On This Day in Math - December 25

   

God Bless Us, Everyone

Me, and Tiny Tim

The 359th day of the year; 359 is a Sophie Germain prime. If you start with n=89 and iterate 2n+1 you will get a string of primes that includes 359. (How many in all?)

It is also the smallest Sophie Germain prime whose reversal, 953 is also a Sophie Germain prime and sadly, the last day of the year that is prime.  (On most years this year day occurs on Christmas Day, a fitting day for the last prime day of the year .)

There are only 88 year days which are not the sum of three non-zero squares.  359 is the last one. 

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EVENTS
1843 Sir Henry Cole British industrial designer, museum director and writer who produced the first commercial Christmas card. In 1843, wishing to save much handwriting of seasonal correspondence, Cole introduced the world's first commercial Christmas card. He commissioned artist John Callcott Horsley to make the artwork for 1000 hand-coloured lithographs. (Individuals' homemade Christmas cards had existed earlier.) (See Image at top)

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1640 Fermat's theorem on sums of two squares states that an odd prime p can be expressed as:

p= x² + y² with x and y integers, if and only if p≡1mod4$p\equiv 1mod4$

The prime numbers for which this is true are called Pythagorean primes. For example, the primes 5, 13, 17, 29, 37 and 41 are all congruent to 1 modulo 4,

Albert Girard was the first to make the observation, describing all positive integral numbers (not necessarily primes) expressible as the sum of two squares of positive integers; this was published in 1625.The statement that every prime p of the form 4n+1 is the sum of two squares is sometimes called Girard's theorem. For his part, Fermat wrote an elaborate version of the statement (in which he also gave the number of possible expressions of the powers of p as a sum of two squares) in a letter to Marin Mersenne dated December 25, 1640: for this reason this version of the theorem is sometimes called Fermat's Christmas theorem. *Wik

Statue of Pierre de Fermat by Alexandre Falguière in Beaumont-de-Lomagne, Tarn-et-Garonne France.

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1656 Huygens (who was a bachelor) spent Christmas Day making the first model of a pendulum clock. *VFR(And then he was visited by three spirits.... oops, wrong story)

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In 1741, the Centigrade temperature scale was devised by astronomer Anders Celsius (1701-44) and incorporated into a Delisle thermometer at Uppsala in Sweden. Celsius divided the fixed-point range of the Fahrenheit scale (the freezing and boiling temperatures of water) into 100 equal divisions, but curiously set the freezing point at 100 and the boiling point at 0. This reverse scaling was changed to match the sense of the other temperature scales after Celsius's death.*TIS

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1758 Halley’s comet first sighted after he predicted its return. After Newton explained planetary motion, he suggested that comets could have elongated elliptical orbits. Halley’s comet has eccentricity 0.9675. [UMAP Journal, 4(1983), p. 162] *VFR
In 1758, the predicted return of Halley's comet was first sighted by German farmer and amateur astronomer, Johann Georg Palitzsch, as a faint object in Pisces. Edmund Halley had predicted in 1705 the return of the comet to the Earth's vicinity every 75.5 years. For the first time the scientific prediction had been proven. Halley himself had died 16 years before this new event. Palitzsch also observed the 6 Jun 1761 transit of Venus, when he saw a black band linking Venus and the Sun near the beginning and end of the transit ("black drop effect") and correctly interpreted this as evidence that Venus possessed an atmosphere. He also measured the period of the variation of the brightness of the star Algol. *TIS
The BAYEUX TAPESTRY (Tapisserie de la Reine Mathilde) includes a clear picture of Halley's Comet, as shown on the stamp below.

and here is a Blog regarding the return in 1758.

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In 1780, Luigi Galvani recorded, "The electric fluid should be considered a means to the nervo-muscular force." He reached this conclusion from work in his laboratory in Bologna, Italy, after a series of experiments and his accidental discovery that muscles are operated by electrical stimulation of nerves. He worked diligently along these lines, but waited for eleven years before he published the results and an ingenious and simple theory. His theory was that of a nervous electric fluid, secreted by the brain, conducted by the nerves, and stored in the muscles. Though his ideas were abandoned by scientists on account of later discoveries, his work opened the way to new research in the physiology of muscle and nerve and pioneered the subject of electrophysiology. *TIS

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1884 On the first Christmas after it was printed, the future classic, Flatland, was reviewed in the Times UK, which gave it a less than sterling review.

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In 1999, space shuttle Discovery's astronauts finished their maintenance work on the Hubble Space Telescope, installing correcting optics to repair problems due to a design flaw in the mirror. The first images the Hubble Telescope took after its original launch were disappointingly fuzzy, but after this repair mission the instrument returned crisp images of a clarity never before possible from terrestrial observatories *TIS

This image of NGC 6544 combines data from two of Hubble's instruments — the Advanced Camera for Surveys and Wide Field Camera 3 — as well as two separate astronomical observations.

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BIRTHS
1642 Isaac Newton born on Julian Calendar. (5 January 1643 New style) *VFR
Born 25 Dec 1642; died 20 Mar 1727. English physicist and mathematician, who made seminal discoveries in several areas of science, and was the leading scientist of his era. His study of optics included using a prism to show white light could be split into a spectrum of colours. The statement of his three laws of motion are fundamental in the study of mechanics. He was the first to describe the moon as falling (in a circle around the earth) under the same influence of gravity as a falling apple, embodied in his law of universal gravitation. As a mathematician, he devised infinitesimal calculus to make the calculations needed in his studies, which he published in Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy, 1687)*TIS

Newton Statue in Trinity College Chapel, Cambridge, UK

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1724  John Michell ( 25 December 1724 – 21 April 1793) was an English natural philosopher and clergyman who provided pioneering insights into a wide range of scientific fields including astronomy, geology, optics, and gravitation. Considered "one of the greatest unsung scientists of all time", he is the first person known to have proposed the existence of black holes, and the first to have suggested that earthquakes travelled in (seismic) waves. Recognizing that double stars were a product of mutual gravitation, he was the first to apply statistics to the study of the cosmos. He invented an apparatus to measure the mass of the Earth, and explained how to manufacture an artificial magnet. He has been called the father both of seismology and of magnetometry.

According to one science journalist, "a few specifics of Michell's work really do sound like they are ripped from the pages of a twentieth century astronomy textbook." The American Physical Society (APS) described Michell as being "so far ahead of his scientific contemporaries that his ideas languished in obscurity, until they were re-invented more than a century later". The Society stated that while "he was one of the most brilliant and original scientists of his time, Michell remains virtually unknown today, in part because he did little to develop and promote his own path-breaking ideas"  *Wik

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1763 Claude Chappe (25 Dec 1763; 23 Jan 1805) French engineer who invented the semaphore visual telegraph. He began experimenting in 1790, trying various types of telegraph. An early trial used telescopes, synchronized pendulum clocks and a large white board, painted black on the back, with which he succeeded in sending a message a few sentences long across a 16km (10mi) distance. To simplify construction, yet still easily visible to read from far away, he changed to using his semaphore telegraph in 1793. Smaller indicators were pivoted at each end of large horizontal member. The two indicators could each be rotated to stand in any of eight equally spaced positions. By setting them at different orientations, a set of corresponding codes was used to send a message.*TIS

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1884  Sotero Prieto Rodríguez (December 25, 1884 – May 22, 1935) was a Mexican mathematician who taught at the National Autonomous University of Mexico. Among his students were physicist Manuel Sandoval Vallarta, physicist and mathematician Carlos Graef Fernández, and engineer and Rector of UNAM Nabor Carrillo Flores.

Still being very young, he began teaching and carried out mathematical studies. He influenced notably the change and progress of mathematical research in Mexico, by influencing the then new generation of engineers and students of the exact sciences at the National Autonomous University of Mexico.

He was a teacher of Manuel Sandoval Vallarta in the Escuela Nacional Preparatoria and of Alberto Barajas Celis, Carlos Graef Fernández and of Nabor Carrillo Flores in the Escuela Nacional de Ingenieros, currently the Facultad de Ingeniería.

In 1932, he established the Mathematics Section of the Sociedad Científica "Antonio Alzate", currently the Academia Nacional de Ciencias de México, where his students presented the results of their research.

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1900 Antoni Szczepan Zygmund (25 Dec 1900 in Warsaw, Russian Empire (now Poland)
- 30 May 1992 in Chicago, Illinois, USA) Zygmund's work in harmonic analysis has application in the theory of waves and vibrations. He also did major work in Fourier analysis and its application to partial differential equations.*SAU

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1905 Gottfried Maria Hugo Köthe (born 25 December 1905 in Graz; died 30 April 1989 in Frankfurt) was an Austrian mathematician working in abstract algebra and functional analysis.*SAU Köthe's best known work has been in the theory of topological vector spaces. In 1960, volume 1 of his seminal monograph Topologische lineare Räume was published (the second edition was translated into English in 1969). It was not until 1979 that volume 2 appeared, this time written in English. He also made contributions to the theory of lattices. *Wik

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DEATHS
1921 Piers Bohl (October 23, 1865 – December 25, 1921) was a Latvian mathematician, who worked in differential equations, topology and quasi-periodic functions.
He was born in 1865 in Walk, Livonia, in the family of a poor Baltic German merchant. In 1884, after graduating from a German school in Viljandi, he entered the faculty of physics and mathematics at the University of Tartu. In 1893 Bohl was awarded his Master's degree. This was for an investigation of quasi-periodic functions. The notion of quasi-periodic functions was generalised still further by Harald Bohr when he introduced almost-periodic functions. *Wik

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1929 Percy Alexander MacMahon (b. 26 September 1854, Sliema, Malta – 25 December 1929, Bognor Regis, England) was a mathematician, especially noted in connection with the partitions of numbers and enumerative combinatorics. MacMahon was elected a Fellow of the Royal Society in 1890. He received the Royal Society Royal Medal in 1900, the Sylvester Medal in 1919, and the Morgan Medal by the London Mathematical Society in 1923. MacMahon was the President of the London Mathematical Society from 1894 to 1896.
MacMahon is best known for his study of symmetric functions and enumeration of plane partitions; see MacMahon Master theorem. His two volume Combinatory analysis, published in 1915/16, is the first major book in enumerative combinatorics. MacMahon also did pioneering work in recreational mathematics and patented several successful puzzles.*WIK

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1930 Eugen Goldstein (5 Sep 1850, 25 Dec 1930) German physicist who discovered and named canal rays (1886) which emerge through holes in the anodes of low-pressure electrical discharge tubes (later shown to be positively charged particles). Earlier, he coined the term "cathode ray" (1876) emitted from a cathode. He was the first to see that they could cast a shadow, and were emitted at right angles to the surface. He also investigated the wavelengths of light emitted by metals and oxides when canal rays impinge on them. When the Berlin Urania, opened in 1889 it had five scientific departments and a "science theatre", it was Goldstein who had recommended the "hall of physics in which the visitor could experiment on his own". Students of his that continued his work included Wien and Stark. *TIS

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1941 Theodor Molien​ or Fedor Eduardovich Molin​ (September 10, 1861 - December 25, 1941) was a Baltic-German mathematician. He was born in Riga, Latvia, which at that time was a part of Russian Empire. Molien studied associative algebras and polynomial invariants of finite groups.*Wik

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1944 Wilhelm Kutta was a German engineer who is best known for his work on the numerical solution of differential equations (the Runge-Kutta method).*SAU Kutta was born in Pitschen, Upper Silesia (today Byczyna, Poland). He attended the University of Breslau from 1885 to 1890, and continued his studies in Munich until 1894, where he became the assistant of Walther Franz Anton von Dyck. From 1898, he spent half a year at the University of Cambridge.[1] From 1899 to 1909 he worked again as an assistant of von Dyck in Munich; from 1909 to 1910 he was adjunct professor at the Friedrich Schiller University Jena. He was professor at the RWTH Aachen from 1910 to 1912. Kutta became professor at the University of Stuttgart in 1912, where he stayed until his retirement in 1935.
In 1901, he co-developed the Runge-Kutta method, used to solve ordinary differential equations numerically. He is also remembered for the Zhukovsky-Kutta aerofoil, the Kutta-Zhukovsky theorem and the Kutta condition in aerodynamics. Kutta died in Fürstenfeldbruck, Germany in 1944. *Wik

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2000 Willard Van Orman Quine (June 25, 1908 – December 25, 2000) (known to intimates as "Van")  was an American philosopher and logician in the analytic tradition. From 1930 until his death 70 years later, Quine was continuously affiliated with Harvard University in one way or another, first as a student, then as a professor of philosophy and a teacher of mathematics, and finally as a professor emeritus who published or revised several books in retirement. He filled the Edgar Pierce Chair of Philosophy at Harvard from 1956 to 1978. A recent poll conducted among philosophers named Quine one of the five most important philosophers of the past two centuries. He won the first Schock Prize in Logic and Philosophy in 1993, for "his systematical and penetrating discussions of how learning of language and communication are based on socially available evidence and of the consequences of this for theories on knowledge and linguistic meaning.*Wik

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2010 Gavin Brown AO FAA CorrFRSE (27 February 1942 – 25 December 2010) was a Scottish-born mathematician and long-serving Vice-Chancellor and Principal of the University of Sydney between 1996 and 2008.

After attending secondary school at Madras College in St Andrews, Brown graduated with a Master of Arts degree (1st Class Honours and the Duncan Medal) from the University of St Andrews (1963), and a Doctor of Philosophy degree from the University of Newcastle upon Tyne (1966). His academic career began at the University of Liverpool, where he became a senior lecturer in mathematics.

Brown accepted the Chair of Pure Mathematics at the University of New South Wales in 1975 and he and his family emigrated to Australia. At the University of New South Wales, Brown held a number of academic administrative posts, including Head of the Department of Pure Mathematics, Head of the School of Mathematics, and Dean of the Faculty of Science. During this time, he was awarded the Sir Edmund Whittaker Memorial Prize and the Australian Mathematical Society Medal.

In 1992, Brown became the Deputy Vice-Chancellor (Research) at the University of Adelaide. Later, in 1994, he became the Vice-Chancellor. He took up the position of Vice-Chancellor and Principal of the University of Sydney in 1996 and retired from the post in 2008.

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2016  Vera Florence Cooper Rubin (July 23, 1928 – December 25, 2016) was an American astronomer who pioneered work on galaxy rotation rates. She uncovered the discrepancy between the predicted and observed angular motion of galaxies by studying galactic rotation curves. By identifying the galaxy rotation problem, her work provided evidence for the existence of dark matter. These results were later confirmed over subsequent decades. *Wik

Throughout her schooling, Rubin faced the banal sexism all too common at the time for women interested in science. Her high school physics teacher ignored the few girls in class; a college admissions interviewer encouraged her to consider painting astronomical objects rather than studying them. Rubin was not deterred. “She took it all with courage, and with persistence,” says Bahcall, who was a longtime friend and colleague of Rubin.

Rubin studied astronomy at Vassar College, married mathematical physicist Bob Rubin, and began graduate school at Cornell in 1948. She completed her master’s thesis on the rotation of the universe, kicking off a long career investigating hidden galactic behavior, and a professor suggested Rubin present this research at a meeting of the American Astronomical Society (AAS) in 1950. There, she encountered a chilly reception. “I gave my memorized 10-minute talk, acceptably I thought. Then one by one many angry sounding men got up to tell me why I could not do ‘that,’” she wrote.

In 2019, almost 70 years after Rubin faced that hostile crowd at the 1950 AAS meeting, (and almost three years after her Death) the Society convened in Honolulu to agree on renaming the Large Synoptic Survey Telescope as the Vera C. Rubin Observatory. After its construction is complete, the Rubin Observatory will be the site of a 10-year survey of a mammoth swath of night sky. Bahcall sees this honor as the perfect tribute to Rubin, who cherished the many long nights she spent in observatories, peering through telescopes. “She loved being in the dome.” *APS Org

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2018 Nancy Grace Roman (May 16, 1925..Nashville, Tennessee, U.S.-December 25, 2018 (aged 93)) was an American astronomer and one of the first female executives at NASA. She is known to many as the "Mother of Hubble" for her role in planning the Hubble Space Telescope. Throughout her career, Roman was also an active public speaker and educator, and an advocate for women in the sciences.
When Roman was eleven years old, she showed interest in astronomy by forming an astronomy club among her classmates in Nevada. She and her classmates got together once a week and learned about constellations from books. Although discouraged by those around her, Roman knew by the time she was in high school that she wanted to pursue her passion for astronomy. She attended Western High School in Baltimore where she participated in an accelerated program and was graduated in three years. *Wik

Nancy Grace Roman uses the telescope at Yerkes Observatory in Williams Bay, WI in 1948. Famous astronomers Edwin Hubble and Subrahmanyan Chandrasekhar also studied at Yerkes.

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Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell

On This Day in Math - December 24

 

The travelers looked up to see an omen shining in the sky,
Earthrise: See 1968 below

The 358th day of the year; 358 is twice a prime, and the sum of six consecutive primes, 47 + 53 + 59 + 61 + 67 + 71
The sum of the first 358 prime numbers is itself a prime number.

and in case you were curious, the 358th digit of pi (after the decimal point) is 3.

 The product of the first 358 integers is not divisible by the sum of the first 358 integers.  That means that for any numbers x, y both greater than 1, there is no solution to the equation x + xy + y =158.  If this is not a leap year, then this is the last year day this year with this quality.  (younger students might try to show these interrelated ideas with a smaller number like 10.)

35+ 8 + 3 + 58 + 3 + 5 + 8 = 3 x 5 x 8 = 120

Derek Orr pointed out that 358 = 2 x 179, and 2+ 179 = 181 is prime, and 2 + 1 + 7 + 9 = 19 is also prime.  

358 = 18^2 + 5^2 + 3^2 = 14^2 + 9^2 + 9^2

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EVENTS
1734 A letter and drawing by Martha Gerrish, a woman of New England, described a Parhelion, (aka Sundog, an atmospheric optical phenomenon that consists of a bright spot to one or both sides of the Sun) a rare astronomical phenomenon. Gerrish comments ‘if this came from a masculine hand, I believe it would be an acceptable present to the Royal Society’. This is the first letter to the Royal Society known to be sent by a woman in her own name and demonstrates that women contributed to science even when their work was not made public.  

The photograph shows very bright sun dogs in Fargo, North Dakota.*Wij

*Royal Society Org

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1754 Euler writes to Muller in St Petersburg and describes d'Alembert as "the most argumentative man in the world," and calls him, "hated by everyone in Paris." *Thomas L. Hankins, Jean d'Alembert: science and the Enlightenment; pg 58

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1819 Bernard Bolzano was dismissed from his theological chair at the University of Prague and put under police supervision for his unorthodox religious views. In mathematics he helped remove the scandal of infinitesimals from the calculus. *SAU

To the foundations of mathematical analysis he contributed the introduction of a fully rigorous ε–δ definition of a mathematical limit. Bolzano was the first to recognize the greatest lower bound property of the real numbers. Like several others of his day, he was skeptical[dubious – discuss] of the possibility of Gottfried Leibniz's infinitesimals, that had been the earliest putative foundation for differential calculus. Bolzano's notion of a limit was similar to the modern one: that a limit, rather than being a relation among infinitesimals, must instead be cast in terms of how the dependent variable approaches a definite quantity as the independent variable approaches some other definite quantity.

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1849 Gauss writes to the Astronomer Johann Franz Encke in response to Encke's remarks about the Frequency of Primes.

"Most Honored Friend!
. . .The kind communication of your remarks on the frequency of prime numbers
was interesting to me in more than one respect. You have reminded me of
my own pursuit of the same subject, whose first beginnings occurred a very long
time ago, in 1792 or 1793, when I had procured for myself Lambert’s supplement
to the table of logarithms. Before I had occupied myself with the finer
investigations of higher arithmetic, one of my first projects was to direct my
attention to the decreasing frequency of prime numbers, to which end I counted
them up in several chiliads (sets of a thousand) and recorded the results on one of the affixed white sheets. I soon recognized, that under all variations of this frequency, on average, it is nearly inversely proportional to the logarithm..."

Gauss never published his results. The first published version of the Prime Number Theorem was by Legendre in 1798. *John Derbyshire, Prime Obsession

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1899 the Physico-Mathematic Society of Kazan (Russia) celebrated a Jubilee in honor of the twenty-fifth year of professional and scientific service of its President, Professor A. Vasiliev. It is also the fifteenth year of his presidency. Professor Vasiliev has been an extraordinarily important figure in Russian science. Outside of Russia he has chiefly been known for his remarkable discourse on Lobachevski. *The American Mathematical Monthly, Vol. 7, No. 1 (Jan., 1900), p. 30

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1906 First Long Range transmission of voice: Reginald Aubrey Fessenden was a Canadian inventor and engineer with 300 patents. He broadcast the first program of voice and music. In 1893, Fessenden moved to Pittsburgh as the head of electrical engineering at the university, Fessenden read of Marconi's work and began experimenting himself. Marconi could only transmit Morse code. But Fessenden's goal was to transmit the human voice and music. He invented the "continuous wave": sound superimposed onto a radio wave for transmission. A radio receiver extracts the signal so the listener with the original sound. Fessenden made the first long-range transmissions of voice on Christmas Eve 1906 from a station at Brant Rock, Massachusetts, heard hundreds of miles out in the Atlantic.*TIS He used a 42 kHz radio frequency Alexanderson alternator which produced about 1kW of power. Although Fessenden's work made voice radio possible, it would take 10 years and the First World War before it became commonplace. Throughout this period, radio was still seen primarily as point-to-point communication between transmitting stations--a sort of wireless telephone. *CHM

Although Fessenden ceased radio research after his dismissal from NESCO in 1911, he continued to work in other fields. As early as 1904 he had helped engineer the Niagara Falls power plant for the newly formed Hydro-Electric Power Commission of Ontario. However, his most extensive work was in marine communication as consulting engineer with the Submarine Signal Company which built a widely used aid to navigation using bells, termed a submarine signal, acting much as an underwater foghorn. While there, he invented the Fessenden oscillator, an electromechanical transducer. Though the company immediately began replacing bells and primitive receivers on ships with the new device, it was also the basis for entirely new applications: underwater telegraphy and sonic distance measurement. The later was the basis for sonar (SOund NAvigation Ranging), echo-sounding and the principle applied to radar (RAdio Detection And Ranging). The device was soon put to use for submarines to signal each other, as well as a method for locating icebergs, to help avoid another disaster like the one that sank Titanic. While the company quickly applied his invention to replace the bells of its systems and entered acoustic telegraphy it ignored the echo ranging potential. The echo sounding was invented in 1912 by German physicist Alexander Behm *Wik 

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1912 Irving Fisher (1867-1947), a Yale professor, patented an archiving system with index cards. On 1 Jul 1925, Fisher's own firm, the Index Visible Company, merged with its principal competitor to form Kardex Rand Co., later Remington Rand, still later Sperry Rand. Fisher earned about $1million$\$1million$ for the invention, which grew to the princely sum of $9million$\$9million$ before being lost in the stock market crash of 1929. Fisher is widely regarded as the greatest economist America has produced, who made much use of mathematics in his work.*TIS

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1968 On Christmas Eve, the Apollo 8 astronauts saw the entirety of Earth for the first time. Turing their cameras to the Earth they took the first three pictures of the whole earth from space. The one above, by William Anders, has been called "the most influential environmental photograph ever taken." *Wik, NASA

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2002  Sun Microsystems wins a major antitrust victory against Microsoft when a federal judge ordered Microsoft to distribute Sun's Java programming language in its Microsoft Windows operating system. Another provision of the decision required that Microsoft cease the shipment of a version of Java that Sun contended was outdated and could discourage programmers from using it for software development. The court case was one of many that Microsoft had contended with in the face of anti-trust allegations by both corporate competitors and federal and state government agencies.

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In 2004, the Huygens probe began a 22-day descent towards Saturn's largest moon, Titan. It had been launched as part of the Cassini spacecraft in 1997, and together they entered Saturn's orbit in June 2004. As the paths of the spacecraft and Titan converged, Cassini ejected the Huygens probe, sending it on a 22-day coast toward the cloud-covered moon. It landed 14 Jan 2005, and sent back photographs of the moon's surface. Cassini will remain in orbit around Saturn until at least July 2008. The Cassini-Huygens mission to study Saturn and its 33 known moons resulted from an unprecedented cooperative effort between the NASA of the United States, the European Space Agency and Italy's space program, at a cost of $3.3 billion. *TIS

An artist's concept of the Huygens probe sitting on Titan.

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BIRTHS
1740 Anders Johan Lexell (December 24, 1740 – December 11, 1784 (Julian calendar: November 30)) was a Swedish-born Russian astronomer, mathematician, and physicist who spent most of his life in Russia where he is known as Andrei Ivanovich Leksel.
Lexell made important discoveries in polygonometry and celestial mechanics; the latter led to a comet named in his honor. La Grande Encyclopédie states that he was the prominent mathematician of his time who contributed to the spherical trigonometry with new and interesting solutions, which he took as a basis for his research of comet and planet motion. His name was given to one of the theorems about spherical triangles.
Lexell was one of the most prolific members of the Russian Academy of Sciences at that time, having published 66 papers in 16 years of his work there. A statement attributed to Leonhard Euler expresses high approval of Lexell's works: "Besides Lexell, such a paper could only be written by D'Alambert or me". Daniel Bernoulli also praised his work, writing in a letter to Johann Euler "I like Lexell's works, they are profound and interesting, and the value of them is increased even more because of his modesty, which adorns great men".
Lexell did not have a family and kept up a close friendship with Leonhard Euler and his family. He witnessed Euler's death at his house and succeeded him to the chair of the mathematics department at the Russian Academy of Sciences, but died the following year. The asteroid 2004 Lexell is named in his honour, as is the lunar crater Lexell.*Wik

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1818 James Prescott Joule (24 Dec 1818; 11 Oct 1889) English physicist who established that the various forms of energy - mechanical, electrical, and heat - are basically the same and can be changed, one into another. Thus he formed the basis of the law of conservation of energy, the first law of thermodynamics. He discovered (1840) the relationship between electric current, resistance, and the amount of heat produced. In 1849 he devised the kinetic theory of gases, and a year later announced the mechanical equivalent of heat. Later, with William Thomson (Lord Kelvin), he discovered the Joule-Thomson effect. The SI unit of energy or work , the joule (symbol J), is named after him. It is defined as the work done when a force of 1 newton moves a distance of 1 metre in the direction of the force.*TIS

Joule's apparatus for measuring the mechanical equivalent of heat

*Wik

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1822 Charles Hermite (24 Dec 1822; 14 Jan 1901) French mathematician whose work in the theory of functions includes the application of elliptic functions to provide the first solution to the general equation of the fifth degree, the quintic equation. In 1873 he published the first proof that e is a transcendental number. Hermite is known also for a number of mathematical entities that bear his name, Hermite polynomials, Hermite's differential equation, Hermite's formula of interpolation and Hermitian matrices. Poincaré is the best known of Hermite's students.*TIS

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1838 Thorvald Nicolai Thiele (24 December 1838 – 26 September 1910) was a Danish astronomer, actuary and mathematician, most notable for his work in statistics, interpolation and the three-body problem. He was the first to propose a mathematical theory of Brownian motion. Thiele introduced the cumulants and (in Danish) the likelihood function; these contributions were not credited to Thiele by Ronald A. Fisher, who nevertheless named Thiele to his (short) list of the greatest statisticians of all time on the strength of Thiele's other contributions.
Thiele also was a founder and Mathematical Director of the Hafnia Insurance Company and led the founding of the Danish Society of Actuaries. It was through his insurance work that he came into contact with fellow mathematician Jørgen Pedersen Gram. Asteroid 843 Nicolaia is named in his honor. *Wik

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1868 Emanuel Lasker (24 Dec 1868 in Berlinchen, Prussia (now Barlinek, Poland) - 11 Jan 1941 in New York, USA) Lasker became World Chess Champion in 1894 and held the championship until 1921. In mathematics he introduced the notion of a primary ideal. *SAU

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1904 Sir William Hunter McCrea FRS (13 December 1904, Dublin – 25 April 1999) was an English astronomer and mathematician. He went to Trinity College, Cambridge in 1923 where he studied Mathematics, later gaining a PhD in 1929 under Ralph H. Fowler. He was later appointed a lecturer of Mathematics at the University of Edinburgh in 1929. He also served as reader and assistant professor at Imperial College London. In 1936 he became head of the mathematics department at the Queen's University of Belfast. After serving in the war, he joined the mathematics department at Royal Holloway College in 1944 (the McCrea Building on Royal Holloway's campus is named after him). In 1965, McCrea created the astronomy centre of the physics department at the University of Sussex.
In 1928, he studied Albrecht Unsöld's hypothesis, and discovered that three quarters of the Sun is made of Hydrogen, and about one quarter is Helium, with 1% being other elements. Previous to this many people thought the Sun consisted mostly of Iron. After this, people realized most stars consist of Hydrogen.
McCrea was president of the Royal Astronomical Society from 1961-3 and president of Section A of the British Association for the Advancement of Science from 1965-6. He was knighted in 1985. He won the Gold Medal of the Royal Astronomical Society in 1976. McCrea died on April 25, 1999 in Lewes. *Wik

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1910 William Hayward Pickering (24 Dec 1910; 15 Mar 2004) Engineer and physicist, head of the team that developed Explorer 1, the first U.S. satellite. He collaborated with Neher and Robert Millikan on cosmic ray experiments in the 1930s, taught electronics in the 1930s, and was at Caltech during the war. He spent the rest of his career with the Jet Propusion Laboratory, becoming its Director (1954) with responsibility for the U.S. unmanned exploration of the planets and the solar system. Among these were the Mariner spacecraft to Venus and Mercury, and the Viking mission to Mars. The Voyager spacecraft yielded stunning photographs of the planets Jupiter and Saturn.*TIS

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1916  Charles Frederick Mosteller (December 24, 1916 – July 23, 2006) was an American mathematician, considered one of the most eminent statisticians of the 20th century. He was the founding chairman of Harvard's statistics department from 1957 to 1971, and served as the president of several professional bodies including the Psychometric Society, the American Statistical Association, the Institute of Mathematical Statistics, the American Association for the Advancement of Science, and the International Statistical Institute.

Mosteller worked in Samuel Wilks's Statistical Research Group in New York city during World War II on statistical questions about airborne bombing. He received his PhD in mathematics from Princeton University in 1946.

He was hired by Harvard University's Department of Social Relations in 1946, where he received tenure in 1951 and served as acting chair from 1953 to 1954. He founded the Department of Statistics and served as its first chairman from 1957 to 1969, 1973, 1975 to 1977. He chaired the Department of Biostatistics at the Harvard School of Public Health from 1977 to 1981 and later the Department of Health Policy and Management in the 1980s. His four chairmanships have not been matched. He also taught courses at Harvard Law School and Harvard's Kennedy School of Government.

He worked with his mathematical assistant Cleo Youtz from the 1950s until his departure from Harvard in 2003, and had an administrative assistant. He was well known for being a good writer, insisting on doing up to fifteen drafts of a paper or book chapter before showing it to his colleagues and several additional drafts before submitting the paper to a journal.

Mosteller was an elected member of the American Academy of Arts and Sciences (1954), the American Philosophical Society (1961), and the United States National Academy of Sciences (1974)] He retired from classroom teaching in 1987, but continued working and publishing at Harvard through 2003. On January 3, 2004, he moved to Arlington, Virginia, to be closer to his children. *Wik

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DEATHS

(How sad to be one of these people who died on Christmas Eve)
1872 William John Macquorn Rankine (5 Jul 1820, 24 Dec 1872) Scottish engineer and physicist and one of the founders of the science of thermodynamics, particularly in reference to steam-engine theory. As the chair (1855) of civil engineering and mechanics at Glasgow, he developed methods to solve the force distribution in frame structures. Rankine also wrote on fatigue in the metal of railway axles, on Earth pressures in soil mechanics and the stability of walls. He was elected a Fellow of the Royal Society in 1853. Among his most important works are Manual of Applied Mechanics (1858), Manual of the Steam Engine and Other Prime Movers (1859) and On the Thermodynamic Theory of Waves of Finite Longitudinal Disturbance. *TIS (Many students are not aware there is a absolute temperature scale called the Rankine, named for him)

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1882 Johann Benedict Listing (25 July 1808 in Frankfurt am Main, Germany - 24 Dec 1882 in Göttingen, Germany)wrote one of the earliest texts on Topology. he studied the figure of the earth in minute detail; he made observations in meteorology, terrestrial magnetism, and spectroscopy; he wrote on the quantitative determination of sugar in the urine of diabetics; he promoted the nascent optical industry in Germany and better street lighting in Göttingen; he travelled to the world exhibitions in London 1851, Vienna 1873 and London 1876 as an observer for his government; he assisted in geodetic surveys; ... he invented a good many terms [other than topology], some of which have became current: "entropic phenomenon", "nodal points", "homocentric light", "telescopic system", " geoid" ...he coined "one micron" for the millionth of a metre ...*SAU

*Wik

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1927 William Henry Dines (5 Aug 1855, 24 Dec 1927) was an English meteorologist (like his father) and inventor of related measurement instruments such as the Dines pressure tube anemometer (the first instrument to measure both the velocity and direction of wind, 1901), a very lightweight meteorograph, and a radiometer (1920). He joined the Royal Meteorological Society study of the cause of the disastrous Tay Bridge collapse of 1879. His measurements of upper air conditions, first with kites and later by balloon ascents (1907), brought an understanding of cyclones from dynamic processes in the lower stratosphere rather than thermal effects nearer to the ground.*TIS

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1962 Wilhelm Friedrich Ackermann (29 March 1896 – 24 December 1962) was a German mathematician best known for the Ackermann function, an important example in the theory of computation.

In 1928, Ackermann helped David Hilbert turn his 1917 – 22 lectures on introductory mathematical logic into a text, Principles of Mathematical Logic. This text contained the first exposition ever of first-order logic, and posed the problem of its completeness and decidability (Entscheidungsproblem). Ackermann went on to construct consistency proofs for set theory (1937), full arithmetic (1940), type-free logic (1952), and a new axiomatization of set theory (1956).

In computability theory, the Ackermann function, named after Wilhelm Ackermann, is one of the simplest and earliest-discovered examples of a total computable function that is not primitive recursive. All primitive recursive functions are total and computable, but the Ackermann function illustrates that not all total computable functions are primitive recursive.

Later in life, Ackermann continued working as a high school teacher. He kept engaged in the field of research and published many contributions to the foundations of mathematics until the end of his life. He died in Lüdenscheid, West Germany in December 1962.

*Wik

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1994 Alfred Leon Foster (13 July 1904 in New York City, New York, USA - 24 Dec 1994 in Berkeley, California, USA) Foster went on to define the concept of a primal algebra generalising a Boolean algebra within the theory of varieties of universal algebras. In 1953 showed that the variety generated by a primal algebra has the same essential structure as the variety of Boolean algebras. He continued devoting his efforts to the structure theory of algebras that are generalizations of Boolean algebras and, more than ten years down the line in 1966, he published Families of algebras with unique (sub-)direct factorization. Equational characterization of factorization in Mathematische Annalen.*SAU

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2000 Laurence Chisholm Young (14 July 1905 – 24 December 2000) was a mathematician known for his contributions to measure theory, the calculus of variations, optimal control theory, and potential theory. He is the son of William Henry Young and Grace Chisholm Young, both prominent mathematicians.
The concept of Young measure is named after him. *Wik

*SAU

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Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell