Who Came Up With Days, Hours, Minutes and Seconds?
ฝัง
- เผยแพร่เมื่อ 25 ธ.ค. 2024
- Episode 1 of 4
Check us out on iTunes! testtube.com/po...
Please Subscribe! testu.be/1FjtHn5
We've all learned it takes 24 hours for the Earth to rotate once on its axis but that isn't the whole story at all. We have come a long way over the course of human civilization.
+ + + + + + +
Previous Series:
Why The Gemini Space Program Revolutionized Space Travel: www.seeker.com/...
+ + + + + + +
Sources:
Why Does The Earth Spin?:
www.universetod...
“In a classic episode of this video series, I did the calculations for how fast the Earth is spinning. We know the Earth is rotating, but why? Why is it spinning?"
The First Point of Aries:
astronavigatio...
“In astronomy, we need a celestial coordinate system for fixing the positions of all celestial bodies in the celestial sphere."
How Long Is A Day? How Long Does It Take The Earth To Spin Once On Its Axis?:
plus.maths.org...
“It might seem obvious that the answer to both these questions is 24 hours. But the correct answer is not quite so straight forward. The Earth's axis always points in the same direction relative to the distant stars, at least to a good approximation."
9 Things You May Not Know About the Ancient Sumerians:
www.history.com...
“Sometime around 4000 B.C., ancient Sumerian culture emerged on a sun-scorched floodplain along the Tigris and Euphrates rivers in what is now southern Iraq."
Sumer:
www.britannica....
“Sumer, site of the earliest known civilization, located in the southernmost part of Mesopotamia between the Tigris and Euphrates rivers, in the area that later became Babylonia and is now southern Iraq from around Baghdad to the Persian Gulf."
Why Are There 24 Hours In A Day?:
www.abc.net.au/...
“While each country has (in broad terms) historically had distinct measurements for distance, weights etc the method of splitting the day into 24 hours, one hour into 60 mins and one minute into 60 seconds seems to be the only one in use, and indeed to me the only one I know of. "
Keeping Time: Why 60 Minutes?:
www.livescience...
“How did we come to divide the hour into 60 minutes and the minute into 60 seconds? These smaller divisions of time have been in practical use for only about 400 years, but they were vital to the advent of modern science."
Why Is A Minute Divided Into 60 Seconds, An Hour Into 60 Minutes, Yet There Are Only 24 Hours In A Day?:
www.scientifica...
“In today's world, the most widely used numeral system is decimal (base 10), a system that probably originated because it made it easy for humans to count using their fingers."
+ + + + + + +
DNews Plus is built for enthusiastic science fans seeking out comprehensive conversations on the geeky topics they love. Host Trace Dominguez digs beyond the usual scope to deliver details, developments and opinions on advanced topics like AI, string theory and Mars exploration. DNews Plus is also offered as an audio podcast on iTunes.
+ + + + + + +
Trace Dominguez on Twitter / tracedominguez
DNews on Facebook / discoverynews
DNews on Twitter / dnews
+ + + + + + +
how can you know that the earth rotates counter clockwise? which way is up/forward in the universe lol.
or is that if you have a birds eye view of the rotational axis (in the northern hemisphere?) I assume?
Reference frames ftw!
Sometimes I like to think that we're all spinning upside down. It's just an arbitrary designation someone made along time ago, like the symbols we call numbers and letters and the lengths we call meters or feet or the names we give to animals and plants or even all the other objects around us. Even the concepts or ideas we haven't had yet either because they're non-corporeal or simply because we haven't seen them yet have semi-random names too (it's order built on-top of randomness).
@Faqyur Ma'ama
And it also matters what you call clockwise - if it is the direction the hands move on an analogue clock, then when looking towards the front on one of my clocks it is to the left (also how do you define left - the direction of a positive increase (as defined in maths) in the shortest angle between two digits?) and the rest of my analogue clocks all go anticlockwise!
@@vegantubers5585
Yes you can, but you would need to be careful about what feature of that body you use . The ancient Egyptians used Sirius (the Dog Star) to define their New Year's Day - the first day of Thoth.
Depending for what you want to measure the passing of days it would be useful or not.
The Jewish calendar inserts extra (lunar) months every 2 or 3 years so that the months stay roughly in line with the sun. This means it can be used by farmers to know when to sow seed and reap the harvest.
The Islamic calendar doesn't so Ramadan can appear at any time during the solar year meaning the hours of fasting are longer or shorter (in the UK, for example, this difference can be quite stark, but in countries nearer the equator, eg Mali, the difference is not so marked) depending upon how the lunar calendat matches to the solar calendar.
"10 hours for day, 10 hours for night, 1 hour each for dawn and dusk." That adds up to 22, not 24.
Well spotted.
Thats exactly what I was gonna say :)
Jim Fortune true
That confused me too cause another video aid 12 hrs a night
Perhaps two hours were allocated for dawn and dusk, where one hour for dawn was the end of the night shift, then the next hour started the day... And at dusk, one hour was designated to end the day shift, then the next hour started the night shift.
Just a guess...
The French accepted GMT in exchange for the British accepting the metric system... Thus the saying "the English are going metric but they are going inch, by inch" :-)
Theres 13 months n a yr u cood even say 14 cuz on few days after 13 like 7 or 8 days
Actually there was a time conference or, international median conference in 1884. It established the time zones and the meridian of Greenwich was recognized. Before that, the zero meridian used was either in Paris, London, Madrid, Lisboa or Amsterdam, depending from which naval nation you came.
24 hours in a day, 24 beer in a case, coincidence,? I think not.
😂
Ha!
Kinda wrong on some points. "Sidereal" is pronounced as four syllables like "sy-DEE-ree-ul" in English and comes from the Latin _sidereus_ meaning "starry," from _sidus_ (pronounced SEE-duhs, stem _sider-_), meaning "star" or "heavenly body."
It is also _not_ the case that Egyptians used a duodecimal system. In fact, they didn't use a positional number system at all. The common division into twelfths is usually attributed to the Babylonians, like the sexigesimal system.
As for "minute" and "second," nobody actually knows why these divisions were chosen for timekeeping, but their etymology is clear. "Minute" comes from the Latin _pars minuta prima_ meaning "first small part" (from which the name for the "prime" symbol ′ came, used to represent minutes, arcminutes, feet, first derivatives, etc.) while "second" comes from the Latin _pars minuta secunda_ meaning "second small part" (though the symbol ″ is confusingly called the "double prime," used for seconds, arcseconds, inches, second derivatives, etc.). These phrases, divisions, and symbols were used as long ago as 1267 by Roger Bacon, who also defined "thirds" and "fourths" similarly, though obviously there was no practical way to measure such brief intervals.
Oh good, i thought i'd been saying it wrong in my head.
is "ree-ul" in sidereal pronounced REAL with a long eeeeeee?
Arramu Maiam It depends how you pronounce "real."
You can find a typical American English pronunciation for "sidereal" here: media.merriam-webster.com/audio/prons/en/us/mp3/s/sidere01.mp3 and a typical English English pronunciation here: www.oxforddictionaries.com/us/media/english/uk_pron/s/sid/sider/sidereal__gb_1_8.mp3.
So cool, I was curious how the second was quantified and you touched on that right at the end. I'd love to hear more about that topic all in it's own video.
What's before a second?
12 is a much more useful than 10 for fractions. 12 has 6 factors: 1, 2, 3, 4, 6, 12 compared to 10's 4: 1, 2, 5, 10 ; which means if you want to subdivide something you get more whole number results with 12.
12 is also very useful for building. If you have a string 12 units long in a loop you can make it into a triangle with whole length sides of 3, 4 and 5 - which form a right angled triangle.
Note also that 60 = 12×5 so it has 12 factors.
Not a lot of people realise that time (within a day) is just a sexagesimal (base 60) representation of the number of seconds since midnight (on a 24 hour clock) - in base 60 each digit can hold a value between 0 and 59 (in base 10), and so that we don't misread the digits (is 123 in base 60 supposed to be 1 23 or 12 3) we put a colon between each sexagesimal digit (1:23 is clearly different from 12:3). Then we call the units place value column (the 60^0 column) seconds, the next place value column left (the 60^1 column) minutes and the next plave value column left (the 60^2 column) hours.
I can't believe I graduated from so many schools including uni without learning about this.
You know, this guy is a genius. He's created a channel by reading interesting information off of a laptop, and gets hundreds of thousands of subs because he's GOOD at it. Genius.
Just looked down at my hand and started counting my joints....... that actually makes a hell of a lot of sense to count like that
Hard to write all that on a napkin at a pub quiz
Good general description, but the extrapolation from the number of finger joints to a 24 hour day seems so unlikely. The more probably route of 24 hours is found in simple geometry:
To create a horizontal sundial:
1) Draw two lines intersecting at right angles (East-West and North-South);
2) Bisect those prime coordinate lines each way such that you have 4 lines intersecting at the origin (at 45 degrees);
3) Set your compasses (dividers) to the desired radius and describe a circle from the origin intersecting all 4 of the lines at a total of 8 points;
4) From each of those 8 intersection points, and using the same radius, draw arcs intersecting the circle in 2 locations each, for a total of 24 intersections defining 24 exactly equal hourly segments;
Note: All of that is a 10-15 minute exercise in grade 8 geometry using only a compasses and straight edge and is independent of the notion that a circle should be divided into 360 parts called degrees.
5) From the origin erect a gnomon pointed at the pole star (southern cross);
6) From the sun's shadow read (about) 12 equal hours in daylight; and,
7) By sighting to any visible planet, star or the moon read (about) 12 equal hours of nighttime.
Note: In the northern hemisphere the shadow traverses "clockwise", hence that term, in the southern hemisphere of course the shadow traverses counter-clockwise. One therefore wonders, had civilization developed more quickly in the southern hemisphere, would not our terminology have been reversed?
Greenwich Mean Time - hmmm - not a complete description, but perhaps you didn't intent it to be. Greenwich Time was established in 1675 to be a regular mechanically accurate depiction of the "24 hour day" based on the earth's average apparent rotation with respect to the sun (about 4 minutes longer than a sidereal day). Greenwich Mean Time was set such that GMT noon was the average moment in time at which the sun would be due south of Greenwich. However the solar day is slightly irregular such that some days (high noon to high noon on the sundial) differ slightly form others, this irregularity is due to the tilted axis and elliptical orbit of the earth. The result being that noon on the sundial is about correct to GMT at the winter solstice and again on 3 other days of the year, but the sundial appears to lag behind GMT in mid February and lead GMT at the end of October, by as much as 16 1/2 minutes!
For a detailed description search for the "equation of time".
GMT has now been replaced with Universal Coordinated Time, referred to as either UTC or "Zulu", but effectively it has the same meaning.
If we use 24 hours a day when it is actually 23:56, does that mean we will somehow end up moving slower ...e. g. We lose 4 mins every day so in 60 days it will be 240 mins... 4 hours... So what we think as 5 in the morning might actually be 9... But it never happend... Why? Is it coz they already set the counter to work in 24 hours in the speed of 23:56? Or there is a hidden answer?
"Sidereal" has been pronounced as "si-deer-ee-al" according to astronomers I've spoken with. I've also read that the Sumerians were responsible for the hours of the day rather than the Egyptians, although I imagine it's hard to know who came up with which of those first.
This has always bothered me. Our time system is so weird but I also found it strange that the whole world uses the same weird system.
Well everyone understands mathematics differently.
12 was used because it is divisible by 1,2,3,4 and 6. This was vital when buying, selling and trading. The number 60 came from 12x5. As you said, also divisible by 1,2,3,4 and 6 along with many larger numbers so great for trading again.
Trace, it pronunciated "si-de-rial" not "side-real" nothing to do with "real" or "sides" :-P
I was confused as well, he should start to include scientific terms on screen.
OMG IVE NEVER SAID IT OUTLOUD.
i'm dumb.
No, you aren't, Trace Dominguez. You do several clips a week covering wildly different scientific topics with scientific language. I just happen to know stuff about space. If it had been chemistry or sociology, I would never have noticed. 😂
I agree, this guy is passing himself as an authority in everything, when in fact he's probably ready Wikipedia
Erik Münso: That is a good piece of advice for all these legitimate videos and documentarys. All too often the key words are not understandable when spoken and recorded, it would be best to show them spelled out on the screen, like it really was an educational experience.
Here's the real reason:
Before all the highly accurate chronometers, scales, and yard-sticks, the only way to measure ANYTHING accurately was to compare its parts, e.g. my half of the pound is equal to your half of the pound, so we each have 8 ounces.
Extend this to time: it takes an entire day for all this sand to run through. It takes half a day for half of the sand, etc. The division of products, and hence the division of time, was based on the most accurate way of dividing through comparison of parts, which inevitably resulted in a number of ounces, cups, feet, and yes hours, with lots of usable factors.
The 24 hours were divied up thus to accommodate easier fractions. You could do a half day, a half daylight, a third of a day, a fourth of a day, giving easy ways of paying for labor, honoring contracts etc.
You see this same principle in the imperial system of measurements: Gallons are easily divided into quarts, which are easily divided into pints etc., because making two or three parts equal is much simpler than making 10 parts equal (which would be required in a base 10 system).
This is why a foot is 12 inches, why a circle is 360 degrees, why a minute and hour are both divided into 60 parts, and why a day is 24 hours. That's all there is to it. (Side note: 365 days threw a wrench into it, since days and years don't naturally factor into each other, but we still divided the year into usable parts: seasons.)
The knuckles thing with the Egyptians is a happy biological coincidence that there happened to be a part of their body that corresponded to the already-useful system of measurement. Think about it: why would anyone think of using their knuckles before thinking of using their fingers?
The cultures mentioned, which have a base 12 or a base 60 system (I think your source may mean a system BASED on 60, not with a BASE 60) follow this approach. 60 easily divides into factors the same way. It is "magical" because of it's incredible practical nature. It's possible lore followed it for that reason and gave it a magic aura, but it would have followed, not led, the usefulness.
"Hour" from Latin hora; (by way of Greek ωρα); minute from Latin Minutus from verb minuere (to lessen/decrease) from Greek μινυθειν; second from Latin secundus derived from sequae...
Do you know that in ancient Sri Lanka, a day was divided into 60 (shorter) hours, not 24.
The math is still the same - 24, 60 or 360 degrees in a circle - all divisible by 6. In remote northern Australia, where I come from, the indigenous people name 8 different in a year.
Speaking of time, it's not called BC/AD (before Christ/Anno Domini) anymore. We use BCE/CE ((Before) Common Era) now.
But that doesn't hide the fact that Dennis the Little based the numbers for the years as the number of year 1AD which was the year he calculated Christ was born.
Note: there is no year 0 AD or 0 BC as the concept of zero had not been invented when he set the year numbers in 532 AD.
If 2000 CE was the *start* of the 3rd mullennium CE then there *must* be a year 0 CE; meaning all the history books are wrong regarding any date pre 1AD being translated from BC to BCE - 45 BC is equivalent to 44 BCE!
Unless 1000 BCE is considered as the last year of the second millennium BCE in which case there must also be a 0 BCE (different to 0 CE) and 45 BC is the same as 43 BCE.
I watched like 7 of your videos in a row!!! I had 2 subscribe to u bro I like how u present the facts and break it down plus u are completely unbiased in all conversations u had so far keep up the good work bro👍🏾
I came up with my own units for breaking down the day. A day is 2 clocks, where a clock is the time for the hour hand on a clock to go around once. A clock has 3 meals, and a meal has 4 hours. So a day has 2 clocks, 6 meals, and 24 hours, and a clock is three meals, the three meals we eat in a day. Then I invented another way. A day is 3 shifts, a shift is 2 meals, and a meal is 4 hours. This breakdown of the day is familiar to shift workers.
The lack of graphics infuriates me.
maybe you should eat a snickers
He only cites 22 hours when talking about the division of day, night, dawn and dusk. At ~4:34 he cites 10 hours for day, 10 hours for night, and 1 hour for dawn and dusk respectively. Not really worried about it, just happened to notice.
The # 360 is evenly divisible by every number from 1 to 9 with the exception of 7.
And 10, 15, 20, 30, 45, 60, 90, 180. In a pre-electronics era base 60 and 12 are extremely practical.
1:36 it is pronounced si der real
1:08 did he just say flattened out into a disc...
Flat earth theory?
Okay, so I get that the Sumerians had a number system of 60 based on the degrees in a circle, but who decided that? Who decided how much a degree is?
The earth spins on its axis counter-clockwise only when looking down on the north pole; when looking down on the south pole, it turns clockwise. 23 hours 56 minutes is the length of time for the earth to make one rotation on its axis; 24 hours is the average length of time between solar noons.
I actually know all of the information in this episode before watching! Proud!
I always thought the hour was defined by how much later the moon rises from one night to the next.
whatsup with the hate comments on the format style? I actually like this podcast style. It's nice to not be bombarded with visuals and hyped up graphics for a change.
keep it up trace!
Well this was extremely informative. Not sure what I would do with this info but it's nice to know. Knowledge is power.
60 is also special in this way: keep counting to from 1 to 12 in the egyptian manner with ur right hand (use ur right thumb tip to count the segments of the remaining 4 fingers, i.e 4 fingers x 3 segments = 12), and keep closing a finger of the left hand (from thumb onwards) whenever u reach 12.. basically u get 60 = 5 x 12, thereby relating the egyptian and sumerian number systems..
I was thinking about why we have 24 hours in a day this night, and my own logical conclusion was that it was derived from dividing a sun dial into segments.
Cut it in half you get 2.
Again and you get 4.
Then take these 4 slices and divide in 3 each.
You wil end up having 12 slices.
Now double that for the night time, and you get 24 hours in a day.
Not so sure about the joints idea. Try drawing a circle using a compass then use the compass to sweep arcs and divide the circle up. Dividing it 12 ways is easy, 10 is difficult. Furthermore it is easy to subdivide 12 into smaller equal parts, not so with 10.
Since dividing up and sharing small amounts would have been key to early societies which used barter a lot, the 12 system worked better on all kinds of levels.
The English set the standard because they were the first to have high speed transport (a large railway network). Time differences even across this small country caused all kinds of problems not apparent before, the most obvious being time tabling.
Find a Egyptolgist who can confirm they had "a compass" 5000 years ago ?
@@Rusty_Gold85 What has a compass got to do with time? Furthermore The Babalonians divided up time in this way with 365 days approx. They knew it was not exact. Long before the Egyptian empire. The Sumarians used the base of 60 long before them.
I like the talking-point buttons at the bottom. I wish more youtubers would do that.
Not just any caesium atom, the caesium 133 atom :-)
hurray Trace is back!!!!
Where are the 4 minutes missing? When accumulating them we'd drift off for 24,333... hours per year (in 6 months midnight would be noon on the watch). We never adjust the watch anyway. It's exactly 24 hours per day, the second got adjusted to the movement of the earth. Time counting is indeed man made.
They aren't "missing" - that's just the difference between the true rotation period of the Earth (wrt the distant stars, since that's a non-rotating frame of reference) and the length of the average day, for the Earth to rotate once + an extra little bit to bring it back to presenting the exact same face to the Sun, so that wherever it was exactly noon yesterday, it will be noon again today.
There *is* a difference because in that day, the Earth goes about a 360th of a circle around the Sun.
Thus the sidereal day - Earth's true rotation period - is about 4 minutes short of a (mean solar) day - noon to the next noon.
So in 6 months, if your clock counted sidereal days, you *would* find noon on that clock arriving at midnight.
Fred
What about the Sumerians??? Why most ppl dont talk about them. They r the creators of time, as far as we know so far. Please give those guys some credit. Forget about the ancient astronaut theory, but lets just look at the historical point of science. They were real they were AWESOME. Great fan of the show by the way. Thanks
same that I was going to say, it was the Sumerians!!!
You might check out the ancient vedic tradition of India - which was WAY more ancient than Babylonian or Egyptian cultures. Based on direct cognition of the workings of the fundamental laws of nature, they had solar days with 24 x 60 divisions (like our 24 hours and 60 minutes), months of 30 days, years of 12 months, lifetimes of 100 years...long before any of the cultures that you refer to.
I loved this episode! ^_^
Glad you enjoyed! :D
+DNews Plus Oh my!!! You guys replied. That's so cool😄😄
My bong toke brought me here...
00:48 Counterclockwise? No. Well, maybe, depending on your perspective. If I am directly above the south pole, the earth will spin clockwise. From the north pole, counterclockwise. From the side, from east to west, maybe left to right, unless I turn upside down, then right to left, or 90 degrees top to bottom, or 270 degrees, bottom to top.
Then again, the world could be flat with the universe rotating around it, which was conventional thinking for many years, and still is for the Trumpkins.
exactly
im pretty sure he meant to include "relative to our sun"
+Lil' Canada still its our own perspective whether we are checking from above or below (assumed) the solar system
Lil' Canada Relative to our sun would be left to right, not counterclockwise. If one takes the tilt into consideration, it's clockwise half the year, counterclockwise the other half. But from the sun, one would always say left to right because at no point would either pole directly face the viewer.
America should try that so we can rewin WW2!
If you read the Quran of the Muslims, Mohammad said that believers should never support the seven days of week or solar time. He supported the concept of lunar years. This was why Muslims calendars are totally unlike Roman or Catholic calander.
He was a idiot
base 12 is a natural way to do arithmetic without resorting to math, paper, or calculators. you can naturally divide by 2 (ie fold) to get page signatures, carpentry measurements, and websites (most are designed over a 12-column system which uses this folding in half effect to adapt to mobile devices). It's more flexible for many everyday, non-scientific applications.
I hope y'all cover all the ways we've messed up time: calendars (and the messed up conversation between them), different epochs, timezone (countries moving them), issues with DST, leap seconds (different ways they're calculated and Google using a half second to avoid errors), US (and I suspect other country's) holidays wrt programmatically calculating them. I'm sure I missed at least one or two other messed up things we've done with time too...
Oh and the convoluted way we think of time on the Gregorian calendar AD/BC(E), t0 vs 1st century. And trying to have a partially lunar/solar calendar. Also should comment on the end of 32bit epoch :)
Hey Trace! Another great walkthrough!
I have a small piece of constructive criticism... It feels kind of weird that you keep breaking eye contact to look into your laptop. It's like when someone's talking to you but keeps looking at their phone catching up on social media or something. A little distracting and not so engaging. Maybe if you put a screen near the camera like a prompter type setup?
Other than that, I really appreciate your work and love your clear, step by step explanations.
Thanks!!
I love how people of the scientism faith talk about the big bang and formation of planets like it's not a theory. Gets me every time
May be a little off topic, but do you think you could cover technological singularity and how it'll affect humanity?
This really made my day
Could have it metricated - where 10 metric hours = 24 hours = 1 day, 100 metric minutes = 1 metric hour, and 100 metric seconds = 1 metric minute. I worked it work, the metric second would be a little less than the second. Could also use Battlestar Galactica original series names, like metric second being a micron, and metric minute being a centon.
Micro means 1/1000. A microscope was supposed to allow someone to see something 1000 times smaller than normal vision although most microscopes don't actually do that.
I believe science is more unbelievable than religion.... Science is not a big deal. Science also believes in the unseen (like big bang), and it's dogmas.
How do we really know a Monday is really a Monday? Are we positive since the first Monday someone kept track of this and we are on the correct Monday?
I'm glad you're finally doing the topic of calendars. I've been wanting you to do this topic for a long time now. It's good so far. Great video as per usual. Keep up the good work.
The funny accident, if it's true, is that the ancient Egyptians chose the best basis for a number system, with only one potential divisor out of six that doesn't result in a whole integer! Pure serendipity!
Another fortunate accident may have been the Sumerian base-sixty system, that integrated the number five as a divisor that also included the number twelve with all its other integer divisors; a geometric advantage to this is that an optimal polyhedral spheroid approximation has sixty equilateral pentagons evenly symmetrical in their placement among all other polygons that are identical equilateral hexagons of similar area. The geodesic potential of the Sumerian base-sixty system would be a major advantage in ocean navigation, and that geodesic happens to be the precise shape of C60, the famous Carbon molecule called a 'Buckyball', which is a Fullerene!
It may have been true that ancient people had a more sophisticated grasp (pardon the pun) of numbers than known history suggests as based on finger joints! Ironically, the modern accepted legacy of the base-ten system seems to be based on our number of fingers & thumb! This legacy of base-ten is a lousy system that convolves into complex mathematics that could have been the much more versatile base-twelve system instead! The ten-base divisors omit two integers out of five, whereas the twelve-base system only omits one integer divisor out of six! 1,2,3,4 & 6 versus 1,2 & 5. Imagine expressing 1/12, 1/4 or 1/3 each as a single 'digit' fraction of the base. But noooooo! We're now stuck with that stupid ten-base system even for scientific notation!
Fortunately, computers don't give a shit about those primitive systems! Binary numbers can't get simpler!
Tracie my boy, I missed you
amy was equally good
+radulescu valentin (love introvert) trace is excellent. I agree. but I feel Amy too is g good (not as good as trace maybe)
*Tracy
That's how I spell it lol
GONG! Sidereal is pronounced sigh-DEER-ee-al.
On another note, base twelve is vastly more practical than ten because it's evenly divisible by 2, 3, 4, 6, and nearly by 8 and 9. 24, 60 and 360 are all multiples of twelve and even packaging is easier that way.
How can we measure time from a star if the earth is also rotating around the sun, and our solar system is spinning around the sun. All while flying through the universe with NO fixed location. Unless the earth is not moving then what you said makes sense.
Stars are very far away. they appear motionless over an average lifetime. With instruments we can actually measure the closer stars movement in reference to the more distant stars.
Welcome back Trace!
Interesting video! Great work DNews Plus!
There's a show called Netflix "How We Got To Now." that discusses how Time came to be in the modern world, not going far back, but just far back enough that it's relevant.
I figured it was the Egyptians. Time was very important to them. They had a million people in the Nile River Valley as early as 3000 bc, and it floods at the same time every year.
Everything modern came from the Egyptian / arab knowledge conquests. So many different informations out there, but it's always consistent that They discovered more scientific marvels of life and specifically the human psych than any of us will ever be privledged to see / know.
What would we do without Arabic numbers? Roman numerals? AARRRHHHGGG!! The Middle East DID contribute something to the world.
Swinde
- Thousands of years ago there were intelligent people in the middle east. Nothing wrong with the real estate, its the people who live there that are the problem.
That is true. The Babylonians are responsible for much of the progress of the early times. It was located in Iraq. Much of math originated there.
Science Plus - years ago when I was in a high school (USA) math class I said something about a "hyper-bola" curve and everyone laughed - well, some of the class laughed. "English as she is spoke" can be strange. Some of the other people have chimed in about "seh-DEAR-eh-el" at 1:37 not "SIDE-re-al". Words are not always pronounced as the are spelled - the division of syllables is not always obvious, nor is the emphasis for each syllable. Try Google Search [pronounce (some word)]
BTW the Earth spins counter clockwise if you are viewing it from above the north pole. Note that if sundials and mechanical clocks had been invented in the southern hemisphere, clockwise would be the other way.
It was the advent of faster time travel by train, then telegraph, that made standardized time zones necessary for schedules to make sense. Accurate time-keeping is necessary to determine longitude at sea and Britannia ruled the waves. The Earth turns clockwise if you turn the constellations upsidedown, but that would turn mythology on its head.
I've been waiting for this episode ever since I understood the concept of time
Wonderfully informative. Great video
I wish we had a global time zone. We could abolish time zones and make it so 6:00pm in New York is in the evening and 6:00pm somewhere else is in the middle of the night there. This would stop confusion and make it much easier for future space dwellers. I also think we should completely change the way we tell time. There should be ten time units in a day, 100 decitime units in a day, 1,000 centitime units in a day, etc. This will most likely never happen but it would improve the way we tell time (in my opinion). Metric time-keeping system?
Global time zone is great as long as problems like blackouts and lack of access to clocks is addressed.
Someday...
not practical for historians and bankers.
Would make it awkward for international calls and communications etc. It'd be harder to appreciate the difference in the time of day when communicating with other countires as you'll now need to find out how far ahead and those people are in their working day as 9 o'clock will no longer imply that it's the morning and so on. As for those in New York, they would have to get used to a 2pm-10pm working day which I'm sure would be strange for them and the rest of the world whould find their times shifted. (we'd in all likelihood stick with GMT if it was going universal)
Yeah, it would be hard to make such a large change. It would mostly make sense for it to be used for interplanetary purposes.
China has 1 time zone for the whole country. Ideally, they should have more than 3.
Didn't mention that the 24 hour day varies slightly, and is never really exactly 24 hours anyway.
Hey, wasn't this testtube plus? When did it change to DNews plus and why?
I INDIAN PEOPLES OF SANSKRIT LANGUAGE PERIODS HAD A TIME MEASURE CALLED A PARASONG..WHICH IS 1/60TH OF A SECOND!IT IS IMPORTANT FOR THE MEASURE OF TIME WHEN TIME TRAVELING: TO RETURN AND ARRIVE AT AN "EXACT TIME IN REFERENCE TO HAPPENINGS WHICH ONE IS TRYING TO ALTER ,OBSERVE OR ENHANCE SUCCESSFULLY AND PRECISELY!!
Aww you guys :D I'm so happy Amy came in so I could take a week off and go to SVALBARD and the LARGE HADRON COLLIDER!! Got some great interviews for y'all! Stay tuned. :D
Horus = Hours
Minister = Moon star = Minutes
secundus = 2nd progression Mercury
The three hands of a watch relate to the three planets associated with time. The slow hand is the hour hand, meaning Horus, the sun. The minute hand is for Min, the moon and the swift ticking hand is for Mercury, the planet which rotates fastest of all, both round the sun and on its own orbit.
Excellent! Well done! Thumbs up!
Now that Google Music supports podcasts, will you guys be joining the program? I'd love to just stream it at work!
+Steven Clift Ha! Well that escalated quickly.
it is divided into twelve because of 12 signs of zodiac belt. As per vedic astrolgy, each sign is divided into two horas, which makes 24 horas a day. Each hora takes an hour approximately so 24 hours a day.
With 23 hrs and 56 mins each rotation or day... that equals 364 days per year. So if you divide that up into 13 months its 4 weeks per month with 28 days.
3:25 - it'll be noon where you are and 12:05 a city an hour away???
I thought a side-reel was the DVD extras. I guess I learned something already.
[GRIN] Yeah, that pronunciation creased me up! =:o}
It should be pronounced "si-DEER-eal".
In an expanding Universe, why would a gaseous cloud collapse at all?
Gravitationally bound objects aren’t expanding, but the space between them is.
There is 86,400 seconds in a day.
The sun's diameter is 864,337 miles.
So, for every 1 second the earths rotation covers 10 miles of the sun's diameter (Just out a touch)
Is this how seconds were originally calculated or is it just coincidence?
How about dividing the day into 48 parts instead, 30 minutes each? That way, if we really must continue observing Daylight Savings Time, then do it more often, but move only by 30 minutes each time. I don't mind so much that it happens, but that the change is so abrupt.
I can hear Australians screaming "The Earth only spins counter-clockwise in the northern hemisphere!"
They say we use 10 digits because have 10 figners but if you watch closely you will see that 10 has two digits in it, plus do you start counting your fingers from 0 and finish at 9 ? I know I dont...
I don't think the Egyptians used base 12 to count because of finger joints. I'm fairly certain the reason they used 12 is because 12 is divisible by 1, 2, 3, and 4 which means you can divide a whole into half, third and quarter evenly, where as with 10 you can only evenly divide it by 2 evenly.
Counting finger joints probably came after the invention of base 12.
The reason for using 12 that I suggest is not the number of finger joints, and not factors either, but because it decomposes into 1,2,3,3,2,1. Please see my comment just two above yours and tell me your opinion.
hey trace! I'm going to space camp in August and I was wondering if you have any advice for me? I'm a little nervous and wanted to talk to a space camp alumni! thanks !
It's great! don't worry, everyone is in the same boat as you. Make sure you try everything, and just have a great time. :D
Trace - You've probably already got feedback on this, but "sidereal" is not pronounced as 2 syllables, like the words "side" and "real" pasted together. It's 4 syllables: "sye-DEAR-ee-el."
Same with "siderius" - also 4 syllables: "sye-DEAR-ee-ess."
Fred
That's why British currency was based on twelve, because of the factors of twelve, was greater than ten, ergo... easily devisable.
When did they figure out, the complete rotation of the earth in 23:56 hours
For a more thorough explanation, read The Discoverers
"They [the Egyptians] divided the day up into 12 parts each. . . why 12?" I think one answer is to be found in the so-called "rule of twelths" still used today.
"The rule of twelfths is a rule of thumb for estimating the height of the tide at any time, given only the time and height of high and low water. This is important when navigating a boat or a ship in shallow water, and when launching and retrieving boats on slipways on a tidal shore. The rule assumes that the rate of flow of a tide increases smoothly to a maximum halfway between high and low tide before smoothly decreasing to zero again and that the interval between low and high tides is approximately six hours. For the six hours, the rule says that in the first hour after low tide the water level rises by one twelfth of the range, in the second hour two twelfths, and so on according to the sequence - 1:2:3:3:2:1." (Wikipedia)
But why divide up the tidal range into twelths and define the hour as one sixth of the time taken to cover it? I suggest because the sequence 123321 aptly describes the rise then fall of tidal flow speed as well, since it sums to twice the quantity of integers it consists of, 6*2=12. Any other integer sequence of that exact pattern, say 1221 or 12344321 does not.
I think it's easy to see how we then get to the primarily tidal rather than astronomical cycle of a 12 hour time period from there, especially as many early civilisations were maritime. A water clock connected to the harbour with a face divided into 12ths could have been useful for deciding when to set sail, day or night.
ur videos never seize to let me down
shouldn't that be cease? just helping.
maybe he's have a seizure?
seriously? swanclipper i swear everything someone types gets hate xD i gave the guy a compliment ffs
FreaackyFreeky and i helped you by telling you that word was wrong. being kind doesn't remove spelling abilities. i could tell you how awesome your comment is, which it is, but i can't let you go around using the wrong word.
just helping. bare in mind, i'm not belittling you, bringing you down nor am i causing a fuss.
hell, i even have a problem with "ur" but since you used the wrong spelling i had to let you know it isn't the right word. you can compliment whoever you want, you can be as rude as you want, i'm still going to let someone know if they're misusing something.
+swanclipper I can say wht i want if u can understand it. yes I realised I said wht and u. but u understood it.
"Yeah... that was invented in the 16th century.... So pretty recent" - That totally made me laugh for just the irony
you can tell he's frome michigan when he defines the distace between 2 cities by how long it takes to get there.
Egyptians....... I think you mean the Babylonians sir!!!!!!!
Also called cushites
Is that a mean word or something?
I don't know :_:
Bat today I didn’t know they were the same people, I always thought that the cushites came from around the Sudan area and basically took over Egypt hence why there are more pyramids in Sudan than Egypt. It’s a shame how there is very little knowledge amongst the general public about even the existence of the Cushites let alone how they shaped Egypt.
random cat ........ seriously?..
Well that answered some questions I've had since childhood
Usually people hold just one joint with their fingers. If you hold three, well, more power to you
After finding that 360 was very much divisible, we could have switch to a 6-days week. Would have simplified the calendar: 12 month of 5 weeks of 6 days. And one week (5 or 6 days) remain, that we can either add somewhere as a whole week, or spread it more evenly in the calendar. On the other side, 7 days per week, that gives about 52 weeks per year, and 52 is 13 times 4. As far as I can see, the only reason we did not change was tradition. Ahh humans...
Is the counter-clockwise spin of the earth totally random or becue of the spin of the galaxy as well?
Could we have formed from the cloud of dust with a clockwise spin?