François Jean Dominique Arago (February 26, 1786 – October 2, 1853) was a French mathematician, physicist, astronomer, and politician. Wikipedia does not have an article with this exact name. ... February 26 is the 57th day of the year in the Gregorian Calendar. ... 1786 was a common year starting on Sunday (see link for calendar). ... October 2nd is the 275th day (276th in leap years) of the year in the Gregorian Calendar, with 90 days remaining. ... 1853 was a common year starting on Saturday (see link for calendar). ... A mathematician is a person whose area of study and research is mathematics. ... The word physicist should not be confused with physician, which means medical doctor. ... An astronomer or astrophysicist is a scientist whose area of research is astronomy or astrophysics. ... A politician is an individual involved in politics. ...

Early life

Arago was born at Estagel, a small village near Perpignan, in the département of Pyrenees-Orientales, France. He was the eldest of four brothers. Jean (1788 - 1836) emigrated to North America and became a general in the Mexican army. Jacques Etienne Victor (1799 - 1855) took part in Louis de Freycinet's exploring voyage in the Uranie from as 1817 to 1821, and on his return to France devoted himself to his journalism and the drama. The fourth brother, Etienne Vincent de (1802 - 1892), is said to have collaborated with Honoré de Balzac in The Heiress of Birague, and from 1822 to 1847 wrote a great number of light dramatic pieces, mostly in collaboration. Showing decided military tastes François Arago was sent to the municipal college of Perpignan, where he began to study mathematics in preparation for the entrance examination of the polytechnic school. Within two years and a half he had mastered all the subjects prescribed for examination, and a great deal more, and, on going up for examination at Toulouse, he astounded his examiner by his knowledge of J. L. Lagrange. Towards the close of 1803 he entered the École Polytechnique, Paris, but apparently found the professors there incapable of imparting knowledge or maintaining discipline. The artillery service was his ambition, and in 1804, through the advice and recommendation of Simeon Poisson, he received the appointment of secretary to the Paris Observatory. He now became acquainted with Pierre-Simon Laplace, and through his influence was commissioned, with Jean Baptiste Biot, to complete the meridianal measurements which had been begun by J. B. J. Delambre, and interrupted since the death of P. F. A. Méchain in 1804). Arago and Biot left Paris in 1806 and began operations along the mountains of Spain. Biot returned to Paris after they had determined the latitude of Formentera, the southernmost point to which they were to carry the survey. Arago continued the work until 1809, his purpose being to measure a meridian arc in order to determine the exact length of a metre. Location within France Perpignan ( Catalan Perpinyà) is a commune and the préfecture (administrative capital city) of the Pyrénées-Orientales département in southern France, and was the capital of the former province of Roussillon (French Catalonia). ... The départements (or departments) are administrative units of France, roughly analogous to British counties and are now grouped into 22 metropolitan and four overseas régions. ... Pyrénées-Orientales (Eastern Pyrenees) is a département of southern France adjacent to the northern Spanish frontier and the Mediterranean Sea. ... 1788 was a leap year starting on Tuesday (see link for calendar). ... 1836 was a leap year starting on Friday (see link for calendar). ... World map showing location of North America A satellite composite image of North America North America is the third largest continent in area and in population after Eurasia and Africa. ... Jacques Arago, (1790-1855) a brother of François Arago, a littérateur and a traveller, author of a Voyage Round the World. Categories: People stubs ... 1799 was a common year starting on Tuesday (see link for calendar). ... 1855 was a common year starting on Monday (see link for calendar). ... Note that this entry should not to be confused with Charles Louis de Saulces de Freycinet (1828-1923), French Prime Minister Louis Claude de Saulses de Freycinet, (August 7, 1779 - August 18, 1842) was a French navigator. ... 1817 was a common year starting on Wednesday (see link for calendar). ... 1821 was a common year starting on Monday (see link for calendar). ... 1802 was a common year starting on Friday (see link for calendar). ... 1892 was a leap year starting on Friday (see link for calendar). ... Honoré de Balzac Honoré de Balzac (May 20, 1799 – August 18, 1850), was a French novelist. ... 1822 was a common year starting on Tuesday (see link for calendar). ... 1847 was a common year starting on Friday (see link for calendar). ... Location within France Perpignan ( Catalan Perpinyà) is a commune and the préfecture (administrative capital city) of the Pyrénées-Orientales département in southern France, and was the capital of the former province of Roussillon (French Catalonia). ... Wikibooks Wikiversity has more about this subject: School of Mathematics Wikiquote quotations related to: Mathematics Look up Mathematics in Wiktionary, the free dictionary Wikimedia Commons has more media related to: Mathematics Bogomolny, Alexander: Interactive Mathematics Miscellany and Puzzles. ... The Capitole, the 18th century city hall of Toulouse and best known landmark in the city; in the foreground is the Place du Capitole, a hub of urban life at the very center of the city Toulouse (pronounced in standard French, in local Toulouse accent) ( Occitan: Tolosa, pronounced ) is a... Joseph Louis Lagrange Joseph Louis Lagrange (January 25, 1736 – April 10, 1813) was an Italian mathematician and astronomer who later lived in France and Prussia. ... 1803 was a common year starting on Saturday (see link for calendar). ... The cadets of Polytechnique rushed to the defense of Paris against the foreign armies in 1814. ... The Eiffel Tower has become a symbol of Paris throughout the world. ... 1804 was a leap year starting on Sunday (see link for calendar). ... Simeon Poisson. ... The Paris Observatory (in French, Observatoire de Paris or Observatoire de Paris-Meudon) is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world. ... Pierre-Simon Laplace Pierre-Simon, Marquis de Laplace (March 23, 1749 – March 5, 1827) was a French mathematician and astronomer, the discoverer of the Laplace transform and Laplaces equation. ... Jean-Baptiste Biot Jean-Baptiste Biot (April 21, 1774, Paris – February 3, 1862, Paris) was a French physicist and mathematician who in the early 1800s studied the relationship between electrical current and magnetism (see Biot-Savart Law), as well as the polarisation of light passing through chemical solutions. ... Meridian is: Meridian (astronomy): an imaginary circle perpendicular to the horizon. ... Jean Baptiste Joseph Delambre (September 19, 1749 in Amiens – August 19, 1822 in Paris) was a French mathematician and astronomer. ... 1804 was a leap year starting on Sunday (see link for calendar). ... 1806 was a common year starting on Wednesday (see link for calendar). ... Formentera is the smallest and most southerly island of the Balearic Islands group; it is one of the two Illes Pitiüses, along with Ibiza. ... 1809 was a common year starting on Sunday (see link for calendar). ... The term arc may refer to: A part of a circles circumference (also called a circle segment). ... The metre (American spelling: meter), symbol: m, is the basic unit of distance (or of length, in the parlance of the physical sciences) in the International System of Units. ...

After Biot's departure, the political ferment caused by the entrance of the French into Spain extended to the Canary Islands, and the population suspected Arago's movements and his lighting of fires on the top of Mount Galatzo as the activities of a spy for the invading army. Their reaction was such that he was obliged to give himself up for imprisonment in the fortress of Bellver in June 1808. On July 28 he escaped from the island in a fishing-boat, and after adventurous voyage he reached Algiers on August 3. From there he obtained a passage in a vessel bound for Marseilles, but on August 16, just as the vessel was nearing Marseilles, it fell into the hands of a Spanish corsair. With the rest the crew, Arago was taken to Roses, and imprisoned first in a windmill, and afterwards in a fortress, until the town fell into the hands of the French, when the prisoners were transferred to Palamos. After three months' imprisonment they were released on the demand of the dey of Algiers, and again set sail for Marseilles on the November 28, but then within sight of their port they were driven back by a northerly wind to Bougie on the coast of Africa. Transport to Algiers by sea from this place would have occasioned a weary delay of three months; Arago, therefore, set out over land, guided by a Moslem priest, and reached it on Christmas Day. After six months in Algiers he once again, on the June 21, 1809, set sail for Marseilles, where he had to undergo a monotonous and inhospitable quarantine in the lazaretto, before his difficulties were over. The first letter he received, while in the lazaretto, was from Alexander von Humboldt; and this was the origin of a connection which, in Arago's words, lasted over forty years without a single cloud ever having troubled it. Canaries Capitals Las Palmas de Gran Canaria Santa Cruz de Tenerife Area  – Total  – % of Spain Ranked 13th  7 447 km²  1,5% Population  – Total (2003)  – % of Spain  – Density Ranked 8th  1 843 755  4,4%  247,58/km² Demonym  – English  – Spanish  Canary Islander  canario/a Statute of Autonomy August 16... Bellver Castle is a circular castle on a hill near Palma de Mallorca in the island of Majorca, Balearic Islands. ... 1808 was a leap year starting on Friday (see link for calendar). ... July 28 is the 209th day (210th in leap years) of the year in the Gregorian Calendar, with 156 days remaining. ... For other uses, see Algiers (disambiguation). ... August 3 is the 215th day of the year in the Gregorian Calendar (216th in leap years), with 150 days remaining. ... Marseilles redirects here. ... August 16 is the 228th day of the year (229th in leap years) in the Gregorian Calendar. ... Corsair can refer to: a pirate who used to operate in the Mediterranean Sea, see Corsair (pirate) a French airline, see: Corsair (airline) several aircraft of the US Navy: the O2U Corsair the F4U Corsair the A-7 Corsair II a kind of fireworks a poem, The Corsair, by Lord... For the flower, see rose. ... Palamós is a town in the Mediterranean Costa Brava, located in the comarca of Baix Empordà, in the province of Girona, Catalonia, Spain. ... The American Captain William Bainbridge paying tribute to the Dey, circa 1800. ... November 28 is the 332nd day (333rd on leap years) of the year in the Gregorian calendar. ... The name Bougie originally comes from France. ... A satellite composite image of Africa Africa is the worlds second-largest continent in both area and population, after Asia. ... Joseph and Mary with baby Jesus, at the first Christmas Christmas (literally, the Mass of Christ) is a holiday in the Christian calendar, usually observed on December 25, which celebrates the birth of Jesus. ... June 21 is the 172nd day of the year (173rd in leap years) in the Gregorian Calendar, with 193 days remaining. ... 1809 was a common year starting on Sunday (see link for calendar). ... A lazaretto or lazaret is a quarantine station for maritime travellers. ... Friedrich Heinrich Alexander, Baron von Humboldt, ( September 14, 1769, Berlin– May 6, 1859, Berlin), was a German naturalist and explorer, and the younger brother of the Prussian minister, philosopher and linguist Wilhelm von Humboldt. ...

Scientific work

Arago had succeeded in preserving the records of his survey; and his first act on his return home was to deposit them in the Bureau des Longitudes at Paris. As a reward for his adventurous conduct in the cause science, he was elected a member of the Academy of Sciences, at the remarkably early age of twenty-three, and before the close of 1809 he was chosen by the council of the polytechnic school to succeed Gaspard Monge in the chair of analytical geometry. At the same time he was named by the emperor one of the astronomers of the Royal Observatory, which was accordingly his residence till his death, and it was in this capacity that he delivered his remarkably successful series of popular lectures in astronomy, which were continued from 1812 to 1845. The Bureau des Longitudes is a French scientific institution, founded by decree of June 25, 1795 and charged with the improvement of nautical navigation, standardisation of time-keeping, geodesy and astronomical observation. ... The Eiffel Tower has become a symbol of Paris throughout the world. ... The French Academy of Sciences (Académie des sciences) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. ... Gaspard Monge. ... Analytic geometry, also called coordinate geometry and earlier referred to as Cartesian geometry, is the study of geometry using the principles of algebra. ... 1812 was a leap year starting on Wednesday (see link for calendar). ... 1845 was a common year starting on Wednesday (see link for calendar). ...

In 1816, along with Joseph Louis Gay-Lussac, he started the Annales de chemie et de physique, and in 1818 or 1819 he proceeded along with Biot to execute geodetic operations on the coasts of France, England and Scotland. They measured the length of the seconds-pendulum at Leith, Scotland, and in the Shetland Islands, the results of the observations being published in 1821, along with those made in Spain. Arago was elected a member of the Bureau des Longitudes immediately afterwards, and contributed to each of its Annuals, for about twenty-two years, important scientific notices on astronomy and meteorology and occasionally on civil engineering, as well as interesting memoirs of members of the Academy. 1816 was a leap year starting on Monday (see link for calendar). ... Joseph-Louis Gay-Lussac (December 6, 1778–May 10, 1850) was a French chemist and physicist. ... 1818 is a common year starting on Thursday. ... 1819 was a common year starting on Friday (see link for calendar). ... Former Royal Yacht Britannia is permanently moored at Leith harbour. ... Scotland (Scottish Gaelic: Alba) is a country in northwest Europe, occupying the northern third of the island of Great Britain. ... Shetland Islands The Shetland Islands (sometimes historically spelled Zetland, formerly Hjaltland) are one of 32 unitary council regions in Scotland and a Lieutenancy Area. ... 1821 was a common year starting on Monday (see link for calendar). ...

Arago's earliest physical researches were on the pressure of steam at different temperatures, and the velocity of sound, 1818 to 1822. His magnetic observations mostly took place from 1823 to 1826. He discovered what has been called rotatory magnetism, and the fact that most bodies could be magnetized; these discoveries were completed and explained by Michael Faraday. He warmly supported Jean-Augustin Fresnel's optical theories, and the two philosophers conducted together those experiments on the polarization of light which led to the inference that the vibrations of the luminiferous ether were transverse to the direction of motion, and that polarization consisted in a resolution of rectilinear motion into components at right angles to each other. The subsequent invention of the polariscope and discovery of rotatory polarization are due to Arago. The general idea of the experimental determination of the velocity of light in the manner subsequently effected by Hippolyte Fizeau and Leon Foucault was suggested by him in 1838, but his failing eyesight prevented his arranging the details or making the experiments. Pressure is the application of force to a surface, and the concentration of that force in a given area. ... In physical chemistry and in engineering, steam refers to vaporized water. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... This article is about velocity in physics. ... A schematic representation of auditory signaling Sound is vibration, as perceived by the sense of hearing. ... 1818 is a common year starting on Thursday. ... 1822 was a common year starting on Tuesday (see link for calendar). ... Magnetic lines of force of a bar magnet shown by iron filings on paper A magnet is an object that has a magnetic field. ... 1823 was a common year starting on Wednesday (see link for calendar). ... 1826 was a common year starting on Sunday (see link for calendar). ... Michael Faraday Michael Faraday (September 22, 1791 – August 25, 1867) was a British scientist (a physicist and chemist) who contributed significantly to the fields of electromagnetism and electrochemistry. ... Augustin Fresnel Augustin-Jean Fresnel (pronounced fray-NELL) (May 10, 1788 – July 14, 1827), was a French physicist who contributed significantly to the establishment of the wave theory of light and optics. ... See also list of optical topics. ... This article treats polarization in electrodynamics. ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye, or in a more general sense, any electromagnetic radiation in the range from infrared to ultraviolet. ... See Oscillator (disambiguation) for particular types of oscillation and oscillators. ... The luminiferous aether: it was hypothesised that the Earth moves through a medium of aether that carries light In the late 19th century the luminiferous aether (light-bearing aether), or ether, was a substance postulated to be the medium for the propagation of light. ... This article is about motion in physics. ... Armand Hippolyte Louis Fizeau Physicist Armand Hippolyte Louis Fizeau (September 23, 1819-1896), French physicist, was born in Paris. ... J. B. Léon Foucault Jean Bernard Léon Foucault (18 September 1819–11 February 1868) was a French physicist best known for the invention of the Foucault pendulum, a device demonstrating the effect of the Earths rotation. ... 1838 was a common year starting on Monday (see link for calendar). ...

Nearly all the mathematical work of the "French school" was done before the year 1830. They are the direct successors of the French writers who flourished at the beginning of the nineteenth century, and seem to have been out of touch with the great German mathematicians of the early part of it, on whose researches much of the best work of that century is based; they are thus placed here, though their writings are in some cases of a later date than those of Gauss, Abel and Jacobi. 1830 was a common year starting on Friday (see link for calendar). ... Johann Carl Friedrich Gauss Johann Carl Friedrich Gauss (Gauß) (April 30, 1777 - February 23, 1855) was a legendary German mathematician, astronomer and physicist with a very wide range of contributions; he is considered to be one of the greatest mathematicians of all time. ... Niels Henrik Abel (August 5, 1802–April 6, 1829), Norwegian mathematician, was born in Finnøy. ... Karl Gustav Jacob Jacobi (Potsdam December 10, 1804 - Berlin February 18, 1851), was not only a great German mathematician but also considered by many as the most inspiring teacher of his time (Bell, p. ...

Politics and legacy

In 1830, Arago, who always professed liberal opinions of the breme republican type, was elected a member of the chamber of deputies for the Pyrénées-Orientales département, and he employed his talents of eloquence and scientific knowledge in all questions connected with public education, the rewards of inventors, and the encouragement of the mechanical and practical sciences. Many the most creditable national enterprises, dating from this period, are due to his advocacy - such as the reward to Louis-Jacques Daguerre for the invention of photography, the grant for the publication of the works of Fermat and Laplace, the acquisition of the museum of Cluny, the development of railways and electric telegraphs, the improvement of the reneile. In 1830 also he was appointed director of the Observatory, and as a member of the chamber of deputies he was able to obtain grants of money for rebuilding it in part, and for the addition of magnificent instruments. In the same year, too, he was chosen perpetual secretary of the Academy of Sciences, the place of J. B. J. Fourier. Arago threw his whole soul into its service, and by his faculty of making friends he gained at once for it and for himself a world-wide reputation. As perpetual secretary it was his duty to pronounce historical éloges on deceased members; and for this duty his rapidity and facility of thought, and his happy piquancy of style, and his extensive knowledge peculiarly adapted him. In 1834 he again visited Scotland, to attend the meeting of the British Association at Edinburgh. From this time till 1848 he led a life of comparative quiet - although he continued to work within the Academy and the Observatory to produce a multitude of contributions to all departments of physical science - but on the fall of Louis-Philippe he left his laboratory to join the Provisional Government (February 24, 1848). He was entrusted with two important functions, that had never before been given to one person, viz. the ministry of marine and colonies (February 24, 1848 - May 11, 1848) and ministry of war (April 5, 1848 - May 11, 1848); in the former capacity he improved of rations in the navy and abolished flogging. He also abolished political oaths of all kinds, and, against an array of moneyed interests, succeeded in procuring the abolition of negro slavery in the French colonies. On May 10, 1848, he was elected a member of the Executive Power Commission, a governing body of the French Republic. He was made President of the Executive Power Commission (May 11, 1848) and served in this capacity as provisional head of state until June 24, 1848, when collective resignation of the Commission was submitted to the National Constituent Assembly. At the beginning of May 1852, when the government of Louis Napoleon required an oath of allegiance from all its functionaries, Arago peremptorily refused, and sent in his resignation of his post as astronomer at the Bureau des Longitudes. This, however, the prince president declined to accept, and made "an exception in favour of a savant whose works had thrown lustre on France, and whose existence the government would regret to embitter." 1830 was a common year starting on Friday (see link for calendar). ... Pyrénées-Orientales (Eastern Pyrenees) is a département of southern France adjacent to the northern Spanish frontier and the Mediterranean Sea. ... The départements (or departments) are administrative units of France, roughly analogous to British counties and are now grouped into 22 metropolitan and four overseas régions. ... Louis Daguerre Louis-Jacques-Mandé Daguerre (1787 - 1851) was the Basque artist and chemist who is recognized for his invention of the Daguerreotype process of photography. ... Lens and mounting of a large format camera Photography is the process of making pictures by means of the action of light. ... Jean Baptiste Joseph Fourier (March 21, 1768 - May 16, 1830) was a French mathematician and physicist who is best known for initiating the investigation of Fourier series and their application to problems of heat flow. ... The British Association or the British Association for the Advancement of Science or the BA is a learned society with the object of promoting science, directing general attention to scientific matters, and facilitating intercourse between scientific workers. ... Edinburghs location in Scotland Edinburgh viewed from Arthurs Seat. ... Louis-Philippe of France (October 6, 1773–August 26, 1850), served as the Orleanist king of the French from 1830 to 1848. ... Napoleon François Joseph Charles Bonaparte (March 20, 1811 -July 22, 1832), Duke of Reichstadt, was briefly the second Emperor of the French. ...

Arago's fame as an experimenter and discoverer rests mainly on his contributions to magnetism and still more to optics. He showed that a magnetic needle, made to oscillate over nonruginous surfaces, such as water, glass, copper, etc., falls more rapidly in the extent of its oscillations according as it is more or less approached to the surface. This discovery, which earned him the Copley Medal of the Royal Society in 1825, was followed by another, that a rotating plate of copper tends to communicate its motion to a magnetic needle suspended over it ("magnetism of rotation"). Arago is also fairly entitled to be regarded as having proved the long-suspected connexion between the aurora borealis and the variations of the magnetic pa ments[?]. In optics we owe to him not only important optical discoveries of his own, but the credit of stimulating the genius of Jean-Augustin Fresnel, with whose history, as well as with that of Etienne-Louis Malus and of Thomas Young, this part of his life is closely interwoven. Shortly after the beginning of the 19th century the labours of at least three philosophers were shaping the doctrine of the undulatory, or wave, theory of light. Fresnel's arguments in favour of that theory found little favour with Laplace, Poisson and Biot, the champions of the emission theory; but they were ardently espoused by Humboldt and by Arago, who had been appointed by the Academy to report on the paper. This was the foundation of an intimate friendship between Arago and Fresnel, and of a determination to carry on together further fundamental laws of the polarization of light known by their means. As a result of this work Arago constructed a polariscope, which he used for some interesting observations on the polarization of the light of the sky. To him also due the discovery of the power of rotatory polarization exhibited by quartz, and last of all, among his many contributions to the support of the undulatory hypothesis, comes the experimentum crucis which he proposed to carry out for measuring directly the velocity of light in air and in water glass. On the emission theory the velocity should be accelerated by an increase of density in the medium; on the wave theory, it should be retarded. In 1838 he communicated to the Academy the details of his apparatus, which utilized the relaying mirrors employed by Charles Wheatstone in 1835 for measuring the velocity of the electric discharge; but owing to the great care required in the carrying out of the project, and to the interruption to his labours caused by the revolution of 1848, it was the spring of 1850 before he was ready to put his idea the test; and then his eyesight suddenly gave way. Before his death, however, the retardation of light in denser media was demonstrated by the experiments of H. L. Fizeau and B. L. Foucault, which, with improvements in detail, were based on the plan proposed by him. The Copley Medal is a scientific award for work in any field of science, the highest award granted by the Royal Society of London. ... The Royal Society of London is claimed to be the oldest learned society still in existence. ... Aurora borealis Polar aurorae are optical phenomena characterized by colorful displays of light in the night sky. ... Augustin Fresnel Augustin-Jean Fresnel (pronounced fray-NELL) (May 10, 1788 – July 14, 1827), was a French physicist who contributed significantly to the establishment of the wave theory of light and optics. ... Etienne-Louis Malus (July 23, 1775 - February 24, 1812) was a French officer, engineer, physicist, and mathematician. ... Thomas Young, English scientist Thomas Young (June 13, 1773 – May 10, 1829) was an English scientist and researcher. ... This article treats polarization in electrodynamics. ... Quartz is the second most abundant mineral in the Earths crust. ... Sir Charles Wheatstone (February 6, 1802 _ October 19, 1875) was the British inventor of many innovations including the English concertina an early form of microphone the Playfair cipher (named for Lord Playfair, the person who publicized it) and the Wheatstone bridge. ...

He remained a consistent republican to the end, and after the coup d'état of 1852, though suffering first from diabetes, then from from Bright's disease, complicated by dropsy, he resigned his post as astronomer rather than take the oath of allegiance. Napoleon III gave directions that the old man should be in no way disturbed, and should be left free to say and do what he liked. In the summer of 1853 Arago was advised by his physicians to try the effect of his native air, and he accordingly set out to the eastern Pyrenees, but it was ineffective and he died in Paris. A coup détat (pronounced kū dā ta), or simply a coup, is the sudden overthrow of a government, usually done by a small group that just replaces the top power figures. ... 1852 was a leap year starting on Thursday (see link for calendar). ... This article is about the disease that features high blood sugar. ... Brights Disease is a historical classification of kidney diseases that would be described in modern medicine as acute or chronic nephritis. ... Charles Louis Napoléon Bonaparte (April 20, 1808, Paris - January 9, 1873, Chislehurst, Kent, England) was a President of France, and later, Emperor of the French. ...

Arago's works were published after his death under the direction J. A. Barral, in 17 vols., 8vo, 1854-1862; also separately his Astronomie populaire, in 4 vols.; Notices biographiques, in 3 vols.; Indices scientifiques, in 5 vols.; Voyages scientifiques, in 1 vol.; Grimoires scientifiques, in 2 vols.; Mélanges, in I vol.; and Tables analytiques et documents importants (with portrait), in 1 vol. English translations of the following portions of his works have appeared : Treatise on Comets, by C. Gold, C.B. (London, 1833); also translated Smyth and Grant (London, 1861); Euloge of James Watt, by Muirhead (London, 1839); also translated, with notes, by Brougham; Popular Lectures on Astronomy, by Walter Kelly d Rev. L. Tomlinson (London, 1854); also translated by Dr W. H. Smyth and Prof. R. Grant, 2 vols. (London, 1855); Arago's Autography, translated by the Rev. Baden Powell (London, 1855, 58); Arago's Meteorological Essays, with introduction by Humboldt, translated under the superintendence of Colonel Sabine ondon, 1855), and Arago's Biographies of Scientific Men, translated by Smyth, Powell and Grant, 8vo (London, 1857).

Craters on Mars and the Moon, and a ring of Neptune, are named after him. This article is about impact craters, also known as meteor craters. ... Mars is the fourth planet from the Sun in the solar system, named after the Roman god of war (the counterpart of the Greek Ares), on account of its blood red color as viewed in the night sky. ... Crust composition Oxygen 43% Silicon 21% Aluminium 10% Calcium 9% Iron 9% Magnesium 5% Titanium 2% Nickel 0. ... A planetary ring is a ring of dust and other small particles orbiting around a planet in a flat disc-shaped region. ... Atmospheric characteristics Atmospheric pressure 100-300 kPa Hydrogen >84% Helium >12% Methane 2% Ammonia 0. ...

External links

• Biography (http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Arago.html) at the MacTutor archive

The MacTutor history of mathematics archive is a website hosted by University of St Andrews in Scotland. ...

Obituaries

• MNRAS 14 (1854) 102 (http://adsabs.harvard.edu//full/seri/MNRAS/0014//0000102.000.html)