xxxxxThe French astronomer Nicolas Lacaille, having arrived at the Cape of Good Hope, South Africa, in 1750, spent the next two years determining the position of some 10,000 stars in the southern hemisphere. During his stay, he also named fourteen new constellations, made the first measurement of the arc of meridian in this hemisphere, and, with the assistance of his fellow countryman Jérôme Lalande, arrived at a more accurate distance of the Earth from the Moon. His findings were published in his Catalogue of the Southern Sky in 1763.
NICOLAS LOUIS DE LACAILLE 1713 -
(AN, G1, G2, G3a)
Lacaille: artist unknown, contained in Atlas of the Messier Objects: Highlights of the Deep Sky, published in 2008, the work of Ronald Stoyan, a German journalist specializing in astronomy. Mayer: date and artist unknown. Wright: detail, mezzotint by the Irish artist Thomas Frye (1710-
xxxxxThe prominent French astronomer Nicolas Louis de Lacaille was born in Rumigny, near Rheims. He studied theology in Paris, but became interested in astronomy in 1737 and, over the next two years, took part in projects organised by the Academy of Sciences. He was appointed professor of mathematics at Mazarin College, Paris in 1739, and admitted to the Academy two years later.
xxxxxIn 1750 he led an expedition to the Cape of Good Hope, South Africa, and over the next two years determined the positions of some 10,000 stars of the southern hemisphere. And despite his limited equipment, he also catalogued a number of stars invisible to the naked eye, and named fourteen new constellations. Before leaving the Cape, he made the first measurement of the arc of meridian in the southern hemisphere and, given data provided by his fellow countryman and astronomer Jérôme Lalande, working in Berlin, he was able to provide a much more accurate measurement of the distance from the Earth to the Moon.
xxxxxAfter returning to France in 1754, he collated all his findings, and these were contained in his Coelum australe stelliferum, (Catalogue of the Southern Sky) published in 1763, the year after his death. These observations in the southern hemisphere were the first undertaken systematically since the visit of the English astronomer Edmund Halley to the island of St. Helena in 1677.
xxxxxIncidentally, Lacaille named one of the constellations he discovered Fornax Chemica (Chemical Furnace) in honour of the French chemist Antoine Lavoisier.
Johann Tobias Mayer
and Thomas Wright
xxxxxThe German astronomer Johann Tobias Mayer (1723-
xxxxxA German cartographer of this period who put his knowledge of astronomy to good use was Johann Tobias Mayer (1723-
xxxxxAs a cartographer he produced thirty maps of Germany, making ingenious use of astronomical data -
xxxxxIt was in 1750, the year Mayer produced his map of the moon, that the English astronomer Thomas Wright (1711-