Category Archives: Astronomy

Yemeni citing of 1006 CE Supernova

Interpretation of the historic Yemeni reports of supernova SN 1006: early discovery in mid-April 1006 ?

Ralph Neuhaeuser (U Jena), Dagmar Neuhaeuser, Wafiq Rada (Hila), Jesse Chapman (U Stanford), Daniela Luge (U Jena), Paul Kunitzsch (U Munich)

The recently published Yemeni observing report about SN 1006 from al-Yamani clearly gives AD 1006 Apr 17±2 (mid-Rajab 396h) as first observation date. Since this is about 1.5 weeks earlier than the otherwise earliest reports (Apr 28 or 30) as discussed so far, we were motivated to investigate an early sighting in more depth. We searched for additional evidences from other areas like East Asia and Europe. We found that the date given by al-Yamani is fully consistent with other evidence, including: (a) SN 1006 “rose several times half an hour after sunset” (al-Yamani), which is correct for the location of Sana in Yemen for the time around Apr 17, but it would not be correct for late Apr or early May; (b) the date (3rd year, 3rd lunar month, 28th day wuzi, Ichidai Yoki) for an observation of a guest star in Japan is inconsistent (there is no day wuzi in that lunar month), but may be dated to Apr 16 by reading wuwu date rather than a wuzi date; (c) there is observational evidence that SN 1006 was observed in East Asia early or mid April; for the second half of April, a bad weather (early monsoon) period is not unlikely — there is a lack of night reports; (d) the observer in St. Gallen reported to have seen SN 1006 “for three months”, which must have ended at the very latest on AD 1006 Jul 10, given his northern location, so that his observations probably started in April. We conclude that the correctly reported details give quite high confidence in the fully self-consistent report of al-Yamani, so that the early discovery date should be considered seriously.

Comments: 11 pages, 2 figures, 1 table (in press) in Astronomical Notes 2016
Subjects: History and Philosophy of Physics (physics.hist-ph); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:1607.02915 [physics.hist-ph]
(or arXiv:1607.02915v1 [physics.hist-ph] for this version)

Yemen’s Agricultural Marker Stars

 ansi
The Yemeni scholar Yahya al-Ansi

No scholar in Yemen has done more to document and explain the rich tradition of Yemen’s indigenous knowledge on the stars and agricultural seasons than Yahya al-Ansi.  In addition to several published volumes, he has also created charts of the 28 المعالم الزراعية (agricultural marker stars). He was instrumental in founding the Astronomical Society of Yemen, which has a Facebook page. One of his latest contributions is a chart explaining these stars with their scientific identification.  This can be found here or by going to the Facebook group site, which is worth surfing.

ansi1

AIYS is pleased to provide support for Yahya al-Ansi to continue his publishing work.

Facebook Yemen: الجمعية الفلكية اليمنية

aston

The Astronomical Society of Yemen has a Facebook site created by the distinguished scholar of Yemeni astronomy, Yahya Yahya al-Ansi.  Check it out at https://www.facebook.com/groups/AstronomicalSocietyofYemen/

أهلا وسهلا بك إلى الجمعية الفلكية باليمنية. مخصص لطرح ومنافشة انشطة الجمعية المختلفة … مخصص لطرح كافة الانشطة الفلكية عربيا وعالميا

الاستاذ يحيى يحيى العنسي