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What is the origin of the name "astrolabe"? Is it in anyway related to "astro", stars, or is this just a coincidence? Nyh 10:53, 16 June 2007 (UTC)
- American Heritage Dictionary says: Middle English astrelabie, from Old French astrelabe, from Medieval Latin astrolabium, from Greek astrolabon, planisphere : astro-, astro- + lambanein, lab-, to take. — Sam 13:05, 16 June 2007 (UTC)
OBS:coincidence may be correct but may not be the reason for establishing the origin of the instrument only with reference to the name. There are many monemnet preserved in present-day Iran and Indean Which begged only on function, to study stars.
In addition, the Persian language IndoEuropean ice, which means many of the words may be found in most european languages
As you know the oldest Astrolabe funded from the area once called the Persian Empire. With Arabs take over the Persian the language had to suffer through a forced change. E.g. many Al-have been added in front of many names. Many words change shape because there is not enough letters in the Arabic language. In Arabic there is no letter P, every single word they come by change it either to F or B, In Arabic is not possible to say two consecutive consonants. Star pronounced therefore Estar or Astar and loop (loop= Circle, Circulate, means movement of stars) pronounced lobe.
I noticed that there was no mention of Arzachel, who perfected the astrolabe during the 11th century. There are two links verifying it on his page, and I also read about this from another source. Would it be alright to add a sentence or two about him on this page, in the appropriate setting (Medieval section)?
So, how is it possible that Greeks named an instrument that has been invented in Persian? Could it not be possible that Greeks who have been in contact with Persian have had to borrow the word? We know it's very common to borrow word, especially Loan from ruler’s language.
If I can prove that, I can prove even that the culture in a row with many other things that today are defined as Arabic is actually and originally is Persian. For instants KEMIA, this means rare in Indo-European language. But put a AL in front of it make it the known name AL-chime and its Arabic now. Why am I doing this? I think the right should be right. —Preceding unsigned comment added by 220.127.116.11 (talk) 08:52, 27 January 2010 (UTC)
I wanted to confirm that astrolabes were once used to locate Makkah (Mecca) and I had to do a separate search to accomplish this. I think it might be helpful to add a link from the Astrolabe page to the Makkah page. Perhaps more precisely, it would link to the Qibla article, which does have a link to the Astrolabe article. I also noticed that there seems to be a discrepency in the spelling of qibah. ~~Donna, 15 June 2005
- You are very welcome to include this information in the article itself. Sounds very interesting, sort of remiding of the way that the Chinese used compass for religious purpose as well. Thank you ! Rama 08:21, 16 Jun 2005 (UTC)
Does the astrolabe help locate a precise position or just the latitude of the observer? It's my understanding that it does not give longitude of the observer, and I believe this should be stated in the article, and a reference to the longitude article included. Also, perhaps a brief discussion of the fact that two coordinates are needed to locate one's position on the surface of the earth, and that knowing one's latitude alone is not sufficient to know one's location. Thank you! Dmp717200 (talk) 16:21, 21 October 2009 (UTC)dmp717200
Invention of metal astrolabe
I'm not convinced metal astrolabes were unknown before the 15th century. I was struck in the museum of history of science in Oxford by a beautiful example from around 950, somewhere in the Islamic world. However, I don't have the details to hand... if I can find them, I'll make the change. UncleKensson 21:53, 9 October 2005 (UTC) UncleKensson
- Yes, the SOAS website has the oldest known dated brass astrolabe, some 500 years before Zacuto's. I'll change the text accordingly. UncleKensson 22:29, 9 October 2005 (UTC)UncleKensson
- The link to SOAS's astrolabe is now broken. A quick search did not reveal a replacement link. --Lboges (talk) 20:17, 29 August 2012 (UTC)
I found this page very interesting but hard to understand, you should make it clearer I still don't understand how an astrolabe works! ~ Summer Eldemire Jamaica
I was here! I'm going to fix these faulty references, unless someone else is faster. Said: Rursus 05:34, 23 April 2007 (UTC)
- Did some, more needed – the loose unnumbered references in References should be associated with a certain text position, when possible, and then moved there, to become surrounded by <ref>...blarefbla...</ref>. Said: Rursus 05:42, 23 April 2007 (UTC)
Astrolabe vs sextant.
I question the accuracy of the second sentence of this article. The astrolabe was certainly an instrument that was well known and fairly well used in many parts of the old world and the orient (in the original sense), but it has never seemed to me to be a legitimate navigational instrument at sea. The Mariner's Astrolabe was developed in the late 15th c., but that is not the same as an astrolabe. It is a round, open-framed brass instrument with an alidade but lacking the planisphere and other components. The mariner's astrolabe was little used, though - only a few dozen are extant in collections today (G.L'E. Turner Antique Scientific Instruments. also see last paragraph here). The main instrument of navigation appears to be (from 1595) the John Davis (English explorer)'s Davis Quadrant, aka Backstaff - it was more accurate than the mariner's astrolabe and easier to use, especially for observations of the sun. The octant and later sextant replaced the Davis quadrant as far as I am aware.
The compass has an old history, dating in Europe to at least the 13th century. This time frame make the first statement a bit awkward.
It seems to me that a separate page for the mariner's astrolabe is required to eliminate some of the confusion.
Michael Daly 17:44, 21 August 2007 (UTC)
Mobile Astrolabe and Horologium
I have added a link to Mobile Astrolabe and Horologium. This link enables mobile and instant access to the astrolabe or horologium model of the universe from any point of earth with update each minute. Also the postions of planets and stars are given. It also explains on the background and ingenuity of these monumental models of the universe. chrsyl — Preceding unsigned comment added by Chrsyl (talk • contribs) 15:58, 26 March 2011 (UTC)
Computer generated astrolabe, ecliptic longitudes?
The computer generated astrolabe is otherwise very fine, and I am glad someone bothered to make it, but I think the markings of the zodiac (near the ecliptic) are a little bit ... well ... wrong.
Signs of zodiac are (at least in astrology) defined using _ecliptic_ longitudes, not rectascensions of the equator. Therefore the center of the signs of zodiac is the pole of the _ecliptic_, not the pole of the equator.
There are signs of zodiac on the computer generated astrolabe. And there are also coordinates. Fine. There is something wrong however. The lines separating the signs and the lines showing the coordinates obviously point to the celestial pole, that is the pole of the equator, the center of astrolabe. Methinks they should not.
Of course you can connect the pole of the equator to the ecliptic and separate arcs of 30 degrees ... but I don't thing they are either _ecliptic_ longitudes or the true borders of the signs of zodiac (of astrology).
Because of stereographic projection the pole of ecliptic is not at the center of the projected ecliptic, but it surely is away from the pole of the equator which is at the center.
Have I totally misunderstood what signs of zodiac are? Is there a different astronomical definition for them? Maybe so, but I find this construction "rectascension of the ecliptic plane" rather unusual on an astrolabe.
My source? Hmmm ... common sense ... basics of spherical astronomy found on just about any work worth reading
Yes I think you are right, there is a section in Van Cleempoel, Astrolabes at Greenwich (OUP 2005) which describes in detail how this error of laying out the ecliptic arises. Aparrently this is also an error found on some genuine antique astrolabes as well. Simonchadwick1023 (talk) 21:09, 8 November 2013 (UTC)
I seem to remember having once read about an astrolobe, and a search for it redirects here. Is that just an alternate spelling, and if so, shouldn't the article mention that? — Preceding unsigned comment added by 18.104.22.168 (talk) 03:46, 14 August 2012 (UTC)
I can find no citation any where for wooden astrolabes. this source is a really good one Lewis, M. J. T. (2001-04-23). Surveying Instruments of Greece and Rome. Cambridge University Press. ISBN 9780521792974. Retrieved 30 August 2012. and I plan to use it to improve the article. If some one else gets here first be bold J8079s (talk) 20:09, 30 August 2012 (UTC)