What is this comet described by Muslim 1200 years ago?

[Haitham Hamdan]

* When the Abbaasee Khalifah: alMu’tasim was intending to invade Ammooriyah, a comet with a tale appeared in the heavens.

Fortune tellers considered this as bad luck and warned him against his plans.

But he did not take them seriously. He invaded Ammooriyah and was victorious.

Thereafter, the famous poet abuTammaam (died 228 AH) said:

The sward is more truthful than books … in its edge is the criterion between seriousness and play

Then he said:

People warned him (alMu'tasim) from a dark terrible situation … whenever the western planet with the tale appeared.

* Also, ibnulAtheer described in his history book a comet with a tale which appeared from the west year 222 AH.

* Also alMaqreezee and ibn Iyyaass sighted such a comet in their books.

Which comet was this?!

[Mahmoud Al-Misri]

Al Salamu Alaikum Shaykhi Al-Habib

I did a fast search and found the following:

1) Convert the hijri to gregorian: http://www.rabiah.com/convert/

222 H ~ 836 CE

2) From Wikipedia: http://en.wikipedia.org/wiki/1P/Halley#Early_appearances

837: In this year, it is calculated that Comet Halley may have passed as close as 0.03 AU (3.2 million miles) from Earth, by far its closest approach. Its tail may have stretched 90 degrees across the sky.

Seen every: 75-76 years (next predicted time - 2061)
http://en.wikipedia.org/wiki/Halley%27s_Comet

3) Here are two forums I used (that support this view) - smile:

ãÐäÈ åÇáí.. åá åæ "ÇáßæßÈ ÇáÛÑÈí Ðæ ÇáÐäÈ"!¿
http://www.safita1.com/vb/showthread.php?t=3737

and also post #3 here: http://www.allsc.info/vb/showthread.php?p=27527

4) Also they mention in wikipedia (http://en.wikipedia.org/wiki/Halley%27s_Comet#Orbit) that its orbit is Retrograde, and if I understand this properly it would imply that it came from the West.

And Allah knows best (smile)

[Haitham Hamdan]

Waalykum Assalam warahmatullah.
Subhaanallaah!
I thought it was Halley, but when I did my own calculations I did not get that year 222 AH would have been a year when Halley would have passed earth (the difference is not a multiple of 76)! I guess I made a mistake somewhere.

Jazakallahu khairan brother Mahmoud.