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Al-Khujandi accurately computed the
axial tilt to be 23°32'19" (23.53°),[1] which was a significant improvement over the Greek estimate of 23°51'20" (23.86°)[2] and still very close to the modern measurement of 23°26' (23.44°).
This is wrong! The obliquity has not a constant value, but is decreasing with time. It was 23°51' at the time of Ptolemy and is actually 23°26'. Al-Khujandis value is only valid for his time!
Siffler (
talk)
18:55, 21 September 2008 (UTC)reply
Hey, obviously Khujandi cannot be from "the Mongol nobility" since the Mongols wouldn't be in the region for a couple hundred years!!! — Preceding
unsigned comment added by
76.181.83.193 (
talk)
23:47, 4 June 2012 (UTC)reply
References
^Richard P. Aulie (1994), "Al-Ghazali Contra Aristotle: An Unforeseen Overture to Science In Eleventh-Century Baghdad", PSCF45: 26-46 (
cf.References, 1001 Inventions)
"Al-Tusi says that al-Khujandi was one of the rulers of the Mongol tribe in that region so he must have come from the nobility." From
[1].
Wiqi(
55)00:57, 5 June 2012 (UTC)reply
Well, that website is considered reliable. We also don't second guess claims found in secondary/tertiery sources unless we have knowledge of the primary sources (Tusi's work doesn't seem accessible, though).
Wiqi(
55)01:20, 5 June 2012 (UTC)reply