Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: May 29, 2025
The appearance of the new star in 1572 led him to form a catalogue of 777 stars, vastly superior in accuracy to those of Hipparchus and Ulugh Beig. His improvements on the lunar theory were still more valuable. He discovered the important inequality called the variation, and also the annual inequality which depends on the position of the earth in its orbit.
Too near the limb for observation. LAVOISIER. A small bright walled-plain N. of Ulugh Beigh. It has a somewhat dark interior. West of it is Lavoisier A, a ring-plain about 14 miles in diameter. Both are too near the limb for useful observation. GERARD. A large enclosure close to the limb, still farther N., containing a long ridge and a crater.
Meanwhile the Moors were leaders of science in the west, and Arzachel of Toledo improved the solar tables very much. Ulugh Begh, grandson of the great Tamerlane the Tartar, built a fine observatory at Samarcand in the fifteenth century, and made a great catalogue of stars, the first since the time of Hipparchus. Nicolai Copernicus, a Sclav, was born in 1473 at Thorn, in Polish Prussia.
This was favorably compared by them with the harsh behavior of their suzerains, the Taidshut princes, and two of their chiefs, named Ulugh Bahadur and Thugai Talu, with many of the tribe went to join Temudjin. They were shortly after attacked and dispersed by the Taidshuts. This alarmed or disgusted several of the latter's allies, who went over to the party of Temudjin.
Here was prepared his great star catalogue, based upon the earlier observations of Hipparchus, and destined to remain alone in its field for more than twelve centuries, until Ulugh Bey, Prince of Samarcand, repeated the work of his Greek predecessor.
LICHTENBERG. A conspicuous little ring-plain, about 12 miles in diameter, in an isolated position on the Mare, some distance N. of Briggs. It was here that Madler records having occasionally noticed a pale reddish tint, which, though often searched for, has not been subsequently seen. ULUGH BEIGH. A good-sized ring-plain, E. of the last, with a bright border and central mountain.
He re-edited the star-catalogues of Ptolemy, Ulugh Beigh, Tycho Brahe, Hevelius, Halley, Flamsteed, Lacaille, and Mayer; calculated the eclipse of Thales and the eclipse of Agathocles, and vindicated the memory of the first Astronomer Royal. But he was no less active in meeting present needs than in revising past performances.
The Moors in Spain did their share of the work carried on by their Eastern co-religionists, and the first independent star catalogue since the time of Hipparchus was made by another Oriental, Tamerlane's grandson, Ulugh Begh, who built a fine observatory at Samarcand in the fifteenth century.
Word Of The Day
Others Looking