Heinrich Christian Schumacher, a Danish astronomer, born at Bramstedt, Holstein, Sept. 3, 1780, died Dec. 28, 1850. He was educated at Kiel, Jena, Copenhagen, and Göttingen, resided from 1807 to 1810 in Altona, and in 1810 became extraordinary professor in the university of Copenhagen. In 1813 he became superintendent of the observatory at Mannheim, and in 1815 ordinary professor of astronomy and superintendent of the observatory at Copenhagen. In 1816 he was employed to measure the territory of Hamburg, and in 1817 to measure the degrees of latitude from Lauenburg to Skagen, and the degrees of longitude from Copenhagen to the W. coast of Jutland. In 1821 he received the direction of the survey and mapping of Holstein and Lauenburg, and from that time lived in Altona. In 1824, in connection with the English board of longitude, he determined the difference of longitude between the observatories of Greenwich and Altona; and in 1830 he made at the castle of Güldenstein the observations in regard to the length of the seconds pendulum which served as the base of the Danish scale of measures. In 1822 he published accurate accounts of the distances of Venus, Jupiter, Mars, and Saturn from tile moon.

In 1821 he began his Astro-nomische Nachrichten, which is still continued; and in conjunction with other astronomers, especially Bessel, he undertook at Stuttgart in 1836 the editing of an Astronomisches Jahr-buch. - His nephew Christian Andreas, born Sept. 6, 1810, has published a course of lectures on astronomy, and a Danish translation of Humboldt's Kosmos (1847), and since 1848 has edited at Copenhagen the scientific and industrial journal Nordlyset.