When was the Ulugh Beg Observatory built?
The foundation of the Ulugh Beg Observatory was laid in the earlier half of the 1420s, and the observatory was completed around 1428. It was built by the Timurid astronomer and ruler Ulugh Beg in Samarkand.
Questions about Ulugh Beg Observatory
Short answers, pulled from the story.
Why was part of the Ulugh Beg Observatory sextant built underground?
The Fakhri sextant had a radius of 40.04 meters, making it the largest astronomical instrument in the world at the time. Building the full structure above ground would have made the building dangerously tall, so part of the sextant was sunk into a ditch roughly 2 meters wide cut into the earth.
What is the Zij-i Sultani and when was it published?
The Zij-i Sultani is an astronomical table and star catalogue published by Ulugh Beg in 1437. It listed around 1,000 stars, was written in Persian, and was the first star catalogue published since Ptolemy's Almagest. It remained in use until the 19th century.
How accurate was Ulugh Beg's measurement of the tropical year?
Ulugh Beg calculated the length of the tropical year as 365 days, 5 hours, 49 minutes, and 15 seconds, an error of only plus 25 seconds. This was more accurate than Nicolaus Copernicus's later estimate, which had an error of plus 30 seconds.
Who destroyed the Ulugh Beg Observatory and when?
The observatory was destroyed around 1449 following the assassination of Ulugh Beg by his son, Abd al-Latif. The killing drove dozens of astronomers and mathematicians out of Samarkand and led to the collapse of the institution.
Who rediscovered the remains of the Ulugh Beg Observatory?
The Russian archaeologist Vassily Vyatkin uncovered the remains of the Ulugh Beg Observatory in 1908. What survives today is the foundations and the buried portion of the marble quadrant.