6 ms·

Astrolabe: Shipwreck find 'earliest navigation tool'

48 points by Thevet 9y ago

LiamMcCalloway 9y ago
I spent last Sunday's lunch explaining to my girlfriend the revolution that being able to compute your longitude was (I could not help myself). There were prizes offered by the trading companies and governments to whomever would devise a reliable way to determine one's longitude. Conceptually, it's interesting that longitude is mostly useful only if you know your latitude (that's because 1degre of change in longitude does not translate to the same distance traveled whether you're at the equator or at the pole.)
- rimliu 9y ago
  Just get her a copy of this: https://www.amazon.com/Longitude-Genius-Greatest-Scientific-Problem/dp/080271529X https://www.amazon.com/Longitude-Genius-Greatest-Scientific-... :)
  - zazen 9y ago
    How's GP going to make himself look smart by regurgitating one of the most successful pop history books of the 90s, if he hooks her up with the book directly? I hope my cynicism is misplaced and GP has a genuine passion for 18th century maritime history. But most people I meet who "can't help" spewing out random facts are more r/iamverysmart than actual enthusiasts.
    - pavlov 9y ago
      It's storytelling. You can't possibly be expected to have genuine passion for the art and science behind every interesting story in the world... Otherwise the only stories that get told will be PhD dissertations.
      - zazen 9y ago
        Your friends must be better story tellers than mine! Second-hand stories tend to be pretty stale in my experience. Bad enough when people try to tell about something they heard happened to Joe, worse when they try to tell about something technical that happened centuries ago. Stories like the Longitude story can be told outside academic dissertations - by people like Dava Sobel, though, not really by Fred who's just read her book.
        pavlov 9y ago
        Not everyone is a great storyteller... But when someone starts off with: "Here's something really interesting I read the other day, let me try share it with you" -- isn't it kind to listen and engage?
        zazen 9y ago
        I guess I was seeing a big distinction between telling your friends _about_ this great book you've read, and telling the story yourself, as if you were the expert, as if you, rather than the author, had done the research and formed the narrative. I got the impression that LiamMcCalloway had done the latter, because he said he "explained" to his gf about longitude (and doesn't mention the book at all). If you start to "explain" to people on the basis of having read one book, that's being a know-it-all. Yes, this is an uncharitable reading of LiamMcCalloway's post, but I don't think I quite pulled it out of thin air. LiamMcCalloway, if I've got you wrong and you are in fact an intellectually honest person, I apologize without reservation! If I don't make any more replies, it's because some people who don't like the tone of my original post are taking the opportunity to downvote everything I say.
        RingwormOne 9y ago
        So you're saying that no lay person can share interesting facts during casual conversation? You must be an expert on something to casually talk about it at lunch? Nonsense. This is one of the sillier things I've ever read on HN.
        9y ago
yoodenvranx 9y ago
Slightly Offtopic: If you are interested in how similar devices might have been made 100s and 1000s of years ago you should check out the latest videos on the Clickspring Youtube Channel [1]. Chris is building a copy of the Antikythera mechanism (mostly) without using modern tools and he is doing a stellar job. The quality of his videos and his attention to detail is _amazing_! If you are into this kind of stuff you will most likely end up binge watching his whole channel over the weekend. [1] https://www.youtube.com/channel/UCworsKCR-Sx6R6-BnIjS2MA https://www.youtube.com/channel/UCworsKCR-Sx6R6-BnIjS2MA
- moftz 9y ago
  I see him using a mill and lathe multiple times. He even uses a CNC at least once in part 5. All the machinery he uses would have been something available to a machinist in the 50s. He's not using a plasma cutter but he's using relatively modern tools that an ancient greek bronzesmith couldn't even dream of.
  - yoodenvranx 9y ago
    That's why I wrote "... (mostly) ..." ;) I think he just uses the Mill and the CNC to speed things up, but some parts (like the gears) he does completeley by hand with a file even though he could do it way faster and more precise on a mill.
zazen 9y ago
To clarify the headline: this is the earliest astrolabe _for maritime use_ _yet found_, dating to AD 1495-1502. Astrolabes in general go back to classical times. I guess the headline is getting at that distinction with the phrase "navigation tool", but it didn't become clear to me until I read TFA.
- johnlbevan2 9y ago
  It's not a great headline given many navigational tools vastly predate this. E.g. the (arguably) most obvious maritime navigational tool being the compass: https://en.wikipedia.org/wiki/History_of_the_compass#Early_navigational_compass https://en.wikipedia.org/wiki/History_of_the_compass#Early_n... > The compass was used in Song Dynasty China by the military for navigational orienteering by 1040–44,[15][28][29] and was used for maritime navigation by 1111 to 1117
- abrowne 9y ago
  The whole article has some issues: https://thonyc.wordpress.com/2017/10/24/getting-names-right-is-rather-important-in-the-history-of-science/ https://thonyc.wordpress.com/2017/10/24/getting-names-right-...
  - LeifCarrotson 9y ago
    Please don't just link to your blog instead of making a comment here. At the very least, summarize your post and link to the extrapolation. "This is specifically a marine astrolabe for determining latitude from the elevation of a specific star, not a generic astrolabe with many other functions. It's also not the earliest navigational tool. These names and distinctions are important, and getting them wrong is indicative of damaging, incorrect click-bait journalism. I go into more detail on my blog: [link]"
    - abrowne 9y ago
      Yes, I should have summarized, but it's not my blog, just one I read. So I was just being lazy, posting as I went out through door to work, not trying to get clicks on my site or something.
gshubert17 9y ago
Geoffrey Chaucer wrote perhaps the earliest technical manual about 1391, on the astrolabe. http://www.chirurgeon.org/files/Chaucer.pdf http://www.chirurgeon.org/files/Chaucer.pdf
- MaysonL 9y ago
  Nasir al-Din al-Tusi (18 February 1201 – 26 June 1274) wrote one earlier. From the Wikipedia article about him, a couple of his works: al-Risalah al-Asturlabiyah – A Treatise on the astrolabe. Zij-i Ilkhani (Ilkhanic Tables) – A major astronomical treatise, completed in 1272. https://en.wikipedia.org/wiki/Nasir_al-Din_al-Tusi https://en.wikipedia.org/wiki/Nasir_al-Din_al-Tusi
jcrei 9y ago
The Portuguese first sailed and reached India in 1498 (Vasco da Gama). This ship (nau in Portuguese) left Lisbon in 1502. It was part of the second voyage of exploration from Portugal to India.
LeifCarrotson 9y ago
On a shipwreck, huh? That's an interesting place to find a new and effective navigational tool. The boat carrying it should, in theory, be less likely to become a shipwreck. I wonder where else we can apply this observation? In the use of ECC memory, maybe? Or when analyzing web analytics, perhaps: if your site traffic only shows a small percentage of mobile users, you might choose not to optimize for mobile browsers. But instead there could be a problem with the source of your observation: Just like the archaeologists who discovered this marine astrolabe aren't observing both successful and unsuccessful sailors at that time in history, you're looking at the subset which has shown up on and used your site, and who have analytics enabled. It could be that mobile users aren't showing up in your "shipwrecks" because they're quickly bouncing from your difficult-to-use site or because their search engine can see that your site isn't optimized and it doesn't recommend you to them.
- roywiggins 9y ago
  > The boat carrying it should, in theory, be less likely to become a shipwreck. Alternatively, only a few boats would have had one, and the ones that did were using them to strike out further afield than their less well-equipped contemporaries. Since they could be more confident about their location, they could venture further from land and might get caught by storms more easily.
- sosborn 9y ago
  > The boat carrying it should, in theory, be less likely to become a shipwreck. The sea is a cruel mistress. Ships regularly get wiped out despite state-of-the-art navigation. I would suspect that the vast majority of shipwrecks throughout mankind's history has little do with navigation and everything to do with the inherent danger of the open ocean.

48 points by Thevet 9y ago

I spent last Sunday's lunch explaining to my girlfriend the revolution that being able to compute your longitude was (I could not help myself). There were prizes offered by the trading companies and governments to whomever would devise a reliable way to determine one's longitude. Conceptually, it's interesting that longitude is mostly useful only if you know your latitude (that's because 1degre of change in longitude does not translate to the same distance traveled whether you're at the equator or at the pole.)

rimliu 9y ago
Just get her a copy of this: https://www.amazon.com/Longitude-Genius-Greatest-Scientific-Problem/dp/080271529X https://www.amazon.com/Longitude-Genius-Greatest-Scientific-... :)
- zazen 9y ago
  How's GP going to make himself look smart by regurgitating one of the most successful pop history books of the 90s, if he hooks her up with the book directly? I hope my cynicism is misplaced and GP has a genuine passion for 18th century maritime history. But most people I meet who "can't help" spewing out random facts are more r/iamverysmart than actual enthusiasts.
  - pavlov 9y ago
    It's storytelling. You can't possibly be expected to have genuine passion for the art and science behind every interesting story in the world... Otherwise the only stories that get told will be PhD dissertations.
    - zazen 9y ago
      Your friends must be better story tellers than mine! Second-hand stories tend to be pretty stale in my experience. Bad enough when people try to tell about something they heard happened to Joe, worse when they try to tell about something technical that happened centuries ago. Stories like the Longitude story can be told outside academic dissertations - by people like Dava Sobel, though, not really by Fred who's just read her book.
      - pavlov 9y ago
        Not everyone is a great storyteller... But when someone starts off with: "Here's something really interesting I read the other day, let me try share it with you" -- isn't it kind to listen and engage?
        zazen 9y ago
        I guess I was seeing a big distinction between telling your friends _about_ this great book you've read, and telling the story yourself, as if you were the expert, as if you, rather than the author, had done the research and formed the narrative. I got the impression that LiamMcCalloway had done the latter, because he said he "explained" to his gf about longitude (and doesn't mention the book at all). If you start to "explain" to people on the basis of having read one book, that's being a know-it-all. Yes, this is an uncharitable reading of LiamMcCalloway's post, but I don't think I quite pulled it out of thin air. LiamMcCalloway, if I've got you wrong and you are in fact an intellectually honest person, I apologize without reservation! If I don't make any more replies, it's because some people who don't like the tone of my original post are taking the opportunity to downvote everything I say.
      - RingwormOne 9y ago
        So you're saying that no lay person can share interesting facts during casual conversation? You must be an expert on something to casually talk about it at lunch? Nonsense. This is one of the sillier things I've ever read on HN.
        9y ago

yoodenvranx 9y ago

Slightly Offtopic: If you are interested in how similar devices might have been made 100s and 1000s of years ago you should check out the latest videos on the Clickspring Youtube Channel [1]. Chris is building a copy of the Antikythera mechanism (mostly) without using modern tools and he is doing a stellar job. The quality of his videos and his attention to detail is _amazing_! If you are into this kind of stuff you will most likely end up binge watching his whole channel over the weekend. [1] https://www.youtube.com/channel/UCworsKCR-Sx6R6-BnIjS2MA https://www.youtube.com/channel/UCworsKCR-Sx6R6-BnIjS2MA

moftz 9y ago
I see him using a mill and lathe multiple times. He even uses a CNC at least once in part 5. All the machinery he uses would have been something available to a machinist in the 50s. He's not using a plasma cutter but he's using relatively modern tools that an ancient greek bronzesmith couldn't even dream of.
- yoodenvranx 9y ago
  That's why I wrote "... (mostly) ..." ;) I think he just uses the Mill and the CNC to speed things up, but some parts (like the gears) he does completeley by hand with a file even though he could do it way faster and more precise on a mill.

zazen 9y ago

To clarify the headline: this is the earliest astrolabe _for maritime use_ _yet found_, dating to AD 1495-1502. Astrolabes in general go back to classical times. I guess the headline is getting at that distinction with the phrase "navigation tool", but it didn't become clear to me until I read TFA.

johnlbevan2 9y ago
It's not a great headline given many navigational tools vastly predate this. E.g. the (arguably) most obvious maritime navigational tool being the compass: https://en.wikipedia.org/wiki/History_of_the_compass#Early_navigational_compass https://en.wikipedia.org/wiki/History_of_the_compass#Early_n... > The compass was used in Song Dynasty China by the military for navigational orienteering by 1040–44,[15][28][29] and was used for maritime navigation by 1111 to 1117
abrowne 9y ago
The whole article has some issues: https://thonyc.wordpress.com/2017/10/24/getting-names-right-is-rather-important-in-the-history-of-science/ https://thonyc.wordpress.com/2017/10/24/getting-names-right-...
- LeifCarrotson 9y ago
  Please don't just link to your blog instead of making a comment here. At the very least, summarize your post and link to the extrapolation. "This is specifically a marine astrolabe for determining latitude from the elevation of a specific star, not a generic astrolabe with many other functions. It's also not the earliest navigational tool. These names and distinctions are important, and getting them wrong is indicative of damaging, incorrect click-bait journalism. I go into more detail on my blog: [link]"
  - abrowne 9y ago
    Yes, I should have summarized, but it's not my blog, just one I read. So I was just being lazy, posting as I went out through door to work, not trying to get clicks on my site or something.

gshubert17 9y ago

Geoffrey Chaucer wrote perhaps the earliest technical manual about 1391, on the astrolabe. http://www.chirurgeon.org/files/Chaucer.pdf http://www.chirurgeon.org/files/Chaucer.pdf

MaysonL 9y ago
Nasir al-Din al-Tusi (18 February 1201 – 26 June 1274) wrote one earlier. From the Wikipedia article about him, a couple of his works: al-Risalah al-Asturlabiyah – A Treatise on the astrolabe. Zij-i Ilkhani (Ilkhanic Tables) – A major astronomical treatise, completed in 1272. https://en.wikipedia.org/wiki/Nasir_al-Din_al-Tusi https://en.wikipedia.org/wiki/Nasir_al-Din_al-Tusi

jcrei 9y ago

The Portuguese first sailed and reached India in 1498 (Vasco da Gama). This ship (nau in Portuguese) left Lisbon in 1502. It was part of the second voyage of exploration from Portugal to India.

LeifCarrotson 9y ago

On a shipwreck, huh? That's an interesting place to find a new and effective navigational tool. The boat carrying it should, in theory, be less likely to become a shipwreck. I wonder where else we can apply this observation? In the use of ECC memory, maybe? Or when analyzing web analytics, perhaps: if your site traffic only shows a small percentage of mobile users, you might choose not to optimize for mobile browsers. But instead there could be a problem with the source of your observation: Just like the archaeologists who discovered this marine astrolabe aren't observing both successful and unsuccessful sailors at that time in history, you're looking at the subset which has shown up on and used your site, and who have analytics enabled. It could be that mobile users aren't showing up in your "shipwrecks" because they're quickly bouncing from your difficult-to-use site or because their search engine can see that your site isn't optimized and it doesn't recommend you to them.

roywiggins 9y ago
> The boat carrying it should, in theory, be less likely to become a shipwreck. Alternatively, only a few boats would have had one, and the ones that did were using them to strike out further afield than their less well-equipped contemporaries. Since they could be more confident about their location, they could venture further from land and might get caught by storms more easily.
sosborn 9y ago
> The boat carrying it should, in theory, be less likely to become a shipwreck. The sea is a cruel mistress. Ships regularly get wiped out despite state-of-the-art navigation. I would suspect that the vast majority of shipwrecks throughout mankind's history has little do with navigation and everything to do with the inherent danger of the open ocean.