| Dictionary, Encyclopedia and Thesaurus - The Free Dictionary 1,756,733,651 visitors served. |
|
Dictionary/ thesaurus | Medical dictionary | Legal dictionary | Financial dictionary | Acronyms | Idioms | Encyclopedia | Wikipedia encyclopedia | ? |
Al-Battani |
0.01 sec. |
|
Al-Battani (äl-bät-tä`nē) or Albatenius (ăl'bətē`nēəs), b. before 858, d. 929, Arab astronomer and mathematician. He is best known in astronomy for his improvements and corrections of the Ptolemaic tradition. His Kitab al-Zij, which in Latin translation was very influential in the Middle Ages and the Renaissance, contains an elaborate set of astronomical tables and discusses a wide range of practical problems in spherical astronomy, some of which were devised for the purpose of solving related astrological problems. He recognized the possibility of an annular eclipse of the sun and obtained the very accurate value of 23°35' for the obliquity of the ecliptic. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
|
| ? Mentioned in | ? References in periodicals archive | |
|---|---|---|
Now the astronomical works of, say,
al-Khwarizmi (Indian and Sasanian influence) and al-Battani (Greek
influence), and the mathematical works of the same al-Khwarizmi
(essentially Babylonian algebra and Indian arithmetic), were
particularly influential in Europe, regardless of the fact that they
were already out-dated and surpassed in the Islamic world. In
the ninth century, Iranian astronomer al-Battani discovered that for a
sundial to function properly, the needle must point toward Polaris
(North star). |
| Encyclopedia |
| Free Tools: |
For surfers:
Free toolbar & extensions |
Word of the Day |
Help
For webmasters: Free content | Linking | Lookup box | Double-click lookup | Partner with us |
|---|