Emmanuel Liais (15 February 1826 – 5 March 1900) was a French

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

botanist Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

and

explorer Exploration is the process of exploring, an activity which has some Expectation (epistemic), expectation of Discovery (observation), discovery. Organised exploration is largely a human activity, but exploratory activity is common to most organis ...

who spent many years in

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. He was born in

Cherbourg Cherbourg is a former Communes of France, commune and Subprefectures in France, subprefecture located at the northern end of the Cotentin peninsula in the northwestern French departments of France, department of Manche. It was merged into the com ...

, the son of a wealthy family in the

shipbuilding Shipbuilding is the construction of ships and other Watercraft, floating vessels. In modern times, it normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation th ...

industry. He was an amateur

scientist A scientist is a person who Scientific method, researches to advance knowledge in an Branches of science, area of the natural sciences. In classical antiquity, there was no real ancient analog of a modern scientist. Instead, philosophers engag ...

and made some

meteorological Meteorology is the scientific study of the Earth's atmosphere and short-term atmospheric phenomena (i.e. weather), with a focus on weather forecasting. It has applications in the military, aviation, energy production, transport, agriculture ...

observations and wrote some papers. The astronomer

François Arago Dominique François Jean Arago (), known simply as François Arago (; Catalan: , ; 26 February 17862 October 1853), was a French mathematician, physicist, astronomer, freemason, supporter of the Carbonari revolutionaries and politician. Early l ...

took note of one of his papers written in 1852, which determined that the weather in his hometown was milder than that of

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...

. He then went to Paris in 1854 and worked at the

Paris Observatory The Paris Observatory (, ), a research institution of the Paris Sciences et Lettres University, is the foremost astronomical observatory of France, and one of the largest astronomical centres in the world. Its historic building is on the Left Ban ...

. There he assisted

Urbain Le Verrier Urbain Jean Joseph Le Verrier (; 11 March 1811 – 23 September 1877) was a French astronomer and mathematician who specialized in celestial mechanics and is best known for predicting the existence and position of Neptune using only mathematics. ...

in creating a telegraphic meteorological network. He went to

to observe the

solar eclipse of September 7, 1858 A total solar eclipse occurred at the Moon's Lunar node, descending node of orbit on Tuesday, September 7, 1858, with a Magnitude of eclipse, magnitude of 1.0210. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby total ...

and ended up staying there for a long time. He became a close acquaintance of the Brazilian Emperor

Dom Pedro II ''Don (honorific), Dom'' PedroII (Pedro de Alcântara João Carlos Leopoldo Salvador Bibiano Francisco Xavier de Paula Leocádio Miguel Gabriel Rafael Gonzaga; 2 December 1825 – 5 December 1891), nicknamed the Magnanimous (), was the List o ...

, and became the director of the Imperial Observatory at

Rio de Janeiro Rio de Janeiro, or simply Rio, is the capital of the Rio de Janeiro (state), state of Rio de Janeiro. It is the List of cities in Brazil by population, second-most-populous city in Brazil (after São Paulo) and the Largest cities in the America ...

from January to July 1871 and again from 1874 to 1881. Although the observatory had been founded in 1827, in reality it was occupied mostly with teaching students of military schools. Liais reorganized it to concentrate on research. He discovered the

comet A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing. This produces an extended, gravitationally unbound atmosphere or Coma (cometary), coma surrounding ...

C/1860 D1 (Liais). This was his only comet discovery and the first comet discovered in Brazil. He made astronomical observations of

Mars Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmosph ...

and in 1865 speculated that the dark

albedo feature In planetary geology, an albedo feature is a large area on the surface of a planet (or other Solar System body) which shows a contrast in brightness or darkness (albedo) with adjacent areas. Historically, albedo features were the first (and usu ...

s were vegetation and not water (in fact, as we know today, they are neither). At the behest of the emperor, he made extensive exploration expeditions within Brazil and studied the plants of remote regions, sending some of them to France. He wrote a book entitled ''Climats, géologie, faune et géographie botanique du Brésil'' (Paris: Garnier Frères, 1872). In 1878 a public dispute developed between him and Manoel Pereira Reis and his position at the observatory gradually became untenable. At the beginning of 1881 he resigned and returned to his hometown of Cherbourg. He was mayor of Cherbourg from 1884–1886 and again from 1892 until his death in 1900. He imported exotic plants from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

to Cherbourg. He married a Dutch woman, Margaritha Trovwen, and they had no children. He bequeathed his property, located in a magnificent botanical park, to the city of Cherbourg. It is now known as the Emmanuel Liais Gardens. A

crater A crater is a landform consisting of a hole or depression (geology), depression on a planetary surface, usually caused either by an object hitting the surface, or by geological activity on the planet. A crater has classically been described ...

on Mars is named after him. In addition to the park named after him, there is also "Emmanuel Liais" street in Cherbourg.

References

External links

City of Cherbourg: brief biographical info

Polemic between Liais and some Brazilian astronomers
(in Portuguese)
Meteorology and biographical information

Observatório Nacional - 175 years of service
(in Portuguese) {{DEFAULTSORT:Liais, Emmanuel 1826 births 1900 deaths People from Cherbourg-Octeville 19th-century French astronomers 19th-century French explorers 19th-century French botanists Botanists with author abbreviations Botanists active in South America French emigrants to Brazil