On This Day in Math - July 26

  

Mathematics is the most exact science, and its conclusions are capable of absolute proof. But this is so only because mathematics does not attempt to draw absolute conclusions. All mathematical truths are relative, conditional
~Steinmetz, Charles P.

This is the 207th day of the year; 207 is the smallest possible sum of primes which are formed using each of the digits 1 through 9 (i.e., 89 + 61 + 43 + 7 + 5 + 2 = 207) *Prime Curios (So how many such sums can there be? And which of such sums are prime?)

There are exactly 207 different matchstick graphs with eight edges ( a matchstick graph is a graph that can be drawn in the plane in such a way that its edges are line segments with length one that do not cross each other) Here are a few of them:

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See more Math Facts for Every Year Day here

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EVENTS

1609 Thomas Harriot was the first person to make a drawing of the Moon through a telescope, on July 26, 1609, over four months before Galileo. Factoring to solve equations was once frequently called “Harriot’s Method.” *Wik

Thony Christie points out that, "Harriot’s drawings are very primitive, mere sketches, and cannot be compared with the justifiably famous moon drawings published by Galileo Galilei in his Sidereus Nuncius from 1610. Galileo unlike Harriot was a trained artist and realised that what he was seeing through his telescope were three dimensional landscape features, mountains, valleys, etc." Thony has a great blog about the naming of the features on the moon with more great images.

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1712 Brooke Taylor describes what we now call a “Taylor series” in a letter to John Machin on July 26, 1712. He would not publish about them until three years later. It would be another fifty years before the power of the method is realized by Lagrange, and another fifty before Cauchy gives a formal proof.

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1732 George Berkeley gave his farm near Newport, Rhode Island to the College of New Haven [now Yale University] to endow two graduate Fellows in Greek and Latin. This was the first provision for graduate study in America. Berkeley is known in mathematics for his Analyst (1734), which criticized the foundations of the calculus. See G. P. Conroy, “Berkeley and Education in America,” Journal for the History Ideas, 21(1960), pp. 211-221.

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1766 “To your care and recommendation am I indebted for having replaced a half-blind mathematician by a mathematician with both eyes, which will especially please the anatomical members of the academy.” So wrote Frederick the Great to d’Alembert, thanking him for his suggestion of hiring Lagrange to succeed Euler at the Berlin Academy. [AMM 34(1927), p 128]

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1775 Benjamin Franklin became Postmaster-General of the United States *TIS

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1800 Caroline Herschel gets annual salary from George III. "William Herschel was paid £200 in annual salary as King’s Astronomer. His sister Caroline was paid £50 to act as his assistant, making her the first professional female astronomer.
A note from Herschel’s wife Mary says that the handwriting is that of King George III himself. " *sciencemuseum.org.uk

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1895 Marie Sklodovska became Marie(CURIE) (1867-1934) entered the Sorbonne in 1891 and came in first in physics in 1893 and second in mathematics in 1894. She first lived with her sister and brother-in-law at 92 Avenue Jean-Jaurès, La Villette, 19e. Married Pierre Curie (1859-1906), a teacher at the École de Physique et Chimie, 42 Rue Lhomond, on 26 Jul 1895
In 1896, Marie Curie decided to investigate Henri Becquerel's discovery of the radioactivity of uranium, as a research topic for her doctoral thesis. Pierre subsequently followed her into research into radioactivity (1898), for which they were later awarded a Nobel Prize. In 1897 she gave birth to a daughter, Irène who later married Frédéric Joliot and became Irène Joliot-Curie (1926). With her husband, she continued the family's work into radioactivity. They, too, received a Nobel Prize *TIS

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1976 Kenneth Appel and Wolfgang Haken of the University of Illinois communicated their solution to the Four Color Problem to the Bulletin of the American Mathematical Society. The solution used over 1000 hours of computer calculation. *VFR

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1989 A federal grand jury indicts Cornell University student Robert Tappan Morris, Jr. for releasing a computer virus, making him the first person to be prosecuted under the 1986 Computer Fraud and Abuse Act in the United States. *Wik

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2009 An event was held at Syon House, West London, to celebrate the 400th anniversary of Thomas Harriot's first observations of the moon. This event, Telescope400, included the unveiling of a plaque to commemorate Harriot by Lord Egremont. The plaque can now be seen by visitors to Syon House, the location of Harriot's historic observations. His drawing made 400 years earlier is believed to be based on the first ever observations of the moon through a telescope. The event (sponsored by the Royal Astronomical Society) was run as part of the International Year of Astronomy (IYA).
The original documents showing Harriot's moon map of c. 1611, observations of Jupiter's satellites, and first observations of sunspots were on display at the Science Museum, London, from 23 July 2009 until the end of IYA. *Wik

The Thomas Harriot plaque in the grounds of Syon House (W. London)

*Wik

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BIRTHS

1271 Zhao Youqin's name is sometimes written as Chao Yu-Chhin or Chao Yu-Ch'in. (July 26, 1271, Poyang, China— c. 1335, Longyou Mountains, Zhejiang province) He was born at a time of conflict when the Mongol leader Kublai Khan began attacking the Song Dynasty of China. The Song imperial family surrendered in 1276 and the last of the resistance was crushed in 1296. One source suggests that Zhao was injured in the fighting surrounding these dramatic events. When he was a young man he learnt astronomy and obtained a secret book on alchemy from a Daoist master. He joined the northern branch of the Quanzhen sect of Daoism and became a Daoist hermit, spending ten years writing a commentary on the Book of Changes . No trace of this commentary has survived. He later became the patriarch of the Quanzhen (Complete Perfection) School of Song-Yuan Daoism, ordained by the preceding patriarch, Zhang Mo.
Zhao Youqin was skilled in a large range of topics. He was an expert in astronomy, mathematics and physics, with particular skills in optics. He was also, however, a religious philosopher and a specialist in alchemy. Before he died he gave a copy of the manuscript of his book Ge xiang xin shu, to his disciple Zhu Hui. The manuscript was passed from Zhu Hui to Zhang Jun who published the work. *SAU

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1852 Francis Robbins Upton (1852 in Peabody, Massachusetts – March 10, 1921 in Orange, New Jersey) was an American physicist and mathematician.
Upton graduated from Phillips Academy, Andover in 1870. He studied at Bowdoin College in Brunswick, Maine, at Princeton University where he received his M.S., and in Berlin, where he worked together with Hermann von Helmholtz.
In 1878, he joined the laboratory of Thomas Alva Edison in Menlo Park, New Jersey. There he dealt with technical problems in a mathematical way, including electric light, the watt-hour meter, and large dynamos. In October 1879, the first electric light was presented to the public. He was partner and general manager of the Edison Lamp Works, which he founded together with Edison in 1880. Upton published articles in Scribner's Monthly and Scientific American. Since 1958, the Princeton University has had the Francis Upton Graduate Fellowships.
In 1890, Upton patented the first electric fire alarm and detector along with a Mr. Fernando J. Dibble, an accomplishment of his which is often overlooked, stemming most probably from a typographical error that labels the device a "Portable Electric Tire-Alarm." (Google Books; U.S. Congressional Serial Set).*Wik

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1863 Paul Walden (26 July 1863 – 22 January 1957) was a Latvian chemist who, while teaching at Riga, discovered the Walden inversion, a reversal of stereochemical configuration that occurs in many reactions of covalent compounds (1896). Due to this discovery, Walden's name is mentioned almost in all textbooks on organic chemistry published throughout the world. Walden revealed autoracemization and put the foundations to electrochemistry of nonaqueous solutions. Walden is also known for Walden's rule, which relates the conductivity and viscosity of nonaqueous solutions.*TIS

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1902 Stanisław Gołąb (July 26, 1902 – April 30, 1980) was a Polish mathematician from Kraków, working in particular on the field of affine geometry.
In 1932, he proved that the perimeter of the unit disc can take any value in between 6 and 8, and that these extremal values are obtained if and only if the unit disc is an affine regular hexagon resp. a parallelogram. 

In mathematics, affine geometry is what remains of Euclidean geometry when ignoring (mathematicians often say "forgetting") the metric notions of distance and angle.*Wik

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1903 Kurt Mahler (26 July 1903, Krefeld, Germany – 25 February 1988, Canberra, Australia) was a mathematician and Fellow of the Royal Society. Mahler proved that the Prouhet–Thue–Morse constant and the Champernowne constant 0.1234567891011121314151617181920... are transcendental numbers.
He was a student at the universities in Frankfurt and Göttingen, graduating with a Ph.D. from Johann Wolfgang Goethe University of Frankfurt am Main in 1927. He left Germany with the rise of Hitler and accepted an invitation by Louis Mordell to go to Manchester. He became a British citizen in 1946.
He was elected a member of the Royal Society in 1948 and a member of the Australian Academy of Science in 1965. He was awarded the London Mathematical Society's Senior Berwick Prize in 1950, the De Morgan Medal, 1971, and the Thomas Ranken Lyle Medal, 1977. *Wik

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1907 Nachman Aronszajn (26 July 1907, Warsaw, Poland – 5 February 1980 Corvallis, Oregon, U.S) was a Polish American mathematician of Ashkenazi Jewish descent. Aronszajn's main field of study and expertise was mathematical analysis. He also contributed to mathematical logic.
He received his Ph.D. from the University of Warsaw, in 1930, in Poland. Stefan Mazurkiewicz was his thesis advisor. He also received a Ph.D. from Paris University, in 1935; this time Maurice Fréchet was his thesis advisor. He joined the Oklahoma A&M faculty, but moved to the University of Kansas in 1951 with his colleague Ainsley Diamond after Diamond, a quaker, was fired for refusing to sign a newly-instituted loyalty oath. Aronszajn retired in 1977. He was a Summerfield Distinguished Scholar from 1964 to his death.
He introduced, together with Prom Panitchpakdi, the injective metric spaces under the name of "hyperconvex metric spaces". Together with Kennan T. Smith, Aronszajn offered proof of the Aronszajn–Smith theorem. Also, the existence of Aronszajn trees was proven by Aronszajn; Aronszajn lines, also named after him, are the lexicographic orderings of Aronszajn trees.
He also has a fundamental contribution to the theory of reproducing kernel Hilbert space, the Moore–Aronszajn theorem is named after him. *Wik

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1926 Joseph F. Engelberger (New York City, July 26, 1925 - ) American engineer who, with George Devol, developed the first industrial robot in the United States, the Unimate, in the 1950's. Engelberger is often referred to as the "Father of Robotics." When he and his partner founded Unimation in 1956, the company was the first major manufacturer of industrial robotic arms in the U.S. By 1962, they had installed their first industrial robots at the auto manufacturer, General Motors. *TIS

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1945 Karl Sigmund (born July 26, 1945) is a Professor of Mathematics at the University of Vienna and one of the pioneers of evolutionary game theory.

Sigmund was head of the Institute of Mathematics at the University of Vienna from 1983 to 1985, managing editor of the scientific journal Monatshefte für Mathematik from 1991 to 2001, vice-president (1995 to 1997) and president (1997 to 2001) of the Austrian Mathematical Society, corresponding member (1996) and full member (1999) of the Austrian Academy of Sciences, and member of the Leopoldina (2003). He has also given many plenary lectures, for instance at the International Congress of Mathematicians in 1998. He was awarded the Gauss Lectureship in 2003.

In 2010 he received an honorary doctorate (Doctor Philosophiae Honoris Causa) from the University of Helsinki. In 2012 he received the Isaacs Award.

During the last decade, Sigmund became increasingly interested in the history of mathematics and in particular, the Vienna Circle. He co-edited the mathematical works of Hans Hahn and Karl Menger and organised in 2001 an exhibition on the exodus of Austrian mathematicians fleeing the Nazis and in 2006 an exhibition on Kurt Gödel. From 2003 to 2005 he was vice-president of the Austrian Science Fund (FWF).

Because of his intimate knowledge of the Vienna Circle, Sigmund was invited to the Illinois Institute of Technology to speak at the inaugural Remembering Menger event on April 9, 2007.

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1969 Andrei Yuryevich Okounkov (born July 26, 1969 - ) is a Russian mathematician who works on representation theory and its applications to algebraic geometry, mathematical physics, probability theory and special functions. He is currently a professor at the Columbia University and the academic supervisor of HSE International Laboratory of Representation Theory and Mathematical Physics.

He has worked on the representation theory of infinite symmetric groups, the statistics of plane partitions, and the quantum cohomology of the Hilbert scheme of points in the complex plane. Much of his work on Hilbert schemes was joint with Rahul Pandharipande.

Okounkov, along with Pandharipande, Nikita Nekrasov, and Davesh Maulik, has formulated well-known conjectures relating the Gromov–Witten invariants and Donaldson–Thomas invariants of threefolds.

In 2006, at the 25th International Congress of Mathematicians in Madrid, Spain, he received the Fields Medal "for his contributions to bridging probability, representation theory and algebraic geometry." In 2016, he became a fellow of the American Academy of Arts and Sciences.

DEATHS

1925 Gottlob Frege (8 November 1848 – 26 July 1925) died. He was the greatest logician since Aristotle. *VFR (Friedrich Ludwig) Gottlob Frege was a German mathematician and logician, founder of modern symbolic logic and first to put forward the view that mathematics is reducible to logic. He extended Boole's work by inventing logical symbols (symbols for "or"," if-then", etc.) that improved on the syllogistic logic it replaced. He also worked on general questions of philosophical logic and semantics. His theory of meaning, based on makig a distinction between what a linguistic term refers to and what it expresses, is still influential. Frege tried to provide a rigorous foundation for mathematics on the basis of purely logical principles, but abandoned the attempt when Bertrand Russell, on whose work he had a profound influence, pointed out a paradox that made the system inconsistent. *TIS

In mathematical logic, Russell's paradox (also known as Russell's antinomy) is a set-theoretic paradox published by the British philosopher and mathematician Bertrand Russell in 1901.[1][2] Russell's paradox shows that every set theory that contains an unrestricted comprehension principle leads to contradictions.[3] The paradox had already been discovered independently in 1899 by the German mathematician Ernst Zermelo.[4] However, Zermelo did not publish the idea, which remained known only to David Hilbert, Edmund Husserl, and other academics at the University of Göttingen. At the end of the 1890s, Georg Cantor – considered the founder of modern set theory – had already realized that his theory would lead to a contradiction, as he told Hilbert and Richard Dedekind by letter.  *Wik

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1941 Henri L´eon Lebesgue (June 28, 1875 – July 26, 1941) French mathematician who developed a theory of integration, now known by his name. By extending the work of Camille Jordan and Émile Borel on the Riemann integral, Lebesgue provided a generalization that solved many of the difficulties in using Riemann's theory of integration. Lebesque provided a foundation for subsequent development of integration theory and its further application in calculus, curve rectification and theory of trigonometric theory. He also contributed in several fields of mathematics, including set theory, caluclus of variation and function theory*TIS

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1942 Georg Alexander Pick (August 10, 1859 – July 26, 1942) was an Austrian mathematician. He died in the Theresienstadt concentration camp. Today he is best known for Pick's formula for determining the area of lattice polygons. He published it in an article in 1899; it was popularized when Hugo Dyonizy Steinhaus included it in the 1969 edition of Mathematical Snapshots. Pick headed the committee at the (then) German university of Prague which appointed Albert Einstein to a chair of mathematical physics in 1911. Pick introduced Einstein to the work of Italian mathematicians Gregorio Ricci-Curbastro and Tullio Levi-Civita in the field of absolute differential calculus, which later in 1915 helped Einstein to successfully formulate General relativity.*Wik  My article Pick's Theorem, Some History is here.

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1955 Raymond C Archibald (Colchester County, Nova Scotia, October 7, 1875 - July 26, 1955, in Sackville, New Brunswick) studied in Canada, at Harvard and at Strasbourg. He spent most of his career at Brown University in Rhode Island. His main interests were in the History of Mathematics. *SAU

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1977 Oskar Morgenstern (January 24, 1902 – July 26, 1977) German-American economist and mathematician who popularized "game theory" which mathematically analyzes behaviour of man or animals in terms of strategies to maximize gains and minimize losses. He coauthored Theory of Games and Economic Behavior (1944), with John von Neumann, which extended Neumann's 1928 theory of games of strategy to competitive business situations. They suggested that often in a business situation ("game'), the outcome depends on several parties ("players"), each estimating what all of the others will do before determining their own strategy. Morgenstern was a professor at Vienna University, Austria, from 1931 until the Nazi occupation in 1938), when he fled to America and joined the faculty at Princeton University. His later publications included works on economic prediction and aspects of U.S. defence.*TIS

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1984 George Horace Gallup (November 18, 1901 – July 26, 1984) was an American pioneer of survey sampling techniques and inventor of the Gallup poll, a successful statistical method of survey sampling for measuring public opinion.
Gallup was born in Jefferson, Iowa, the son of George Henry Gallup, a dairy farmer. His higher education took place at the University of Iowa. He served as a journalism professor at Drake and Northwestern for brief periods. In 1932 he moved to New York City to join the advertising agency of Young and Rubicam as director of research (later as vice president from 1937 to 1947). He was also professor of journalism at Columbia University, but he had to give up this position shortly after he formed his own polling company, the American Institute of Public Opinion (Gallup Poll), in 1935.
In 1936, his new organization achieved national recognition by correctly predicting, from the replies of only 50,000 respondents, that Franklin Roosevelt would defeat Alf Landon in the U.S. Presidential election. This was in direct contradiction to the widely respected Literary Digest magazine whose poll based on over two million returned questionnaires predicted that Landon would be the winner. Not only did Gallup get the election right, he correctly predicted the results of the Literary Digest poll as well using a random sample smaller than theirs but chosen to match it.
Twelve years later, his organization had its moment of greatest ignominy, when it predicted that Thomas Dewey would defeat Harry S. Truman in the 1948 election, by five to fifteen percentage points. Gallup believed the error was mostly due to ending his polling three weeks before Election Day.
Gallup died in 1984 of a heart attack at his summer home in Tschingel, a village in the Bernese Oberland of Switzerland. He was buried in Princeton Cemetery. *Wik

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1997 Kunihiko Kodaira (16 March 1915 – 26 July 1997) Japanese mathematician who was awarded the Fields Medal in 1954 for his work in algebraic geometry and complex analysis. Kodaira's work includes applications of Hilbert space methods to differential equations which was an important topic in his early work and was largely the result of influence by Weyl. Through the influence of Hodge, he also worked on harmonic integrals and later he applied this work to problem in algebraic geometry. Another important area of Kodaira's work was to apply sheaves to algebraic geometry. In around 1960 he became involved in the classification of compact, complex analytic spaces. One of the themes running through much of his work is the Riemann-Roch theorem. He won the 1985 Wolf Prize. *TIS

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2000 John Wilder Tukey (June 16, 1915 – July 26, 2000) was an American statistician. He was awarded the IEEE Medal of Honor in 1982 "For his contributions to the spectral analysis of random processes and the fast Fourier transform (FFT) algorithm."
Tukey retired in 1985. He died in New Brunswick, New Jersey Tukey coined many statistical terms that have become part of common usage, but the two most famous coinages attributed to him were related to computer science.
While working with John von Neumann on early computer designs, Tukey introduced the word "bit" as a contraction of "binary digit". The term "bit" was first used in an article by Claude Shannon in 1948.
The term "software", which Paul Niquette claims he coined in 1953, was first used in print by Tukey in a 1958 article in American Mathematical Monthly, and thus some attribute the term to him.
In the fall of 2003 a post to the APStats electronic discussion list from Ron Dirkse pointed out that the Japanese word for statistics, toukei, sounds very much like the name of the famous American statistician John Tukey. Ron Dirkse, who taught at the American School in Japan, added that "according to a native speaker the tou means something like 'put together' and the kei is 'measure, calculate or total'. She thought it was interesting that there was a Tukey famous in statistics, but this word pre-dates him by a lot."

Other terms credited to Tukey below are from http://www.stat.berkeley.edu/~brill/Papers/life.pdf That site Also includes a list of his honors, and Ph.D. students
alias (in time series)
ANOVA
badmandments
bagplot
batch
bispectrum
bit
biweight
bland distribution
borrowing strength
boxplot
cepstrum
coco
complex demodulation
confirmatory data analysis (CDA).

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2004 - William A. Mitchell died (October 21, 1911 – July 26, 2004). Mitchell was an American food chemist who was the inventor of Pop Rocks, instant Jell-O, Cool Whip and the orange drink, Tang. While working for the General Foods Corporation, he received over 70 patents.
Pop Rocks were the center of an urban legend where the kid from the Life cereal commercials died when he ate the candy and washed it down with a cola making his stomach explode. General Foods countered the claims with an ad campaign in 45 major publications and 50,000 letters to school principals. Mitchell toured the country to show people that Pop Rocks weren't dangerous. *Science History

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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

Things I Learned on the Road-II

 

Things I Learned on the Road (and long afterward, at home)

Some notes from a trip a few years ago with some updates from recent readings.... enjoy (or if this is your second time, re-enjoy)
Newsflash!! Spanish Moss is NOT Spanish...AND (wait for it.....) it is NOT moss... talk about bad names... The French gave it the "Spanish" name as an insult???? 

Guess you had to be there. Probably an old Monty Python skit about that, "Your Moss is Spanish and your Mother smells of Elderberries!!!". Ok, and the moss part, NOPE... its an epiphitic (gets its food from the air) bromeliad (cousin of the pineapple). Now you know

I also was reminded that people do things that seem really strange. In the middle of the road in Enterprise Alabama, there is a statue to the Boll Weevil. Now if you are really a city child and know nothing of the agricultural history of the south, the weevil wiped out many cotton farmers in the south around the beginning of the 20th century. The idea of a monument to the weevil in Alabama would seem like a giant grasshopper in Salt Lake City, Utah.  (Just a few weeks ago in 2023 a lot of folks in Salt Lake area may have been hoping for another seagull miracle when the National Weather Service reported a swarm of grasshoppers on their radar screen.  After a day of investigation, the culprit turned out to be the chaff from the flyboys out of Nellis AFB) 

Ok, So a few years later I came across a reason for this at the Futility Closet blog by Greg Ross.  It seems that, after the weevil's wiped out all the cotton crops for several years in a row, "local businessman H.M. Sessions convinced indebted farmer C.W. Bastion to try planting peanuts instead of cotton. When Bastion produced 8,000 bushels that year, neighboring farmers followed suit, and in 1917 Coffee County brought forth the largest peanut harvest in the nation.
Because the new, diversified crops proved more profitable than cotton, in 1919 local businessman Roscoe Fleming proposed dedicating a statue to the pest that had proven a “herald of prosperity,” and an $1,800 classical statue was commissioned from an Italian sculptor. Thirty years later, one Luther Baker fashioned a large weevil to place atop her outstretched arms. Might as well be explicit."  --And now you know, as Paul Harvey would say, ....

I also continued my road heroics on Jekyll Island (which used to be called Jeykl Island, but someone thought the extra L would be better ). I saved a Loggerhead Turtle and set him free. Ok, I didn't do it all by myself. The Georgia Sea Turtle association was releasing a ten year old (about 150 pounds) that had been kept in the Georgia Aquarium since its egg-ship. I did happen to be in the crowd watching as Dylan, that was his name, went free. He seemed to need a little encouragement as he turned back to shore several times. Eventually prompted by the workers in the waters urging he swam out to sea. Perhaps he was also encouraged by the shouting on shore as the crowd yelled "DIll - Enn.. Dill Enn... repeatedly, especially if he was as confused as I was at first. I thought I had fallen in with gourmets of the turtle soup variety yelling "Kill him, kill him..' eventually I got it straight, and hope Dylan also knew we were NOT trying to have him for supper.

More stuff I learned, don't explain palindromes while driving through Elba, Alabama. As I came into town the name of the town reminded me of one of the first palindromes I ever leaned (OK, second, the first was Madam I'm Adam.. read it backwards if you don't know what a palindrome is); Able was I ere I saw Elba. In math, we call numbers like 121 or 1331 or 14641 (surely you recognize the powers of 11) palindromic numbers. We even refer to a polynomial like 1x²+2x+1 as palindromic (look at the coefficients). As I was making sure my wife understood, I saw flashing lights in the rear view mirror... apparently the speed through town was only 25 mph and I was, as the kind officer explained holding thumb and finger an inch apart, "A little over." It was Sunday Morning, and in the spirit of Christian charity, he let me off with a warning.... Thank goodness I was not in Georgia.. I might still be rotting in Macon County Correctional Institute for Out of state drivers.

On This Day in Math - July 25

 

Teacher: How many times can you subtract 7 from 83, and what is left afterwards?
Student: You can subtract it as many times as you want, and it leaves 76 every time. ~Author Unknown

The 206th Day of the Year
206 is the lowest positive integer (when written in English) to employ all of the vowels once only. (This seems to require the use "two hundred AND six" which I really dislike. What would be, or is there a, first without this "and"?) (Michael King ‏@processr suggested "5000 fIvE thOUsAnd".

206 is Sum of the lengths of the first runs in all permutations of [1, 2, 3, 4, 5] (for example, the first run of the permutation 23541 is three.)

206 is the sum of 39, and the 39th prime, 167.

There are 206 bones in the typical adult human body. (I suppose all those spineless people folks talk about have well under 200!)

206 is the 36th year date for which n^2 + 1 is prime. It's also the 59th day for which n^2 + n + 1 is prime. Am I the only one who thought the second would be more unusual?

204, 206 and 208 are all the sum of a square and a cube. 206= 5^3 + 9^2. It seems that there are an infinite numbers of three consecutive integers that are such sums. 126, 127, 128 and 129 is a string of four such sums

There are 206 partitions of 26 into four parts

The sum of the divisors of 14 and 15 are equal. I mention that here because the next occurrence of such an incident is 206 and 207 which both sum to 312.

206 is Sum of the lengths of the first runs in all permutations of [1, 2, 3, 4, 5] (for example, the first run of the permutation 23541 is three.)
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Here for More Math Facts for every Math Date

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EVENTS

1610 Galileo first observed the rings of Saturn through a telescope without realizing what they were.Galileo first turned his telescope on Saturn on 25 July 1610 and it appeared as three bodies (his telescope was not good enough to show the rings but made them appear as lobes on either side of the planet). Continued observations were puzzling indeed to Galileo as the bodies on either side of Saturn vanished when the ring system was edge on. *SAU

The full set of rings, imaged as Saturn eclipsed the Sun from the vantage of the Cassini orbiter,

*Wik

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1741 Euler arrives in Berlin after a one month sea and land journey from St. Petersburg to become director of  Mathematics at Frederick the Great's newly formed Academy of Science. Having endured the political intrigue and brutal regime of Princess Anna, Euler had avoided the Political scene by immersing himself in work.  Frederick's mother, Sophia Dorothea, complained to Euler because he was so laconic.  Euler's reply was, "Madam, I have just come from a country where every person who spoke was hanged." *John Derbyshire, Prime Obsession, pg 59-60

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 1783 Founding of the Royal Academy of Science in Turin.*VFR Lagrange helped found and was a major contributor to the scientific society of Turin, which would become the Royal Academy of Science of Turin. A main objective of this society was their journal, the Mélanges de Turin.

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1807 Gauss named Professor of Astronomy and director of the new observatory in Gottingen. *VFR

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In 1837, the five-needle telegraph was demonstrated by English inventors, Charles Wheatstone and William Fothergill Cooke. They ran a six-wire telegraph line 2.4-km from Euston to Camden Town along the Great Western Railway Company railway track. They successfully transmitted and received messages. Wheatstone provided the technological skill and is better remembered in the history of the telegraph while Cooke had the business acumen. This first patent (1837) was impractical because the code used simultaneous combinations of five keys, and so was rather cumbersome, limited to only twenty letters (J, C, Q, U, X and Z were omitted). By 1845, they patented the more important single-needle electric telegraph.*TIS

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1925 The “Monkey Trial” of John T. Scopes began in Dayton, Tennessee. Clarence Darrow defended him. The prosecution, conducted by William Jennings Bryan, presented a strong case, and he was convicted of violating a state law prohibiting the teaching of evolution. Although the law was later overturned, this case provided a strong blow to science education. Scopes was not a biologist and never taught evolution. Rather he was a mathematics and physics teacher who volunteered to stand trial to furnish a test case.*VFR
The trial ran for 12 days. A local school teacher, John Scopes, was prosecuted under the state's Butler Act, but was supported by the American Civil Liberties Union. This law, passed a few months earlier (21 Mar 1925) prohibited the teaching of evolution in public schools. The trial was a platform to challenge the legality of the statute. Local town leaders,(wishing for the town to benefit from the publicity of the trial) had recruited Scope to stand trial. He was convicted (25 Jul) and fined $100. On appeal, the state supreme court upheld the constitutionality of the law but acquitted Scopes on the technicality that he had been fined excessively. The law was repealed on 17 May 1967. *TIS

*Wik

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1976 Viking 1 orbiter took the infamous "Face on Mars" photo. "There is a hill on Mars that is roughly a kilometer across. It was first imaged by the Viking orbiter in the 1970s. It looks like a face. Richard Hoagland jumped on this, saying it didn't just look like a face, it was a face, carved by aliens for unknown reasons. He made this claim over and over, and then images taken later by probes with higher resolution cameras showed it didn't look much like a face at all. Hoagland then claimed that a) they botched the image, making it look less like a face, and b) he had predicted all along it wouldn't look like a face when better images were taken." *Phil Plait, Bad Astronomy

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C
BIRTHS

1573 Christoph Scheiner SJ (25 July 1573 (or 1575) – 18 July 1650) was a Jesuit priest, physicist and astronomer in Ingolstadt. In 1603, Scheiner invented the pantograph, an instrument which could duplicate plans and drawings to an adjustable scale. Later in life he would invent a sunspot viewing appartus. In 1611, Scheiner observed sunspots; in 1612 he published the "Apelles letters" in Augsburg. Marcus Welser had the first three Apelles letters printed in Augsburg on January 5, 1612. They provided one of many reasons for the subsequent unpleasant argument between Scheiner and Galileo Galilei. *Wik Thus, in 1614, Galileo found himself in an unresoved dispute over priority with a mean and determined Jesuit. The fight was to grow meaner in subsequent years. It would play a major role in Galileo's Inquisitional trial eighteen years later. *James Reston, Jr., Galileo: A Life
Thony Christie responded that, "The Reston quote is a historical perversion. If anybody was mean and determined, it was Galileo, especially mean!"  Christie has a nice post about Scheiner  that describes his view of the dispute with Galileo, as well as some of his many other achievements, and says, "Scheiner’s work on vision contains many other important discoveries on the physiology of the eye making him alongside Kepler, Descartes, Gregory and Huygens to one of the important optical researchers of the seventeenth century."

*Linda Hall Org

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1808 Johann Benedict Listing (25 July 1808 – 24 December 1882) 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 phenomenona", "nodal points", "homocentric light", "telescopic system", " geoid" ...he coined "one micron" for the millionth of a metre ...*SAU

Listing was attending mathematics courses given by Gauss and he was quickly spotted by Gauss as being both a very able and a very hard working student. Gauss invited him to join his circle of friends who included Weber. *Wik

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1825 Henry Wilbraham (July 25, 1825 – February 13, 1883) was an obscure English mathematician. His only noteworthy accomplishment was discovering and explaining the Gibbs phenomenon nearly fifty years before J. Willard Gibbs did. Gibbs and Maxime Bôcher, as well as nearly everyone else, were unaware of Wilbraham's work on the Gibbs phenomenon.*Wik

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1857 Frank (Julian) Sprague (July 25, 1857 in Milford, Connecticut - October 25, 1934) was an engineer, inventor, and a pioneer in electric railway transportation. He started his career at sea in the U.S. Navy (1878). Later, he worked at the Brooklyn Navy Yard making plans for incadescent electric lamps on navy vessels, which led to joining Edison at Menlo Park (1883) He formed the Sprague Electric Railway and Motor Company in 1884, and became known as "the father of electric railway traction." when he installed the first U.S. electric trolley system (Richmond, Va., 1887). Edison took over this company in 1892. Sprague earned many patents, many for railway applications and diverse ideas such as electric toasters, electric signs, electric elevators and naval weaponry.*TIS

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1901 Richard Gwilt was an actuary who worked for various Edinburgh insurance companies. He was a Fellow of the Faculty of Actuaries and of the Institute of Actuaries. *SAU

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1915 Ivan Petrovich Egorov born the prominent Soviet geometer, *VFR It seems he died in 1990 but I can't find exact information.

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1920 Rosalind Franklin (25 July 1920 – 16 April 1958) was an English scientist who contributed to the discovery of the molecular structure of deoxyribonucleic acid (DNA), a constituent of chromosomes that serves to encode genetic information. Beginning in 1951, she made careful X-ray diffraction photographs of DNA, leading her to suspect the helical form of the molecule, at least under the conditions she had used. When Watson saw her photographs, he had confirmation of the double-helix form that he and Crick then published. She never received the recognition she deserved for her independent work, but had died of cancer four years before the Nobel Prize was awarded to Crick and Watson.*TIS

*Wik

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DEATHS

1980 Euphemia Lofton Haynes (September 11, 1890 - July 25, 1980) After graduating from Washington D.C. Miner Normal School with distinction, she went on to earn an undergraduate mathematics major (and psychology minor) from Smith College in 1914. In 1917 she married Harold Appo Haynes.
Haynes pursued graduate studies in mathematics and education at the University of Chicago, earning a masters degree in education in 1930. She continued her graduate work in mathematics at the Catholic University of America where in 1943 she became the first African-American woman to earn a Ph.D. in mathematics. Her dissertation on "The Determination of Sets of Independent Conditions Characterizing Certain Special Cases of Symmetric Correspondences" was written under the supervision of Professor Aubrey Landrey.
Euphemia Haynes devoted her life to education in the Washington, D.C. area for forty-seven years, including teaching mathematics at Armstrong High School and Dunbar High School. She became a professor of mathematics at Miner Teachers College in 1930 where she established the mathematics department and served as chair of the Division of Mathematics and Business Education (in 1955 Minor Teachers College and Wilson Teachers College united to form the District of Columbia Teachers College.) From July 1966 to July 1967, Haynes served as the first woman to chair the District of Columbia School Board. She played a central role in the integration of the DC public schools. Upon her death, she left $700,000 to the Catholic University of America which was used to establish the Euphemia Lofton Haynes Chair in the Department of Education and to support a student loan fund in the School of Education. *ASC

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1987 Charles Stark Draper (October 2, 1901 – July 25, 1987) American aeronautical engineer, educator, and science administrator who earned degrees from Stanford, Harvard, and MIT then, in 1939, became head of MIT's Instrumentation Laboratory, which was a center for the design of navigational and guidance systems for ships, airplanes, and missiles from World War II through the Cold War. He developed gyroscope systems that stabilized and balanced gunsights and bombsights and which were later expanded to an inertial guidance system for launching long-range missiles at supersonic jet targets. He was "the father of inertial navigation." The Project Apollo contract for guiding man and spacecraft to the moon was also placed with the Instrumentation Lab.*TIS

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1992 Ralph Philip Boas Jr. (August 8, 1912 – July 25, 1992) was a mathematician, teacher, and journal editor. He wrote over 200 papers, mainly in the fields of real and complex analysis.

After postdoctoral studies at Princeton University with Salomon Bochner, and then the University of Cambridge in England, he began a two-year instructorship at Duke University, where he met his future wife, Mary Layne, also a mathematics instructor at Duke. They were married in 1941, and when the United States entered World War II later that year, Boas moved to the Navy Pre-flight School in Chapel Hill, North Carolina. In 1942, he interviewed for a position in the Manhattan Project, at the Los Alamos National Laboratory, but ended up returning to Harvard to teach in a Navy instruction program there, while his wife taught at Tufts University.

Beginning when he was an instructor at Duke University, Boas had become a prolific reviewer for Mathematical Reviews, and at the end of the war he took a position as its full-time editor. In the academic year 1950–1951 he was a Guggenheim Fellow.Boas, Frank Smithies, and colleagues were behind the 1938 paper A Contribution to the Mathematical Theory of Big Game Hunting published in the American Mathematical Monthly under the pseudonym H. Pétard (referring to Hamlet's "hoist by his own petard"). The paper offers short spoofs of theorems and proofs from mathematics and physics, in the form of applications to the hunting of lions in the Sahara desert. One "proof" parodies the Bolzano–Weierstrass theorem:

The Bolzano–Weierstrass Method. Bisect the desert by a line running N–S. The lion is either in the E portion or in the W portion; let us suppose him to be in the W portion. Bisect this portion by a line running E–W. The lion is either in the N portion or in the S portion; let us suppose him to be in the N portion. We continue this process indefinitely, constructing a sufficiently strong fence about the chosen portion at each step. The diameter of the chosen portions approaches zero, so that the lion is ultimately surrounded by a fence of arbitrarily small perimeter.

The paper became a classic of mathematical humor and spawned various follow-ons over the years with theories or methods from other scientific areas adapted to hunting lions.

The paper and later work is published in Lion Hunting and Other Mathematical Pursuits : A Collection of Mathematics, Verse, and Stories by the Late Ralph P. Boas Jr., edited by Gerald L. Alexanderson and Dale H. Mugler, ISBN 0-88385-323-X. Various online collections of the lion hunting methods exist too.

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1993 Vincent Joseph Schaefer (July 4, 1906 – July 25, 1993) U.S. chemist whose research in meteorology and weather control introduced cloud seeding. He worked on the physics of precipitation at the General Electric (GE) Research Laboratory in Schenectady, New York. Having discovered a method of producing a snowstorm under laboratory conditions, he proved the same was possible outdoors. On 13 Nov 1946, he flew over Mount Greylock in Massachusetts, successfully seeding clouds with pellets of dry ice (solid carbon dioxide) to produce the first snowstorm initiated by man. Later, he became founder and director of Atmospheric Sciences Research Center at State University of New York in Albany. *TIS

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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 - July 24

In mathematics the art of proposing a question 

must be held of higher value than solving it.

~Goerg Cantor


Today is the 205th day of the year; there are 205 pairs of twin primes less than ten thousand. *Number Gossip

Every number greater than 205 is the sum of distinct primes of the form 6n + 1. *Prime Curios

205 is the number of walks of length 5 between any two distinct vertices of the complete graph K_5

205 is the smallest un-primeable odd composite  .  It can not be turned into a prime by changing only one of its digits.  (nice exploration for young students)  

205 = 14^2 + 3^2 = 13^2+6^2

205 = 103^2 - 102^2 = 23^2 - 18^2 The first is from a property of every odd number, the second is from a property of any number greater than 35 that ends in five.

205 = 2 x 41 + 41 + 41 x 2 also 54 + 45 + 7 + 54 + 45. or 99 + 7 + 99

205 is a palindrome in duodecimal (base 12, (151) =1 x 12^2 + 5 x 12 + 1), and in bases 9, 11, 13, and 16.

205 is the smallest un-primeable odd composite  .  It can not be turned into a prime by changing only one of its digits.  (Language fact: A prime which cannot be turned into another prime by changing a single digit is called weakly prime. These are all pretty big, the smallest being 294001.)

205 is a semi-prime, 5 x 41.  It is also a reversible semi-prime, or emirpimes, since it's reversal, 502 = 2 x 251, is also a semi-prime

Here for More Math Facts for every Math Date

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EVENTS

In 1673, Edmund Halley entered Queen's College, Oxford, as an undergraduate. Halley had attended the prestigious St. Paul's school, where in 1671, he was appointed captain, a position resembling today's student body president. He was an excellent student, and by the time he entered Queen's College, Oxford. At this young age, Halley already possessed, "... the basic facts and computations not only of navigation but also those which the practical astronomer is concerned when he sets about the delicate task of measuring the positions of celestial bodies in the sky," according to Colin Ronan in his book Edmond Halley: genius in eclipse *TIS

*Wik

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1860 Yale University authorized the granting of Doctor of Philosophy degrees. The first such degrees in the U.S. were awarded in 1861 by Yale to Eugene Schuyler, James Morris Whiton, and Arthur Williams Wright. [Kane, p. 215] *VFR  

Arthur Williams Wright (September 8, 1836 – December 19, 1915) was an American physicist. Wright spent most of his scientific career at Yale University, where he received the first science Ph.D. awarded outside of Europe. His research, which ranged from electricity to astronomy, produced the first X-ray image and experimented with Röntgen rays. He also proved instrumental in securing funding for the first dedicated physics laboratory building in the United States, the Sloane Physical Laboratory.

Eugene Schuyler (February 26, 1840 – July 16, 1890)[1] was a nineteenth-century American scholar, writer, explorer and diplomat. Schuyler was one of the first three Americans to earn a Ph.D. from an American university;[2] and the first American translator of Ivan Turgenev and Lev Tolstoi. He was the first American diplomat to visit Russian Central Asia, and as American Consul General in Istanbul he played a key role in publicizing Turkish atrocities in Bulgaria in 1876 during the April Uprising. He was the first American Minister to Romania and Serbia, and U.S. Minister to Greece.

Whitton, it seems was a language man who wrote several books about languages including , "

• HandboHandbook of Exercises and Reading Lessons for Beginners in Latin

•  (Boston: James Munroe and Company, 1860); First Lessons in Greek: 

• The Beginner’s Companion-Book to Hadley’s Greek Grammar 

• (New York: D. Appleton & Co., 1862, 1863, 1866, 1872, 1881);  

• *Wik

• Arthur William Wright  

• 
  
  
  
  

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1911, American Hiram Bingham discovered the Lost City of the Incas, Vilcapampa (now called Machu Picchu), where the last Incan Emperors found refuge from the conquistadors.*TIS

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1950, the first successful rocket launch from Cape Canaveral took place. "Bumper" No. 8 was a captured German V-2 rocket with the payload replaced by another rocket 700-pound Army-JPL Wac Corporal rocket on top. It was fired from Long-Range Proving Ground at Cape Canaveral. The first-stage V-2 climbed 10 miles, separated from the second-stage Corporal which traveled 15 more miles. (V-2 exploded). A previous attempt on 19 July 1950 of a similar launch was aborted on the pad. 

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1951  John Bardeen notified AT&T Bell Laboratories that he would be leaving the company where, along with Walter Brattain and William Shockley, he had developed one of the most essential components of modern computing: the point-contact transistor.

The transistor replaced vacuum tubes, allowing the size of computers to decrease dramatically while their power increased. Despite this triumph, Bardeen was unhappy with Shockley, whom he felt was limiting his and Brattain's involvement with further refinements to the transistor. Bardeen took a position at the University of Illinois at Urbana-Champaign. *CHM

*CHM

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1991, a University of Manchester scientist announced the finding a planet outside of solar system. Andrew G. Lyne of the University of Manchester subsequently retracted his claim for a planet around pulsar PSR 1829-10 at the Jan 1992 meeting of the American Astronomical Society in Atlanta. He said that the modulation of radio waves coming from the pulsar was caused not by the presence of a planet but was in fact an artifact of the Earth's motion around the Sun. That possibility that had been considered but then discounted in earlier studies of the data.*TIS

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BIRTHS

1786 Joseph Nicolas Nicollet (July 24, 1786 – September 11, 1843), also known as Jean-Nicolas Nicollet, was a French geographer, astronomer, and mathematician known for mapping the Upper Mississippi River basin during the 1830s. Nicollet led three expeditions in the region between the Mississippi and Missouri Rivers, primarily in Minnesota, South Dakota, and North Dakota.

Before emigrating to the United States, Nicollet was a professor of mathematics at Collège Louis-le-Grand, and a professor and astronomer at the Paris Observatory with Pierre-Simon Laplace. Political and academic changes in France led Nicollet to travel to the United States to do work that would bolster his reputation among academics in Europe. He was elected a member of the American Philosophical Society in 1842.

Nicollet's maps were among the most accurate of the time, correcting errors made by Zebulon Pike, and they provided the basis for all subsequent maps of the American interior. They were also among the first to depict elevation by hachuring and the only maps to use regional Native American placenames. Nicollet's Map of the Hydrographical Basin of the Upper Mississippi was published in 1843, following his death. Nicollet Tower, located in Sisseton, South Dakota is a monument to Nicollet and his work and was constructed in 1991.

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1827 Edward Olney (ALL-nee*) (July 24, 1827 - January 16, 1887) was born in Moreau, Saratoga County, New York. His ancestry can be traced back to Thomas Olney who accompanied Roger Williams in founding the city of Providence and colony of Rhode Island. Benjamin Olney's family moved to Oakland County, Michigan, in 1833 and, a few months later, settled on a farm in Weston, Wood County, Ohio.
Opportunities for formal education on the frontier were sparse, and Olney was largely self-taught. Calloway tells about Edward hiring a neighbor boy to drive the team of oxen on the Olney farm so that he could attend school for six weeks in order to master Day's Algebra. During this time he also ran an arithmetic school at home in the evenings in order to earn the money to pay for his substitute driver.
At age 19, Olney began his career as a teacher in the local elementary schools, while studying mathematics, natural science, and languages on his own. Cajori reports that "though he had never studied Latin, he began teaching it and kept ahead of the class because he 'had more application'." In 1848 Olney was hired as a teacher in the district school at Perrysburg, Ohio. The following year he was named principal of the grammar department in the new Union School. Over the next five years he would become the school's superintendent, marry Miss Sarah Huntington (a teacher at the school), and receive an honorary A. M. degree from Madison University (now Colgate University) in Hamilton, New York. Today there is an Olney School in Lake Township, Wood County, named after him.
In 1853 Olney was appointed Professor of Mathematics at Kalamazoo College, Michigan, where he remained for ten years and established the first mathematics curriculum at that institution. He inspired his colleagues and students alike with "his high Christian aims; his generous, self-sacrificing spirit; his thoroughness in government and discipline; and the inspiration which attended him." Although he insisted that his students recite using exact and correct language, he always tried to simplify the explanations of concepts and processes and make them more understandable. Kalamazoo college later conferred the honorary degree, LL. D. upon him.
In 1863 Olney was named Professor of Mathematics at the University of Michigan, succeeding George P. Williams, whose title was then changed to Professor of Physics. In those days the freshmen at Michigan were taught by inexperienced instructors, but once a week they had to recite for Professor Olney. His reputation for being a stern disciplinarian and a stickler for correct details earned him the nickname "Old Toughy." Nevertheless, he took great pains to see that the poorer students obtained help in making up their deficiencies. According to a former student, G. C. Comstock, "He was not a harsh man, and although the students stood in awe of him, I think that he was generally liked by them."
While he was at Michigan, Professor Olney began writing a series of successful mathematics textbooks for use in both grammar schools and colleges. In many places these displaced the works of such highly regarded authors as Charles Davies and Elias Loomis. Among the titles are: Elements of Arithmetic for Intermediate, Grammar, and Common Schools (1877), A University Algebra (1873), Elementary Geometry (1883), Elements of Trigonometry (1870), and A General Geometry and Calculus (1871) (online). Olney's treatment of calculus was criticized for using infinitesimal methods, but praised for giving "the elegant method, discovered by Prof. James C. Watson [Professor of Astronomy at Michigan], of demonstrating the rule for differentiating a logarithm without the use of series." It is said that Olney preferred geometry to analysis, and when teaching calculus, he would attempt to translate analytical expressions into their geometrical equivalents. This, along with his own struggles in self-education, contributed to his great success as a teacher and textbook author. Edward Olney died on January 16, 1887, after suffering for three years from the effects of a stroke. *David E. Kullman

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1851 Friedrich Hermann Schottky. (24 July 1851 – 12 August 1935) was a German mathematician who worked on elliptic, abelian, and theta functions and invented Schottky groups. He was born in Breslau, Germany (now Wrocław, Poland) and died in Berlin.
He is also the father of Walter H. Schottky, the German physicist and inventor of a variety of semiconductor concepts.*Wik

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1853 Henri-Alexandre Deslandres (July 24, 1853 – January 15, 1948) French astrophysicist who invented a spectroheliograph (1894) to photograph the Sun in monochromatic light (about a year after George E. Hale in the U.S.) and made extensive studies of the solar chromosphere and solar activity. He worked at the Paris and Meudon Observatories. His investigation of molecular spectra produced empirical laws presaging those of quantum mechanics. He observed spectra of planets and stars and measured their radial velocities of, and he determined the rotation rates of Uranus, Jupiter and Saturn (shortly after James E. Keeler).*TIS

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1856 Emile Picard (24 July 1856 – 11 December 1941) born. Picard's mathematical papers, textbooks, and many popular writings exhibit an extraordinary range of interests, as well as an impressive mastery of the mathematics of his time. Modern students of complex variables are probably familiar with two of his named theorems. His lesser theorem states that every nonconstant entire function takes every value in the complex plane, with perhaps one exception. His greater theorem states that an analytic function with an essential singularity takes every value infinitely often, with perhaps one exception, in any neighborhood of the singularity. He also made important contributions in the theory of differential equations, including work on Picard–Vessiot theory, Painlevé transcendents and his introduction of a kind of symmetry group for a linear differential equation, the Picard group. In connection with his work on function theory, he was one of the first mathematicians to use the emerging ideas of algebraic topology. In addition to his path-breaking theoretical work, Picard also made important contributions to applied mathematics, including the theories of telegraphy and elasticity. His collected papers run to four volumes.
Like his contemporary, Henri Poincaré, Picard was much concerned with the training of mathematics, physics, and engineering students. He wrote a classic textbook on analysis and one of the first textbooks on the theory of relativity. Picard's popular writings include biographies of many leading French mathematicians, including his father in law, Charles Hermite.*Wik

He has to be the perfect Stereotype of Every French Inspector in cinema.

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1871 Paul Epstein (July 24, 1871 – August 11, 1939) was a German mathematician. He is known for his contributions to number theory, in particular the Epstein zeta function.
Epstein was raised in Frankfurt where his father was a professor. He received his PhD in 1895 from the University of Strasbourg. From 1895 to 1918 he was a Privatdozent at the University in Strasbourg, which at that time was part of the German Empire. At the end of World War I the city of Strasbourg reverted to France, and Epstein, being German, had to return to Frankfurt.
Epstein was appointed to a non-tenured post at the university and he lectured in Frankfurt from 1919. Later he was appointed professor at Frankfurt. However, after the Nazis came to power in Germany he lost his university position. Because of his age he was unable to find a new position abroad, and finally committed suicide by abusing barbital, fearing Gestapo torture. *Wik

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1888 Dunham Jackson (July 24, 1888, Bridgewater, Massachusetts – November 6, 1946) was a mathematician who worked within approximation theory, notably with trigonometrical and orthogonal polynomials. He is known for Jackson's inequality. He was awarded the Chauvenet Prize in 1935. His book Fourier Series and Orthogonal Polynomials (dated 1941) was reprinted in 2004.
Harold Bacon recalls that Jackson was an inspired writer of limericks. When Bacon purchased Jackson's "The Theory of Approximations" he took it to Jackson's office and requested he sign it, suggesting a limerick. Without any visible prethought Jackson wrote on the flyleaf:

There was a young fellow named Bacon
Whose judgement of books was mistaken
In a moment too rash
He relinquished some cash
And his faith in the Author was shaken

*Steven Krantz, Mathematical Apocrypha Redux

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1923 Christine Mary Hamill (July 24, 1923 – March 24, 1956) was an English mathematician who specialized in group theory and finite geometry. After receiving her Ph.D. at the University of Cambridge in 1951, she was appointed to a lectureship in the University of Sheffield and later was appointed lecturer in the University College, Ibadan, Nigeria.*Wik

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1928  Vera Florence Cooper Rubin (July 23, 1928 – December 25, 2016)  Dr. Rubin was a pioneer, doing paradigm-shifting work on the galaxy rotation problem, which provides major evidence of dark matter. She was born in Philadelphia to Jewish immigrants. She grew up in Philadelphia and Washington, DC. Her interest in astronomy began at an early age and was encouraged by her parents. She was the sole graduate in astronomy in 1948 at 

@Vassar

 College.  Princeton rejected her for their graduate program in astronomy because of her sex--they did not allow women in that program until 1975 (!). She instead attended 

@Cornell

, where she earned her master's degree. Her research was controversial and she had to fight to be allowed to present her work to the American Astronomical Society. 

@AAS_Office

 She fought sexism throughout her education but persisted, earning her PhD from 

@Georgetown

 in 1954. Her dissertation argued galaxies "clump" together, rather than being distributed randomly. She held academic positions and also worked from home while caring for her young children for about 10 years. She worked at  and also broke new ground at Palomar Observatory, where she had to create her own women's restroom. Her collaborator Kent Ford and she are responsible for discovering the Rubin-Ford effect, again highly controversial work. Her courage would ultimately be proven justified when the Rubin-Ford effect was validated. Her work on the rotation curves of spiral galaxies provided evidence of dark matter. (Wikipedia screenshot breaks it down clearly.) Dr. Rubin became the second woman astronomer elected to National Academy of Sciences, and won the National Medal of Science, among myriad honors. The LSST observatory was renamed for her in 2019, in recognition of her achievements and advocacy for women in science. Dr. Rubin died on Christmas, 2016, at age 88, survived by 4 children, all PhDs. Though their father of course also deserves credit, that legacy of education and achievement is remarkable, a testament to the wholeness of a life dedicated to both learning and family. *GWOMaths

DEATHS
1934 Hans Hahn (September 27, 1879 – July 24, 1934) was an Austrian mathematician who is best remembered for the Hahn-Banach theorem. He also made important contributions to the calculus of variations, developing ideas of Weierstrass. *SAU

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1964 Finlay Freundlich (May 29, 1885 – July 24, 1964) was a distinguished German astronomer who worked with Einstein on measurements of the orbit of Mercury to confirm the general theory of relativity. He left Germany to avoid Nazi rule and became the Napier Professor of Astronomy at St Andrews. *SAU

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1974 Sir James Chadwick (20 October 1891 – 24 July 1974) English physicist who received the Nobel Prize for Physics (1935) for his discovery of the neutron. He studied at Cambridge, and in Berlin under Geiger, then worked at the Cavendish Laboratory with Rutherford, where he investigated the structure of the atom. He worked on the scattering of alpha particles and on nuclear disintegration. By bombarding beryllium with alpha particles, Chadwick discovered the neutron - a neutral particle in the atom's nucleus - for which he received the Nobel Prize for Physics in 1935. In 1932, Chadwick coined the name "neutron," which he described in an article in the journal Nature. He led the UK's work on the atomic bomb in WW II, and was knighted in 1945*TIS

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1983 Eberhard Frederich Ferdinand Hopf (April 4, 1902, Salzburg, Austria-Hungary – July 24, 1983, Bloomington, Indiana) was a mathematician and astronomer, one of the founding fathers of ergodic theory and a pioneer of bifurcation theory who also made significant contributions to the subjects of partial differential equations and integral equations, fluid dynamics, and differential geometry. The Hopf maximum principle is an early result of his (1927) which is one of the most important techniques in the theory of elliptic partial differential equations.*Wik

"The modern theory of relativity of Mr Einstein predicts an influence of any field of gravitation upon light passing near to the sun. The gravitation would have, according to the investigation of Einstein, the effect of deflecting the ray of the star, and Mr Einstein asked me if I would try to prove his results by observations." *SAU 

*SAU

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1992 Lillian Rose Vorhaus Kruskal Oppenheimer (October 24, 1898 in New York City – July 24, 1992) was an American origami pioneer. She popularized origami in the West starting in the 1950s, and is credited with popularizing the Japanese term origami in English-speaking circles, which gradually supplanted the literal translation paper folding that had been used earlier. In the 1960s she co-wrote several popular books on origami with Shari Lewis.
She was the mother of three sons William Kruskal(developed the Kruskal-Wallis one-way analysis of variance), Martin David Kruskal(co-inventor of solitons and of surreal numbers), and Joseph Kruskal ( Kruskal's algorithm for computing the minimal spanning tree (MST) of a weighted graph) who all went on to be prominent mathematicians. Her grandson Clyde P. Kruskal (son of Martin) is an American computer scientist,working on parallel computing architectures, models, and algorithms. *Wik

*Origami Heaven

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2005 Sir Richard Doll (28 October 1912 – 24 July 2005) British epidemiologist who was one of the first two researchers to link cigarette smoking to lung cancer, as published in the British Medical Journal in 1950. In the same journal, fifty years later, Doll published (22 Jun 2004) the first research that quantified the damage over the lifetime of a generation, based on a 50-year study of a group of almost 35,000 British doctors who smoked. The study found that almost half of persistent cigarette smokers were killed by their habit, and a quarter died before age 70. Persons who quit by age 30 had normal life expectancy. Even quitting at age 50 saved six more years of life over those who continued smoking. He studied other health effects, such as those caused by asbestos and electromagnetic fields.*TIS

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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