Number 2 - Abu Rayhan al-Biruni

Al-Biruni was born near Kath in Khwarizm (now a part of Uzbekistan) on Sept. 4, 973. His teacher in astronomy and mathematics was initially the eminent Abu Nasr Mansur, a member of the family then ruling at Kath but, in 995, the attack on the ruler of Khwarizm by the ruler of Jurjaniya briefly drove al-Biruni into exile.

In 997 al-Biruni returned to Kath, where he observed a lunar eclipse that Abu al-Wafa observed in Baghdad; on the basis of the time difference they determined the longitudinal difference between the two cities, one of the few instances in which this method is known to have been used.

During the next few years al-Biruni paid many visits to the Samanid court at Bukhara, as well as the court of the Ispahbad of Gilan and busily collected an enormous mass of information on the chronology of the ancient nations of Europe and Asia that he dedicated to the Ziyarid prince of Gurgan in 1000 and that, in English, is known simply as the Chronology. This remains the most significant source for the various Iranian calendars and for much of the history of central Asia.

By 1004 al-Biruni was in Jurjaniya, where he came to prominence and was employed both as a diplomat and as a spokesman for the throne. He continued, however, making his astronomical observations under the Shah's patronage.

But, in 1017, the Shah’s brother-in-law, Mahmud, conquered Khwarizm and carried off al-Biruni as a prize of war. Al-Biruni was then sent to the region near Kabul, where he commenced making observations in 1018.

Most of his extant works were written in the 1020s and 1030s and reflect his interest in, and growing knowledge of, the Sanskrit astronomical texts current in the Punjab that he discovered on his trips to India during this time.

Until his death soon after 1050 in Afghanistan, al-Biruni continued to write, turning his attention to problems of specific gravity, gemology, pharmacology, and Indian philosophy (the Patanjali), among other subjects. It is not clear when he wrote the Tafhim, his most important work on astrology. In all, the bibliography he himself drew up lists 113 titles.

To call al-Biruni merely a physicist somewhat belittles his extraordinary scientific achievements but, as one of the first people to concoct and adhere to a rigid scientific method, it is only right that his name go down in the list of Most Famous Physicists…