Interesting that the pole star never changes while we are hurtling around the sun racing across the universe while wobbling crazy on our tilted axis and spinning wildly around... and yet the same star above us every night for thousands of years....

"Knowing your relationship with the sky" Exactly !

Anyone agree with this: Not knowing much about the night sky does create some agitation within my being. Not knowing my surroundings on a basic level feels unsettling. I never realized this until this video. So thanks!

What most people forget to mention the beautiful scientific history of the divice is that the name Astrolabe comes from the Arabic (Al Astarlab) which comes from the Persian (Sitara Yab) which means Star finder, star tool , star instrument, star access. in light of scientific integrity its crucial to note that the Astrolabes were perfected by the Arabs Universities in middle-ages (13th - 14th century), by Predominantly Persian scholars based on the rudimentary Astrolabes that were first invented in Egypt during Ptolemy's time and the first work was done by the Greeks. these entered Europe through Islamic Spain. thats why the oldest Astrolabes are always in Arabic. From Greek - to - Egypt - to - Byzantium - to - Persians - to - Arabs - to - Moors in Spain - to Europe The Mater comes from - Um (mother) The Plates - Lawhat (Writing slate) Rete (web) - from - Ankaboot (spider) Central Pin - from Fars (mare or) Faris - (the rider) Ruler - Al Idada (the ruler)

This is something I would like to learn one day. A sundial can give us the time during the day but would fail at night. Tech is a two-edged sword. It can be wonderful, easing our labor. But how people adapt can be a problem. As the lecturer in the video spoke of how people lost the understanding of the movements of the heavenly bodies, so have others lost something when new tech came about. A few generations after the calculator came out; it has produce so many that don't even understand fractions. I had a person who had already graduated from high school insist that 1/4 was larger than a 1/3. His argument revealed to me that he didn't even understand the concept of a fraction. So many cashiers now can't make change unless the machine tells them what it is. Schools are now teaching new algorithms (new math) to cope with children not mastering basics like the multiplication table. New algorithms like "reasoning" (I call it guessing your way to the answer) may work but it isn't efficient as it requires more steps. I suspect one day when self driving cars are mandatory, (and likely be safer) driving a car will become be a lost skill for many if not most people. Imagine 20 years after the teen takes a two week course to get a certificate showing they know how to drive a car. Then they don't drive a car for the next 20 years and one day they are caught in a snowstorm. The car pulls over to announce there is a malfunction (frozen sensor?) and goes into manual mode. The driver has no reception to call for help and is forced to drive or freeze to death. This is the problem with technology. People tend become too lax and lose the ability to cope. GPS/Unable to read a map, Spell-checker/inability to spell, Computers/lost manual research skills etc. I had to show a 16 year old how to use an actual dictionary. His argument was he didn't need to know how as his cellphone will do it for him. But if the battery is dead, or there is no reception, then he remains ignorant. I don't blame the tech though. I just insist on teaching everything from the use of technology to hands-on skills to cope without tech. It requires discipline to do this as most kids tend to be hedonistic. Who knows? The knowledge may even save a live one day.

"Imagine the Earth is at the center of our universe. " Psalm 104:5: “He set the earth on its foundations; it can never be moved.” Ecclesiastes 1:5: “The sun rises and the sun sets, and hurries back to where it rises." It IS the center of the universe.

It works because it represents flat earth model, not a globe

Totally eye-opening! I remember - vaguely - having to learn about this contraption in 8th grade History class. All we had to go on was the term "astrolabe" and a horrible definition as to what it was. Glad I can finally see one and find out not only what it looked like but how it was used. Thanks for filling one of the voids left from American public schools for an autodidact who likes to do that sort of thing. ^.^

I want an astrolabe for christmas, A great example of form and function combined.

Great presentation. One of the best I have seen on TED. Thank you

Amazing what they came up with way back then!

The real Golden Compass... coool!

Very impressive! First smartwatch 😉I now wish I had some knowledge on astronomy 😀

Great lecture!

i also like the looks of the device!! such cemetrical patterns are possible because the universe is a fractal.

How high are you supposed to suspend it? Won’t the altitude of the celestial object change depending on how high or low it’s being held? I’m a bit confused if somebody could please enlighten me.

Of course....they wouldn't work too well in cloudy skies. Otherwise, I have to admit, this is one of the coolest things I've ever seen.

A very interesting viewpoint on technology.

An Astrolabe can also be used for: Timekeeping =========== Determining local solar time. Finding the time of day using the sun. Determining the time at night using stars. Calculating the length of daylight. Predicting the time of sunrise. Predicting the time of sunset. Measuring the length of the night. Finding the time of solar noon. Converting solar time to clock time. Determining the duration of twilight. Astronomy ========= Locating stars in the night sky. Identifying constellations. Determining the altitude of a star. Measuring the azimuth of a star. Finding the declination of celestial bodies. Measuring the right ascension of stars. Predicting the positions of planets. Calculating the altitude of the sun. Finding the position of the moon. Tracking the motion of stars across the sky. Predicting the appearance of new stars. Calculating the celestial coordinates of stars. Navigation ========= Determining latitude by the altitude of the sun. Finding latitude using the North Star. Establishing longitude through time comparison. Navigating using the sun’s position. Navigating by the stars. Using celestial bodies for maritime navigation. Correcting compass readings. Establishing a course based on star positions. Identifying geographical coordinates. Planning sea voyages. Verifying map locations using celestial observations. Surveying and Cartography ====================== Measuring angles between landmarks. Determining the height of objects. Calculating distances using triangulation. Mapping land features. Aligning maps with true north. Establishing boundary lines. Surveying building sites. Plotting the position of celestial objects for map making. Creating accurate topographical maps. Assisting in archaeological site surveys. Educational Purposes ================== Teaching principles of astronomy. Demonstrating the celestial sphere. Understanding the ecliptic and equator. Explaining the apparent motion of stars. Teaching navigation techniques. Illustrating the movement of planets. Demonstrating the concept of latitude and longitude. Educating about historical timekeeping methods. Showing the relationship between the horizon and celestial objects. Explaining the concept of celestial coordinates. Calendrical and Chronological Uses ============================= Determining the dates of equinoxes. Finding the dates of solstices. Calculating the date of Easter. Determining the phase of the moon. Predicting lunar eclipses. Calculating solar eclipses. Converting dates between different calendars. Establishing the beginning of the seasons. Determining the length of the year. Predicting conjunctions of planets. Astrological Applications ==================== Casting horoscopes. Determining the positions of planets at birth. Finding auspicious times for events. Calculating astrological houses. Analyzing celestial influences on personality. Predicting future events based on star positions. Matching horoscopes for marriage. Determining the best times for planting crops. Religious and Ritual Uses ===================== Determining the direction of Mecca (Qibla). Establishing prayer times. Finding the dates of religious festivals. Calculating the Islamic calendar. Determining the timing of Christian liturgical events. Finding the best times for religious rituals. Assisting in the alignment of religious structures with celestial objects. Practical Daily Uses ================ Planning outdoor activities based on daylight length. Scheduling agricultural tasks. Determining the best times for fishing. Planning travel based on daylight. Establishing the timing for ceremonial events. Scientific Research ================ Observing celestial phenomena. Collecting data for astronomical research. Studying the motion of celestial bodies. Measuring atmospheric refraction. Comparing historical celestial data. Verifying the accuracy of modern astronomical models. Other Uses ========= Creating artistic representations of the sky. Serving as a decorative object with educational value. Enhancing historical reenactments. Providing a cultural artifact for museums. Inspiring literature and poetry. Assisting in the design of sundials. Studying ancient scientific methods. Verifying historical accounts of celestial events. Supporting the preservation of historical navigation techniques. Acting as a symbol of scholarly achievement. Facilitating interdisciplinary studies between astronomy, history, and culture.

When he asks how you would check the time, he mentions the iPhone. When he talks about the cost of an astrolabe, he uses a reference to MacBook Pro. Holy shit! Could we have another shameless plug for Mac please?

All with no wires. Amazing.

What did one do when it wasn’t night time? Also, I can’t wait to check out a more detailed video explaining how this works. He didn’t quite reach me with it.

I think that you raise a good point, really progress is a form of change. You could think about it as the vector of change if you wish. The counter point being oscillation. I know theses are very mathematical terms to try to use to describe human endeavor, but why not they seem to fit.

Awesome! Really smart people!

We do grow more and more remote from our surroundings. A co-worker once asked me for directions. When I mentioned heading N. or E., she told me that she didn't know where those were, even though she'd driven there. I wound-up having to draw a street map.

Lol! This is great. These people are trying Desperately to NOT SAY "It works by assuming or imagining the earth is flat and stationary with the heavens attached to the hemisphere dome. They didn see earth as a ball at all!

The astrolabe shows local time, the iPhone can only show standard time. It's different.

credits to the real Astrorlabe inventor, first man to ever assemble a functional astrolabe. Al-Zarqali (Arzachel) [1028 - 1087]

Does anybody really know what time it is?

You have any article on the astrolabe?

I'm usually out the same time in the evening so I thought that this was perhaps why I see it in the eastern sky. It's so very bright & unblinking, I didn't think that it was a planet because it makes no difference what time of year it is. I'll check out the nasa site.

@kamratframjandet The sun works well during the day (hence the sundial), but the astrolabe helped a great deal at night. Conversely, the seafaring world had to wait for an accurate clock system to tell them the time so that they could use the reverse process to determine their longitude.

Fascinating

I thought Chaucer invented it but………..330 B.C.? Weird, right? And the sky was projected on a sphere? No it wasn’t. However, it did work perfectly with the earth set up as the center of the universe and it works today!

Actually it was extremely interesting how in the 13th century they had already made a calculator and practically a computer. But I know what you mean because I too was expecting more about the history of its making and about the significance it had to the Muslims but either way it was very nice

Yes, at night it's usually in the eastern sky where I live.

I don't drive. I take public transport or walk. I don't walk around with a compass but I do like to know basically where I am on the cardinal points. It's helpful to know when you're travelling around, so using the sun or even where the position of the space station is in the sky is helpful.

@megalibra82 Would this be the same Wikipedia that says it was invented by the Greeks around 150BC?

Do you look at time on your Iphone? I tell time by looking at my watch!!!

yes that is a very very good place to start..

wonderful! "Does anybody really know what time it is?" Chicago

6:22 in the heaven? where is it?

@megalibra82 he did mention that they date from ~300 BC or so.

I agree but still it was quite informative...

does it say anything about whats going to happen on 12-21-12? rhetorical ...

@SingleSpiral TED Technology Entertainment Design. This is incredible technology, It is entertaining and it involves something with incredible (and beautiful, in my opinion) design. IT fits TED perfectly.

Good vid.

Yes, it was his interpretation that all change is progress and all progress is change that seemed too simplified for me. I always thought of these as two separate words with two separate definitions. Progress always progresses, but does change? You could make the argument that everything we see progresses because only nonexistence is true stagnation, but I'm just talking about the meaning of two words and what they represent.

What About Hypatia? I thought she created it in Alexandria

The first astrolabe inventor was Greek and his name was Ίππαρχος (Ipparhos) from the island of Rhodes in 2nd century b.C. The word astrolabe is Greek : αστρολάβος. It"s sad when in videos like this one you don"t hear the information and the history that lies behind such a magnificent device.

to bad my astrolabe has such low reception where i live.

Now you all know what the real purpose of shields are.

got one for a Christmas Present, will it work for the southern hemisphere?

To all those negative comments- What message were you expecting? I bet you didnt know of the astrolabe! I learned something therefor it was of interest. Side note: Its interesting to see the evolution of man's progress in technology. And yes - I was amazed at how they could come up with this stuff even TODAY let alone so many years ago. I would wager not a single high school (students) in the USA could create such a device today if asked.

did not know these existed

almost 19 million subs 100k veiws and not even 1k comments

“Holding a model of the universe in my hand” hmmmm its flat?! 💡 “What we gain with technology is precision and accuracy, but what we lose I think is an accurate sense of the sky, a sense of context….” truth!

I usually know quite well what time it is just by looking at the sun, unless I'm totally confused about which way is north or south...

I don't think anyone ever claimed it was. The speaker referred to the "first technical manual in English" on how to build one. He never said the author of the manual invented the device, nor that there were not pre-existing manuals or devices in languages other than English. He was only pointing out that the first instructions on how to build the device in his (and most of the audience's) primary language were targeted at an 11-year old child.

I am always amazed at how people put forth such amazing technology and such, at the time, abstract thoughts. However, if this ted talk was truly only about the astrolabe it was an ill conceived ted talk. It is an amazing device, but a ted talk should move you. Maybe if he did not use an iphone app to write his speach it might of had been more directed. So much could be said about the invention of it, rather than the expense of the object itself. Who cares what it costs?

I must disagree with him that progress is just another word for change. Even though we cannot have progress without change, not all change is progress.

The commercial wasn't about going green or saving gas, or any thing of the sort. It's about a solution to a problem. Too many people on the road when they do not need to be. The addition of a simple fee was all that was needed to deter those with no real reason to be out driving and facilitated faster, easier traveling for those that did need to be on the roads.

the device requires the earth to be a flat plane, and the sky to be a dome for it to work... it does work... therefore, the earth is a flat plane, and the sky is a dome.

how come i have never heard of this?

What a beautiful device!

Could one not program an astrolabe on the ipod?

Would you please put your 24/7 feet back up, I really enjoy watching that

as a follow-up, where we would say the stupid phrase, "there's an app for that," the old folk would say "learn your stuff, you damn yuppie." well... something like that.

Use 2: paper weight

agree.

Affirmative =)

and Orion has just popped up for me in Maine. right of the rising moon and that's right of the birthing sun.

Megacool! Made me realize that Islam helped the development of Astronomy because Muslim travelers had to figure out the time for prayers and the direction to Mecca!

i wonder if it ever dawn on these people that this works so perfectly because the earth is flat.

An astrolabe requires a flat plane and a domed sky. If you go just one level further into the math and geometry that goes into using this, you would see this. This guy couldn't say this because it's against the narrative

extraordinaria simplicidad en la exposición para un dispositivo aparentemente complejo! felicitaciones! en la computadora se puede instalar el programa stellarium con el que se "descubre" que el astrolabio es una ingeniosa combinación de coordenadas ecuatoriales y azimutales! stellarium.org/es/ en mi celular tengo sensor magnetico asi que trabaja una app de brújula y entonces también funciona perfectamente la app SkEye que recomiendo usar! saludos desde el peru

Cool ★★★★★

The only issue is that they only work in one location, right? Very impressive nonetheless

interesting.

whatever, you get the point. timex, it takes a licking and keeps on ticking

dude, his point is we over-rely on technology, and we think that the only way you can do simple tasks is to use the newest, "best" technology. he's saying that we think we're so advanced because we have new gadgets, when in fact there are old ones that are jut as good.

He says imagine the earth is at the center of the universe at 2:20. The ancients BELIEVED the earth was at the center of the Universe. They also knew the Earth was flat. That's how they built the Astrolabe. It worked then it works today. What do people in the Southern Hemisphere do? People in Australia can't see the North Star.

strangely, in this day and age if someone asks what time it is - the first thing you do is check their IP address to see what country they're in. Strange times :)

I came here from Game of Thrones

So this Earth is stationary!

Shoutout to John B McLemore

it's time to say I love myself:) and you

The thing he keeps calling the "reet" is the rete, (which simply means net in Latin). It should be pronounced ray-tay.

Change: Social distancing is not social, just distancing. Say no to psychological warfare doublethink.

come on nick, i've already had my share of negative today.

Ted proves Flat Earth.

a good TED presentation.. Finally!! but the commercial at the end about the traffic is the dumbest thing i have seen..They charge people to drive their cars!! WTF !! they scan their licence plates and send them a bill in the mail.. WTF !! because they are soo concerned about traffic and pollution. but billing people doesnt FIX A DAMN THING! are they putting their efforts into having clean electric, hydrogen,solars cars? NO they put their efforts into scanning people licence plates TO BILL THEM

I really wanted to be interested by this chat because I like this era of history, but it wasn't really interesting... Tom tried though.

Alexandre Astier

astrolabes are geocentric instruments

@fcouperin: Yeah, but I think that's something we should contemplate on our own, otherwise it would just be moralising. After all he said we gain something as well as loose something. It's plenty of stuff to occupy our minds with still. Also in the past, most people were really dumb, and just a few really smart people had to do all the progress for us! ...Probably while those average smart people, where just preoccupied with checking out the time :P A lot of work ,just to get on with your day.

It is a solution, how could you not see this? If there is a parking lot full of people that aren't entering a store the parking lot serves, then that's a problem. Imposing a fine to deter people from parking in said lot if they have no valid use in the lot is a solution. The same concept and proven to work here. A by-product of the fines was an increase in public transportation use, and car-pooling. Both of which save people more money than the fuel it takes to travel there separately.

@Vid That's an interesting device. But what was the mans point? Is he saying that were relying to heavily on technology? that were becoming dumb asses because everything is becoming automatic? We need to think more? Surely there was more to this, than 'lets all look at the pretty replica tool, that cost a few grand'?

1300 AC with one of these bad boys in your pocket to cheat on a math test

Is this guy on loan from Steve Jobs' harem? He has needlessly mentioned 3 Apple(tm) products. He says MacBook(tm) instead of "Laptop", and iPhone(tm) instead of "cell phone". What a tool.