Al-Ashraf Umar II

al‐Malik al‐Ashraf (Mumahhid al‐Dīn) ʿUmar ibn Yūsuf ibn ʿUmar ibn ʿAlī ibn Rasūl (born c. 1242, died 22 November 1296 in Yemen) was the third Rasulid sultan and a polymath.[2] He is known for writing the first description of the use of a magnetic compass for determining the qibla.[2] Also, his works on astronomy contain important information on earlier sources.[2]

al‐Malik al‐Ashraf
Al-Ashraf's diagram of the compass and Qibla, copied in Yemen, 1293.[1]
Borncirca 1242
Died22 November 1296
Yemen
Scientific career
FieldsAstronomy

In a treatise about astrolabes and sundials, al-Ashraf includes several paragraphs on the construction of a compass bowl (ṭāsa). He then uses the compass to determine the north point, the meridian (khaṭṭ niṣf al-nahār), and the Qibla towards Mecca. This is the first mention of a compass in a medieval Islamic scientific text and its earliest known use as a Qibla indicator, although al-Ashraf did not claim to be the first to use it for this purpose.[1][2]

Notes
  1. Schmidl, Petra G. (1996–97). "Two Early Arabic Sources On The Magnetic Compass". Journal of Arabic and Islamic Studies. 1: 81–132.CS1 maint: ref=harv (link) http://www.uib.no/jais/v001ht/01-081-132schmidl1.htm#_ftn4 Archived 2014-09-02 at the Wayback Machine
  2. Schmidl 2007.
gollark: <@!156021301654454272> Bug report! Your bot does `AttributeError: 'Bot' object has no attribute 'secret_password'` after I do `rocket sudo thingy`.
gollark: https://media.discordapp.net/attachments/426116061415342080/790994936279465984/IMG_20180524_213137.jpg
gollark: Just test it on 5 cases and assume it works.
gollark: Oh dear. They may have undergone a ⴭK-class event.
gollark: Did you know they have STILL harbinged barely any ☭?

References


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.