Asimov was born (officially) January 2, 1920, in the town of Petrovichi (pronounced peh-TRUV-ih-chee), then in the Russian Soviet Federated Socialist Republic (czarist Russia no longer existed, while the USSR hadn't formed yet) and now in Russia. It can be found at latitude 53°58' N, longitude 32°10' E, about 400 km. southwest of Moscow and some 16 km east of the border between Belarus and Russia. Born to Jews in the early days of the RSFSR, there are no accurate records, however, and it is possible that he may have been born as early as October 4, 1919.
Asimov's birthdate was temporarily changed by his mother to September 7, 1919 in order to get him into school a year earlier. When, several years later, he discovered this, he insisted that the official records be changed back. January 2, 1920 was the date he personally celebrated throughout his life.
His family left the Soviet Union on January 11, 1923 and arrived in New York City February 3.
Please note that the date given on the first page of Asimov's third autobiographical book, I. Asimov: A Memoir, is a typographical error (January 1, 1920). Asimov's other books leave no possible doubt that the date he celebrated as his birthday was January 2.
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