Joseph Jérôme Lefrançois de Lalande (; 11 July 1732 – 4 April 1807) was a French

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

freemason Freemasonry or Masonry refers to fraternal organisations that trace their origins to the local guilds of stonemasons that, from the end of the 13th century, regulated the qualifications of stonemasons and their interaction with authorities ...

and writer.

Biography

Lalande was born at

Bourg-en-Bresse Bourg-en-Bresse (; frp, Bôrg) is the prefecture of the Ain department in the Auvergne-Rhône-Alpes region in Eastern France. Located northeast of Lyon, it is the capital of the ancient province of Bresse ( frp, Brêsse, links=no). In 2018, ...

(now in the

département In the administrative divisions of France, the department (french: département, ) is one of the three levels of government under the national level ("territorial collectivity, territorial collectivities"), between the regions of France, admin ...

Ain Ain (, ; frp, En) is a department in the Auvergne-Rhône-Alpes region in Eastern France. Named after the Ain river, it is bordered by the Saône and Rhône rivers. Ain is located on the country's eastern edge, on the Swiss border, where ...

) to Pierre Lefrançois and Marie‐Anne‐Gabrielle Monchinet. His parents sent him to Paris to study law, but as a result of lodging in the Hôtel Cluny, where Delisle had his observatory, he was drawn to astronomy, and became the zealous and favoured pupil of both Delisle and

Pierre Charles Le Monnier Pierre Charles Le Monnier (; 23 November 1715 – 3 April 1799) was a French astronomer. His name is sometimes given as Lemonnier. Biography Le Monnier was born in Paris, where his father Pierre (1675–1757), also an astronomer, was professor ...

. Having completed his legal studies, he was about to return to Bourg to practise as an advocate, when Lemonnier obtained permission to send him to

Berlin Berlin ( , ) is the capital and largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's most populous city, according to population within city limits. One of Germany's sixteen constitue ...

, to make observations on the lunar

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby objects ...

in concert with those of

Lacaille Abbé Nicolas-Louis de Lacaille (; 15 March 171321 March 1762), formerly sometimes spelled de la Caille, was a French astronomer and geodesist who named 14 out of the 88 constellations. From 1750 to 1754, he studied the sky at the Cape of Good ...

at the

Cape of Good Hope The Cape of Good Hope ( af, Kaap die Goeie Hoop ) ;''Kaap'' in isolation: pt, Cabo da Boa Esperança is a rocky headland on the Atlantic coast of the Cape Peninsula in South Africa. A common misconception is that the Cape of Good Hope is t ...

Quarter of circle of Jonathan Sisson-MGR Lyon-IMG 9912

The successful execution of this task obtained for him, before he was twenty-one, admission to the Academy of Berlin, as well as his election as an adjunct astronomer to the

French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV of France, Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific me ...

. He now devoted himself to the improvement of the planetary theory, publishing in 1759 corrected edition of

Edmond Halley Edmond (or Edmund) Halley (; – ) was an English astronomer, mathematician and physicist. He was the second Astronomer Royal in Britain, succeeding John Flamsteed in 1720. From an observatory he constructed on Saint Helena in 1676–77, H ...

's tables, with a history of

Halley's Comet Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 75–79 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and thus the o ...

whose return in that year he had helped

Alexis Clairaut Alexis Claude Clairaut (; 13 May 1713 – 17 May 1765) was a French mathematician, astronomer, and geophysicist. He was a prominent Newtonian whose work helped to establish the validity of the principles and results that Sir Isaac Newton had ou ...

and

Nicole-Reine Lepaute Nicole-Reine Lepaute () née Étable de la Brière, also erroneously known as Hortense Lepaute, (5 January 1723 – 6 December 1788) was a French astronomer and human computer. Lepaute along with Alexis Clairaut and Jérôme Lalande calculated t ...

to calculate. In 1762 Delisle resigned the chair of astronomy in the Collège de France in Lalande's favour. The duties were discharged by Lalande for forty-six years. His house became an astronomical seminary, and amongst his pupils were

Delambre Jean Baptiste Joseph, chevalier Delambre (19 September 1749 – 19 August 1822) was a French mathematician, astronomer, historian of astronomy, and geodesist. He was also director of the Paris Observatory, and author of well-known books on th ...

Giuseppe Piazzi Giuseppe Piazzi ( , ; 16 July 1746 – 22 July 1826) was an Italian Catholic priest of the Theatine order, mathematician, and astronomer. He established an observatory at Palermo, now the '' Osservatorio Astronomico di Palermo – Giuseppe S ...

Pierre Méchain Pierre François André Méchain (; 16 August 1744 – 20 September 1804) was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep-sky objects and comets. Life Pierre Méchain was born i ...

, and his own nephew Michel Lalande. By his publications in connection with the

transit of Venus frameless, upright=0.5 A transit of Venus across the Sun takes place when the planet Venus passes directly between the Sun and a superior planet, becoming visible against (and hence obscuring a small portion of) the solar disk. During a trans ...

of 1769 he won great fame. However, his difficult personality lost him some popularity. In 1766, Lalande, with Helvetius, founded the "Les Sciences" lodge in Paris, and received its recognition from Grand Orient de France in 1772. In 1776, he changed its name to Les Neuf Soeurs, and arranged for

Benjamin Franklin Benjamin Franklin ( April 17, 1790) was an American polymath who was active as a writer, scientist, inventor, statesman, diplomat, printer, publisher, and political philosopher. Encyclopædia Britannica, Wood, 2021 Among the leading inte ...

to be chosen as the first worshipful master.Une loge maçonnique d'avant 1789: la R. L. Les neuf sœurs (Louis Amiable – ed. Baillière, 1897) Although his investigations were conducted with diligence rather than genius, Lalande's career was an eminent one. As a lecturer and writer he helped popularise astronomy. His planetary tables, into which he introduced corrections for mutual perturbations, were the best available up to the end of the 18th century. In 1801, he endowed the

Lalande Prize The Lalande Prize (French: ''Prix Lalande'' also known as Lalande Medal) was an award for scientific advances in astronomy, given from 1802 until 1970 by the French Academy of Sciences. The prize was endowed by astronomer Jérôme Lalande in 180 ...

, administered by the

, for advances in astronomy. Pierre-Antoine Véron, the young astronomer who for the first time in history determined the size of the Pacific Ocean from east to west, was Lalande's disciple. Lalande was an atheist, and wrote a dictionary of atheists with supplements that appeared in print posthumously. He never married but he had an illegitimate daughter

Marie-Jeanne de Lalande Marie-Jeanne-Amélie Le Francais de Lalande, born Marie-Jeanne Harlay (1768 – 8 November 1832), was a French astronomer and mathematician. Biography Lalande married her father's young cousin, also an astronomer, Michel Lefrançois de Lalande ( ...

whom he trained in mathematics so that she could help him with his work.

Near discovery of Neptune

In February 1847

Sears C. Walker Sears Cook Walker (March 28, 1805 – January 30, 1853) was an American astronomer. Born at Wilmington, Massachusetts son of Benjamin Walker and Susanna Cook, he graduated from Harvard University in 1825, he was a teacher till 1835, was an ...

of the

US Naval Observatory United States Naval Observatory (USNO) is a scientific and military facility that produces geopositioning, navigation and timekeeping data for the United States Navy and the United States Department of Defense. Established in 1830 as the Depo ...

was searching historical records and surveys for possible prediscovery sightings of the planet

Neptune Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times ...

that had been discovered the year before. He found that observations made by Lalande's staff in 1795 were in the direction of Neptune's position in the sky at that time and that Neptune might appear in the observation records. On 8 May and again on 10 May 1795 a ''star'' was observed and recorded with uncertainty noted on its position with a colon, this notation could also indicate an observing error so it was not until the original records of the observatory were reviewed that it was established with certainty that the object was Neptune and the position error between the two nights was due to the planet's motion across the sky. The discovery of these records of Neptune's position in 1795 led to a better calculation of the planet's orbit.

Awards and recognition

Père-Lachaise - Division 4 - Lefrançais de Lalande 01

* In 1765, Lalande was elected a member of the

Royal Swedish Academy of Sciences The Royal Swedish Academy of Sciences ( sv, Kungliga Vetenskapsakademien) is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special ...

. * In 1781, he was elected a Foreign Honorary Member of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and ...

. * His name is one of the 72 names inscribed on the Eiffel Tower. * The crater Lalande on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

is named after him. * A high school in

is named after Lalande. This high school was awarded the

Médaille de la Résistance The Resistance Medal (french: Médaille de la Résistance) was a decoration bestowed by the French Committee of National Liberation, based in the United Kingdom, during World War II. It was established by a decree of General Charles de Gaulle on 9 ...

in recognition of the wartime conduct of its teachers and pupils, a unique case among all schools in France.

Notable works

His published include: *''Traité d'astronomie'' (1st Ed., 2 vols., 1764; 2nd Ed., 4 vols., 1771–1781; 3rd Ed., 3 vols., 1792) *''

Histoire céleste française ''Histoire céleste française'' (''French Celestial History'') is an astrometric star catalogue published in 1801 by the French astronomer Jérôme Lalande and his staff at the Paris Observatory. This star catalog consists of the locations and ...

'' (1801), giving the places of 47,390 stars *''Bibliographie astronomique'' (1803), with a history of astronomy from 1780 to 1802 *''Astronomie des dames'' (1785) *''Abrégé de navigation'' (1793)
''Voyage d'un françois en Italie''
(1769), a valuable record of his travel in 1765–1766.
''Journal d'un voyage en Angleterre''
(1763

He communicated more than one hundred and fifty papers to the

, edited the ''Connoissance de temps'' (1759–1774), and again (1794–1807), and wrote the concluding two volumes of the 2nd edition of Montucla's ''Histoire des mathématiques'' (1802).

Publications

* * *

Notes

References

* * * * * Attribution *

External links

* /commons.wikimedia.org/w/index.php?title=File:Astronomie,_Tome_Premier.pdf Tome premier de ''Traité d'astronomie'', de 1764
Abrégé de navigation (pdf)

Portrait of Jerome Lalande from the Lick Observatory Records Digital Archive, UC Santa Cruz Library's Digital CollectionsJoseph Jérôme Le Français de Lalande letters to Mme. Dupiery, MSS 530
a
L. Tom Perry Special Collections

Brigham Young University Brigham Young University (BYU, sometimes referred to colloquially as The Y) is a private research university in Provo, Utah. It was founded in 1875 by religious leader Brigham Young and is sponsored by the Church of Jesus Christ of Latter-day ...

Letters from baron de Franz Xaver von Zach to Joseph Jérôme Lefrançois de Lalande
(1792-1806) at th
digital library

Paris Observatory The Paris Observatory (french: Observatoire de Paris ), a research institution of the Paris Sciences et Lettres University, is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world. Its histor ...

{{DEFAULTSORT:Lalande, Jerome Lefrancais De 1732 births 1807 deaths Writers from Bourg-en-Bresse 18th-century French astronomers French atheists Members of the French Academy of Sciences Burials at Père Lachaise Cemetery Les Neuf Sœurs Members of the Prussian Academy of Sciences Members of the Royal Swedish Academy of Sciences Honorary members of the Saint Petersburg Academy of Sciences 19th-century French astronomers Fellows of the American Academy of Arts and Sciences Fellows of the Royal Society French Freemasons