrider2462]

AM is amplitude modulation and FM is frequency modulation. Don't know about that PM stuff. In the navy it was Preventive Maintenance

[@Fredfredfredfredfredfredfred]

I’m awestruck at the poetry of everyone having their own meridian line

[@bigbabygt94]

Thanks for the pickup line

[@mildredcordero4949]

I have old parents. My Dad would say "3 post meridian" sometimes. It was cool for me to get that right in class.

[@duece444]

I can listen to this stuff for hours

[@Kayessee]

I remember learning what am and pm meant when I was in 3rd grade... My school was awesome.

[@sandrahayden3708]

Learn something new everyday. Thank You Sir.💙💙

[@mekile616_]

This is one of the first things we learned, Learning to Navigate by Sextant, recording and plotting courses, All you need to get your bearings is one direction if you can identify the North Star or the southern Cross, your able to know all directions, all that's required is clear sky's.

[@Dr.Kryptanical]

"Nothing goes over my head... I am too fast, I will catch it!"

[@aricliljegren890]

That also explains the term "high noon" since that is the moment between am and pm when the sun is directly above you.

[@paulnagy8551]

Nobody's ever told me about the meridian that we all individually have. It makes understanding AMPM so much easier. I used the trick that that gentleman used after midnight if pefor midnight but obviously that's not the proper way

[@brucebwondema7347]

Our AM is from sunrise to sunset and sunset to sunrise is PM 6 - 6 am and is called 1am to 12am 7pm to 6am is called again 1pm to 12am. This is in Ethiopia - Tropics.

[@jeannek.srensen856]

We do not learn this at scool in Denmark until we start taking English lesson around age 7 - because we don't use AM and PM ...one minute before midnight is 23.59 for us 😊

[@emissaryyarbuckle702]

Thanks

[@theeddytor3490]

you learn something new everyday then.... this was nice

[@annpitcher2890]

Thank you for your informative knowledge.

[@TheWorld_2099]

Finally…! Perfectly explained so I know what it really means, and why it means that.

[@archangel5972]

I asked my third grade teacher what am and pm meant. She smiled and said something like “you’ll never remember this, but they mean ante meridiem and post meridiem”. I never forgot :)

[@octavioalatorre8957]

This is another 1 of those , you do learn something everyday. GIGO moment.

[@fredrikandersson1846]

I love how Neil interrupts him amd yell POST-meridian like he dropped a punchline😂

[@josemorales2624]

I'm from Chile and always thought that a.m. stands for "Antes del Mediodía" (before noon) and p.m. "Pasado Mediodía" (after noon)

[@MrGigaHurtz]

Lololol Chucks After Midnight/Pre Midnight actually makes a lot of sense too haha

[@roberthein2156]

Neil is so interesting, 🧐 always giving us information. That…… well….. I’ll never use . But will never remember ? Thank-you again .

[@ewaf88]

One of the great unknowns of my life, has now been explained. Thanks guys.

[@dingaroo2003]

I learn something new everyday from him!