6 Fascinating Ways Our Ancestors Navigated the Oceans

People have been exploring the oceans since prehistoric times, way before they had GPS to help them figure out where they were. In this new episode of SciShow, Hank reveals 6 ingenious ways our ancestors navigated the oceans. Let's go!
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Sources:
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www.vos.noaa.gov/MWL/aug_08/na...
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ageofex.marinersmuseum.org/ind...
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www.livescience.com/27696-viki...
www.visiteskifjordur.is/icelan...
www.oceannavigator.com/January...
exploration.marinersmuseum.org...
www.nature.com/nature/journal/...
www.cultural-china.com/chinaWH...
afe.easia.columbia.edu/special...
nationalgeographic.org/encyclo...
hyperphysics.phy-astr.gsu.edu/...
www.astrolabes.org/pages/mari...
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www.pbs.org/weta/roughscience/...
www.timeanddate.com/astronomy...
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www.quora.com/Why-is-the-ligh...
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[@Jharrisimages]

I was a Navigator (Quartermaster) in the US Navy and we still train to shoot star/sun lines with sextants and use stars for navigation. One time, during deployment in 2010, we lost all power in the middle of the Indian Ocean for 3 days. During that time we calculated our position, speed, drift and heading using the stars and were accurate to within 10 yards of our actual position (we checked once the power came back up) so navigating by the stars still works as long as you have the right equipment and knowledge.

[@mehere8038]

What happens if you're in the southern hemisphere, where the north star is not visible? I've always wondered that

[@Jharrisimages]

@@mehere8038 There are 57 stars that are used for nautical/aeronautical navigation purposes. Polaris (the North Star) is one of the brightest in the Northern Hemisphere and it's position is relatively unchanging (it tends to hover over the North Pole year-round) which is why it has been used for navigation since the first mariners learned to use the stars. But, in the Southern Hemisphere the constellation Crux (or the Southern Cross) is used for a lot of the same reasons, there are two stars in the Southern Cross (Acrux and Gacrux) that can be used to draw a straight line through the South Pole. In celestial navigation you use the positions of three separate stars in the sky to triangulate a spot on Earth, by knowing your relative position to each of the stars and using a nautical almanac (basically a book that shows what the positions of celestial objects during the year are) a decent navigator can calculate their position fairly accurately.

[@santamulligan676]

Know your sidereal time , I made my own Davis quadrant

[@cringecasserole]

My grandfather was a B-52 Navigator and taught me how to use a Sextant. I don't remember how anymore haha. I can only imagine trying to shoot stars in turbulence.

[@cynthiamgrooms8195]

Thank you for your Service, for the Sacrifices only you know, & for this truly interesting comment!!! It’s truly remarkable that y’all were sooo close to the electronic calculation, & I have to wonder if you were actually the Correct one, as we’ve All seen that electronic intelligence, Isn’t always correct!!! I’ve Always believed that One should Never stop learning, & I’m known to verbally announce when I’ve learned something in a day! It’s something I started doing to demonstrate to my children, that I Didn’t/Don’t know Everything like they tend to believe, & to also show them that learning comes in Many forms, in Any situation, isn’t Just something that ends in school, & have since heard them doing the Same as Adults!!! I came to this video in Hopes of seeing a Beautiful brass instrument I’ve just come across, that’s being called a “Moon Compass”. I’m old now, but my youngest still always refers to the moon as”My Moon”, & was hoping it would be a nice thing for her to have, for thinking about “locating me”, when my time has ended here.

[@TheMCPvPTeam]

That moment when your name is Sam Schultz and it shows up on the screen and you're just a regular viewer. I had a mini heart attack XD

[@ShirinRose]

Sam Schultz 😂

[@TehFuzzyCoconut]

lol u should learn how to animate now

[@micahphilson]

Thanks for doing the animations for the show! I guess you must do them in your sleep, so you don't even know you're animating for the show. Or even an animator to begin with!

[@drdsouza5285]

LOL 😂 😂 😂

[@tee-sam-ee-red]

When?

[@LaceNWhisky]

"It's pretty hard to get lost these days..." Dude, I get lost in parking lots.

[@NyashaWutawunashe0]

"It's pretty hard to get lost these days..." Suuuure

[@adamstone897]

Nathan CFC Unless you're Sarah Bailin who does not know any Geography

[@ganaraminukshuk0]

The next day, Scishow posts a video on how 793 people got lost with no explanation as to how.

[@Kaalyn_HOW]

I'mma go with autocorrent not knowing who Sarah Palin is?

[@adamstone897]

OurPeanutGallerie Lols, Sarah Bails Out when a Salmon River run over Anchorage because the Crazy people are in Fairbanks not Anchor-age

[@schwarzerritter5724]

Nathan CFC People drive into rivers because their navigation apps tell them to.

[@SuperExodian]

that kamal thing is both genius and simple

[@gavinjones]

Fun fact: In arabic the word 'Kamal' has a similar meaning to Voila

[@ahmadalbaz6059]

"Kamal" is an arabic word means "perfection"

[@edgemadefoxe367]

Kamal just means "finished" or "complete" And if you say "kammal" it becomes a verb in it's imperative form It doesn't mean perfection nor voila

[@webbot15]

Many of these ways to navigate involve Polaris. It'd be cool to see an episode on how they re-kerjiggered for travel in the southern hemisphere.

[@gregorykhvatsky7668]

Everything that is based on the Sun works exactly the same. If you need to use stars, then 1), there is Sigma Octantis, but it's barely visible. If you are able to see it, it works just the same as Polaris. or 2) you can also fiddle with imaginary lines based on the Southern Cross to approximate the celestial pole. Or you can just use the compass ;-)

[@daemonicanfamilyschannelof9253]

They mostly used the Southern Cross. Two nations have the Southern Cross on their flags, even.

[@megaloblabber2948]

@@daemonicanfamilyschannelof9253 3 actually, Australia, New Zealand, and Brazil Edit: Its actually 5, as Samoa and Papua New Guinea also use it on their flags

[@Volundur9567]

Southern Cross

[@blitzwaffe]

I once heard that Arab explorers were great at navigating because they were used to navigating deserts (oceans of sand that also lack landmarks and show stars), which is a similar scenario to oceans of water.

[@wiiehsan123]

LagiNaLangAko23 yeah they did use it for that, they translate many Greek and Roman books into Arabic so they would have been using before European

[@amartinez97]

Suppose they would use that as a reference point.

[@dynamicworlds1]

While I can't say there's no truth to that, the arab world was, for a time, a center for learning and innovation. They were inventing algebra and the 0 with only Byzantium (who was mostly working off of old Roman knowledge), and China really doing solid academic work besides them. Combine this with the amount of trade flowing through the middle east, and navigation inventions would be expected.

[@byAresfx]

DynamicWorlds not true, India invented it

[@TheMasonX23]

Sandcastle • We call them "Arabic Numerals" and often falsely attribute 0 to them not because they invented them, but because during their Golden Age of science, they made them widespread enough for them to reach Europe. Also, "Algorithm" comes from an Arabic word, and most of the stars have Arabic names because of this period. Neil deGrasse Tyson gave a great talk on the subject. Oh, and base 60 was the Babylonians

[@only20frickinletters]

Nice work, Sam Schultz!

[@cyrilio]

17inchcorkscrew +

[@zvign7554]

17inchcorkscrew +

[@culwin]

Animations on fleek

[@sophiaruizuvalle2523]

+

[@phantasm1234]

Hi there, SciShow! I would love for people to learn about the terrifying and sudden nature of cerebral aneurysms! I had one rupture at 19 and I think it would make for an interesting video topic!

[@PhoenixRevealed]

That'll teach you not to do so many drugs. Seriously though, glad you survived it.

[@nicolebuck197]

phantasm1234 maybe if you gave them some money or if one of the patrons of this show decided to ask for you? i have seen you ask a lot. now im curious about it too

[@phantasm1234]

It really is so sudden... I was just finishing a workout off campus when the greatest pain I could imagine flooded my head.

[@Astrostevo]

Those Marshallese islanders stick charts. Whoah. Yup. Impressive! (Plus so much more here too.)

[@1QU1CK1]

Some viking families had crystals that were natural polaroid lenses that turned dark when held up to the sun even when it was cloudy out. This allowed them to navigate quite brilliantly for the times. The stones were usually kept a secret and passed down from generation to generation.

[@tnwhiskey68]

Well they blew the secret when they showed it on their show on the history channel. Damn Vikings!

[@GenaTrius]

I remember reading about sunstones, and I seem to recall that in at least one of the stories that talk about it, the sunstone *isn't even the magical thing.* Something like, there was someone looking for a really good navigator, who asked "who among you can tell me where the sun is?" on a really cloudy day. Someone pointed at a spot of sky, and the person looking said "fetch the sunstone to check if this person is right!" And the sunstone said they were, meaning they were a legendary navigator.

[@Luboman411]

Wow, the kamal is the epitome of smart simplicity. It's also crazy ingenious. It's these little inventions that make me look in awe at our ancestors--there were some quite smart cookies among them!

[@FlyKiwi]

A lot of Pacific and Oceanic imagery features a constelation called the Southern Cross and the Two Pointers (all of our flags for example) The Southern Cross is a diamond shaped formation that can be used to navigate because they are laid out in a similar fashion to the compass (though, of course it's use pre-dates physical compasses).

[@mehere8038]

not really like a compass layout. To navigate with the Southern Cross, you draw an imaginary line from the top star to teh bottom & continue down towards the horizon. You draw a second imaginary line through the middle of the pointers, travelling at right angles to them, again downwards. Where those 2 imaginary lines meet, follow it straight down to the horizon & that's south

[@FlyKiwi]

@@mehere8038 Yes I am aware but I adapted my explanation to assume most people have no knowledge of the Southern Cross, but most people DO understand the concept of a compass.

[@agustinaguero8163]

I remember watching Ragnar using a Sunstone in Vikings and I was waiting to see if Hank would mention it. I love this channel

[@oOoKaylaGirloOo]

Agustin Aguero OMG SAME!!! I was like "oh crap I hope he mentions the sun stone and the Vikings!!"

[@SophiaAstatine]

Solsteeeennnn

[@AndorianBlues]

stick charts are so cool. Supposedly experienced Marshallese sailors could close their eyes and literally feel each of the distinct currents and the directions they were coming from as the waves hit the ship.

[@stolas666]

Great Episode! Idea for a next episode: The history of sailboat rigs throughout the ages. Why they became popular and why we mostly use a sloop rig nowadays.

[@normanhosford2506]

Before radiation belts, James Van Allen was a WWII junior officer on a destroyer testing improved proximity fuses, junior enough (and not part of ships crew) so the location somewhere in the South Pacific was secret from him. He used a protractor and plumbob to measure the sun's elevation every minute for a half hour around local noon to determine maximum elevation angle and time. By fitting the measurements to a smooth curve, he was able to determine daily location to "about a mile". Ships location was secret but GMT was not. Source: U of Iowa General Astronomy class 1970, JVA digression from whatever the main topic of the lecture was.

[@nataliahellnah7582]

"Pretty hard to get lost today" I'm pretty sure your brother was looking for Alaska anyway, Hank...

[@Kodabearbear]

MOANA YOU KNOW WHERE YOU ARE

[@VicAusTaxiTruckie]

Just dont hi five the sky

[@meltossmedia]

jiunn wong that's the only way to know the way. also the stars are just soo shiny!

[@teriyama]

www.hokulea.com/worldwide-voyage/

[@renoni3885]

Dakota Mitchell no i don't. .

[@angeliesalvebernardez8587]

I came here for sea navigation.

[@barrykidwell7701]

I appreciate you, Sam

[@ganaraminukshuk0]

Number 6 takes the cake because it's based off of a myth that may turn out to be true.

[@Nerobyrne]

I was really surprised because I saw this on the show "Vikings" and I thought it was made up, like many things from popular movies are. I'm really glad to see it explained and that such a cool natural tool is actually real.

[@xidarian]

I love the idea of it, I imagine it would have been a carefully guarded secret if they where the only ones who knew how to use it.

[@AudrinaOralay]

Thank you very much for including the sun stones! I'm glad once again to support you on patreon. Informative episode, as always!

[@InfansDeAter]

Thank you, SciShow and patreons!

[@sassulusmagnus]

Amazing stuff. We sometimes tend to dismiss ancients as technologically backward and superstitious, but they were also very intelligent and resourceful. Those are some pretty clever and simple navigational strategies. Hats off.

[@JohnJohnson-jr6hp]

Getting lost is still possible. Crowds, thick woods, somewhere like a really big natural park.

[@kennethsizer6217]

In some ways, getting lost is even easier: All we modern folk need is a dead battery or wet cell phone and we're screwed.

[@Biosquid239]

thanks Sam for the animations!

[@kirknorman2403]

Very cool. Primitive means: have to be smarter with what you have. You should check out the Viking sun compass also!

[@MrMysticphantom]

@Scishow this was one of my favorite scishow eps nice job guys

[@andreaquadrati]

Oh, neat. This time I didn't have to wait a notification, found this right away. Always nice to be early on scishow

[@lampekartoffel]

"because... ofcourse they had magic stones" 😂 I'm so proud of the legacy of my ancestors 😂 I once read an article that Danish historians think Vikings could tell where they were on sea based on the marine life as well as tasting the seafloor

[@janglestick]

been talking about this stuff for a long time, thanks so much for providing ways to source the actual information. Have you heard that similar data is encoded in the complex carvings, sometimes of intersecting snakes, on artifacts and masts, and seemingly extraneously complicated knots found in the boats and possessions of ancient scandinavian sailors?

[@nylonsteel]

Hundreds of years old technology and I'm still to dumb/confused to use it lol.

[@IamMissPronounced]

*too _pats your back_

[@DavidDylanFisher]

Birds. Some sea birds range as far as 200 miles from land before returning to shore to roose, so by keeping track of sea birds, you can if there's an island nearby, even if you can't see it.

[@hamstsorkxxor]

They also learned what birds could be seen at what distance from land. Say you see an albatross? Land is quite possibly quite some distance away, although you know there is land "nearby". Say you see an eagle? You should probably make sure to keep at least four eyes constant on the horizon and not sail at night, least you run aground. So yes, they did use birds to navigate.

[@diegojames8678]

I love the idea of using the environment to give yourself directions. It’s so clever

[@ZexMaxwell]

thanks for putting up the Sources. I'm really interested in the sunstone and will look into it more.

[@Looking4LPs]

Sam Schultz is the real mvp

[@joelcrow]

Man you guys are answering all of my crazy questions....love your science topics!

[@YuriRadavchuk]

I'd like to add on the first story about Oceania people. Linguists found that some tribes have an absolute terms for directions, so they don't even say left right etc.. but North and South. This ability is trained from birth and it helps to navigate world dramatically. Just try to remember what direction you're heading to without looking at any device.

[@ZennExile]

We all pretend that knowledge of the stars is somehow impressive the farther back you go in time. But when there is no light pollution, the stars are not a collection of billions of single points, but masses of swirling paint with fixed objects moving through it. What they did was memorize that single episode of the cartoon they watched in the sky before bed until they knew all the words and were singing along with the intro music. There was literally nothing else to do because night was a thing people suffered from.

[@Master_Therion]

Interesting comment, very erudite and poetic. ^_^ Reminds me of something I heard about the night sky being the television of their day, and each constellation was a story.

[@ZennExile]

how do you know stupid fuckpotato? OH YEAH you don't. AND THE KEY FUCKING PART OF THE MESSAGE WAS "WITHOUT LIGHT POLLUTION" you fucking moron...

[@Acheron538]

Very well said.

[@Antworkk]

I mean, light pollution is stopping us from seeing the stars... kind of its thing, you know?

[@hypersapien]

Great episode! Would love to see a similar one about how different cultures made different kinds of maps (Similar to the stick chart you showed)

[@mehere8038]

Australian Aboriginal cultures used the stars as maps. They found star combinations that could be told into a story, showing directions to travel to get from place to place. Many Australian roads today actually look like various constellations if you copy just their intersections onto a piece of paper, cause the roads were built along existing Aboriginal tracks that were using star maps to navigate the land

[@thezman350]

Really enjoyed this episode and great motion graphics!

[@TygerTigerable]

Always a pleasure to watch an episode of Sci-Show! Regarding possible future content, considering current U.S. government attitudes towards coal and the EPA, I would love to see Sci-Show do an episode on the pollution-weather incidents like the Great Smog of London c1952 or the 1948 Donora smog. Curious to know if such conditions could be met again if clean air laws were to be repealed versus current production technology.

[@Dichtsau]

WOW this episode was SO SO GOOD!

[@PhoenixRevealed]

How could you produce a video about pre-GPS navigation and not include the sextant?

[@TomClarke1995]

Martin Green As a professional merchant mariner, I can tell you that a sextant is simply a later adaptation of an astrolabe for measuring angles. Only, you actually have to visibly see the horizon. It’s not as interesting as a sunstone or groundbreaking as the magnetic compass.

[@productionpenguin4974]

This show is better than watching regular TV.

[@andresparramar]

Amazing! Thank you soo much! :)

[@Master_Therion]

What! You didn't mention everyone's favorite navigation tool... the sextant. The lack of sextant in my life is very frustrating :(

[@ELYESSS]

My favorite navigation tool is internet explorer

[@truedarkness4052]

Why are there sextants around my anus?

[@Master_Therion]

TheRedKnight Nah, I'd prefer they keep their "Jolly Rogering" to themselves. (that's a pun, I can explain it if you want)

[@Master_Therion]

ILYES Oh hi! again ;)

[@spicymeat4477]

The good old days of looking for "sex" in the dictionary.

[@WhereWhoMe]

Thanks for adding the awesome animation, Sam!!

[@andreeliasoliveira]

Amazing content, I've always wanted to know this stuff!

[@flamencoprof]

The older I get the more respect I have for my ancestors, and the less I accept woo-woo explanations for their achievements.

[@RestlessHarp]

Fascinating, thank you!

[@isaac5771]

Good job with the video Sam!

[@s3renity274]

This is the best to fall asleep to. You should do sleep time stories.

[@dance4life812]

I loved the subject of this vid! Keep it up Scishow❤

[@JosephHuddleston]

These all help with latitude. How about an episode on the struggle to figure out longitude. A great book, Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time, is a great read for anyone interested.

[@SanctuaryReintegrate]

I navigate by pure intuition. The only place I ever end up is the fridge, but it WORKS.

[@stephanvandenadel4647]

Congrats on + 4 mill subs... On to 10 mill!

[@johnclavis]

Terrific episode!

[@GabeLucario]

I love that Hank is back now :D

[@poo_toot]

I love learning old tech like those,, they really make you use your brain..

[@EDITHFIVE]

You forgot the European perfection of the timepiece so that on the ocean 'when' was a big help in finding 'where'.

[@ragnkja]

Combining it with the compass and a latitude-finding device like a kamal, cross-staff or sextant gives you a pretty accurate way to find out exactly where you are.

[@SSLk13]

This was awsome!!!

[@isabelleobryon5583]

Thanks Sam Schultz!! The animation was fantastic!!

[@benjaminbuljevic7977]

very interesting and useful video, i like it!

[@MehreenHassan225]

Man this channel is the best

[@Slavir_Nabru]

With your arm outstretched, count how many fists you can lay on top of each other between the horizon and Polaris (which you can find by following the big dipper/plow), each fist is roughly 10 degrees of latitude. No need to waste your time making these fancy string and block of wood contraptions. You can also identify East by tracing the path of the first star to rise of Orion's belt, it rises within 1 degree of East unlike the sun which can be off by a fair margin depending on season.

[@dellsantiago8108]

Slavir Nabru ty

[@xsDelyia]

Roughly ain't gonna cut it crossing oceans

[@varana]

Calling a small wooden board with a string attached "fancy contraption" does stretch the term a bit. Unless you think hand-axes are marvels of technology. :D

[@sophiaruizuvalle2523]

And its probably not a good idea to get some 5 crew members to put their hands on your arm, pretty sure they all have some other ship sailing to do

[@FrakCylon]

Amazing video!!

[@9000leo]

You missing out the most genious tool - the clock! for longitudes! The museum at Greenwich has the whole story of why a clock that works on sea is so useful yet hard to design, but then people made it!

[@lilj4818]

Getting lost is super easy where I live. Too many trees and mountains. Good luck finding cell service! And we have zero places with free wifi in my county. Plus GPS is incredibly unhelpful even when you do have service. We have dozens of truckers that get sent down the shortest path to the interstate, but GPS doesn't tell them that the one lane tunnel is only 9 feet tall. They have to back up for a couple of miles before they can even turn around, unless they cut into people's yards.

[@ALSmith-zz4yy]

GPS does not use cellular phone system.

[@Sebach82]

Ok, this was a cool episode. Almost enough to make up for "biomale." And smooth animations, Sam!

[@Agent00abe]

Pretty great video. Keep it up!

[@nishbrown]

Awesome work, Sam!

[@Mummele]

that was an awesome episode

[@shavono8402]

GOOD JOB SAM (the animations looked cool)

[@IAmTheAce5]

1:23 (singsong) AWE AWE!! We're explorers reading every sign...

[@user-lp3ew1xb5u]

Really interesting video!

[@mikeissweet]

love the animations!

[@Apostate_ofmind]

this is AMAZING

[@Ariranhaa]

The stick device is neat.

[@RandomPerson-br4jh]

I "sea" what you did there

[@silver12561]

Random Person iam "shore" u did

[@ashboon1625]

Wosh! So shore-king!!!

[@AlbertaGeek]

Because you're up on "current" affairs.

[@DarKnightofCydonia]

Can't get over how incredibly genius the Kamal is

[@harjuny.wiranata7856]

My ancestor were sailors. It makes me proud

[@yourikhan4425]

Particularly interesting video.

[@TheWraithkrown]

Was I the only one that had to look up CE? Why use CE when AD has been the convention for so long? Maybe they teach CE in schools now? Thanks for the video, and the opportunity to learn an additional fact:)

[@BVN-TEXAS]

TheWraithkrown it's about political correctness now.

[@WolfJustWolf]

The vikings also used a solar compass. A disk with a cone in the middle. Using the direction of the shadow the cone casts , you can find North. Using the length of the shadow at noon , you can work out the latitude.

[@funkydunky1430]

the only problem was to find out when the noon occured

[@nerine9301]

Interesting! Thanks.😊

[@realityrealized8370]

Great video.

[@stvp68]

People are so amazingly smart!

[@user-ii1rk4ui7k]

I have seasickness so I'm in a predicament. Thanks Scishow for the reminder.

[@smokefire3]

I always did wonder if any civilisation used the way the oceans feel to navigate but then i shrugged it off thinking you would need to be really amazing to pick up the feeling of currents and such on boats, then watching this It makes sense to do so if your in a canoe a small vessel that is going to feel those difference's clearly, so yeah thats pretty amazing.

[@Larweigan]

They bring this up in an episode of QI, apparently some navigators would get into the water and use their breasts/scrotum to feel the movement of the water.

[@narrotibi]

Thanks for using CE and BCE!

[@ianrupenthal2206]

Thanks Sam, you did great.

[@hongkongernobody9174]

Interesting. Thanks.

[@Darkstar.....]

Thats cool. The kamal i see the navigator nami uses an unusual navigator compass which is upgraded. The first compass gets you to the next island and no where else. The next compass nami has allows her 3 islands to sail to. Same as the kamals one port design and multiple knot design for multiple ports.

[@whitepony8443]

Oh gosh, thanks GPS for making our life easier.

[@SunriseFireberry]

Another way was the marvellously creative invention: the chronometer, again long before GPS.

[@JohnDoe-qx3zs]

And the basis of GPS! Each GPS satellite is a flying chronometer which broadcasts the time of day and it's own position. By comparing 3 signals, a ship can calculate her own position. Airplanes and landcrabs need a 4th signal to correct for not being at sea level.

[@pancreasnostalgia]

The Bishop Museum in Oahu had an exhibit about Pacific Islander navigation when I went there in January.

[@kuryamtl]

the stick chart is totally awesome.

[@joejohns3543]

Good stuff.