We have a soft spot for history’s obscure astronomers… the proverbial lonely men on a mountaintop who measure the sky, catalog the stars, and remain humble and unknown despite their achievements. Let the mainstream media write about the big shots of astronomy: Hubble, Shapley, Hale, and so on. We focus on the little guys.
One of our favorites is the French astronomer Nicolas Louis de Lacaille. You’ve see his name mentioned many times in the pages of One-Minute Astronomer as the discoverer of several deep-sky objects, especially in the southern hemisphere. In the mid-18th century, in a time before Messier and the Herschels, the humble and diligent Lacaille cataloged more stars than all other astronomers of his era combined, and assigned names and places for southern constellations still in use today.
Born in 1713, the young Lacaille was left destitute by the death of his father. He turned to theological studies, earned the sponsorship of a nobleman, and completed his religious work with the title of Abbe. But his interest was consumed by science, so he obtained work as a geographer and cartographer. He surveyed the French coast and made precise measurements of longitude. His diligence earned him admission to the French Academy, and he secured a position as mathematics professor at Mazarin College, with a small observatory at his disposal.
Though he made many celestial measurements from northern France, the other half of the sky beckoned. In 1750, he implored the Academy to let him travel to South Africa to catalog the southern stars. They granted his wish. Lacaille set sail for Cape Town, before it was called Cape Town, and set up shop near the slopes of Table Mountain. In just one year, using an absurdly small 1/2-inch refractor, he measured the positions of 9,766 stars and logged 42 deep sky objects including 47 Tucanae, omega Centauri, and the eta Carinae nebula.
He also named 14 obscure southern constellations that have left many stargazers scratching their heads. Unlike the northern sky, there are no grand mythological names here; Lacaille lived in a time that admired the tools of science and reason. Hence the names of constellations such as..
• Antlia Pneumatica, the Air Pump
• Caelum, the Engraving Tool
• Circinus, the Geometer’s Compasses
• Fornax Chemica, the Chemist’s Furnace
• Horologium Oscillatorium, the Pendulum Clock
• Mons Mensae, Table Mountain
• Microscopium, the Microscope
• Norma et Regula, the Level and Square
• Octans, the Octant
• Pictor, the Painter’s Easel
• Pyxis Nautica, the Ship’s Compass
• Reticulum Rhomboidalis, the eyepiece reticle, and
• Sculptor, the Sculptor’s workshops;
You can see why, when an astronomer from Lick Observatory first saw the far-southern sky, he said it looked like somebody’s attic!
Alas, Lacaille did not live to see his southern catalog published. Upon returning to France, the modest astronomer was shocked to learn he had become relatively famous for his work in South Africa. (Scientists were like rock stars in those days). He returned to his professorship and continued to grind away at his measurements. He died in 1762, at the age of 49, from rigors associated with overwork.
According to his biographer David Evans, Lacaille “lived for science and nothing else”. He had few friends and displayed fewer emotions, and left no record of a private life or ambition or the search for recognition. He lived and died for the stars. And he let his work stand as his memorial.
In honor of his work, a 60-cm telescope at Reunion Island in the Indian Ocean will be named the La-Caille telescope.