**It is the perennial youthfulness of mathematics itself which marks it off**

**with a disconcerting immortality from the other sciences.**

The 281st day of the year, 281 is a prime and is the sum of the first fourteen prime numbers.

**EVENTS**

**In 1604**, the supernova now called "Kepler's nova" was first sighted in the constellation Ophiuchus, the Serpent Bearer. Johannes Kepler observed it from the time of its appearance as an apparently new star. It encouraged him to write The New Star in 1606.*TIS

**1834**Jakob Steiner appointed extraordinary professor at the University of Berlin, a post he held until his death in 1863. *VFR

**1996**The U.S. Postal Service issued a special "Computer Technology" stamp to mark the 50th anniversary of the ENIAC. In a ceremony at the Army’s Aberdeen Proving Ground, speakers paid tribute to computer pioneers with the image of a brain partially covered by small blocs that contain parts of circuit boards and binary language. The stamp was designed entirely on a computer. A Postal Service news release from Oct. 8 introduced the stamp with a discussion of the ENIAC’s origins: "Long before PCs became standard office equipment and surfing on the information superhighway became a national obsession, calculations were done the ‘old-fashioned way’ by hand. And, as is often the case, it took a war to bring the world into the computer age specifically, the need for the United States Army to rapidly compute ballistic firing tables." *CHM

2008 The Mathematics Library at Notre Dame was rededicated and named for Prof. O. Timothy O’Meara. Prof. O’Meara is a noted Mathematician, who has been on the faculty of the Mathematics Department since 1962, and twice served as its chairman. In 1976 he was named to the Kenna Endowed Chair in Mathematics. He is noted for serving as the first lay Provost of the University, 1978-1996. He is now an emeritus faculty member, but still very active and interested in the library *ND Web Site

**BIRTHS**

1561 Edward Wright (baptised 8 October 1561; November 1615) was an English mathematician and cartographer noted for his book Certaine Errors in Navigation (1599; 2nd ed., 1610), which for the first time explained the mathematical basis of the Mercator projection, and set out a reference table giving the linear scale multiplication factor as a function of latitude, calculated for each minute of arc up to a latitude of 75°. This was in fact a table of values of the integral of the secant function, and was the essential step needed to make practical both the making and the navigational use of Mercator charts.*Wik At his Renaissance Mathematicus blog, Thony Christie points out that "Mercator printed and published a world map constructed according to this method (cylindrical) of projection in 1569 but he did not explain the mathematical rules on which it was based. He was a professional cartographer and globe maker and he probably hoped that if he kept his method secret then the people who wished to take advantage of this new development would have to order their maps and charts from him.... John Dee and Thomas Harriott both independently solved the mathematical problem of the projection but like Mercator neither of them made the knowledge public. We can however assume that both of them made use of this knowledge when teaching navigation and cartography, Dee to the pilots of the Muscovy Company and Harriot to Walter Raleigh’s sea captains.

The first person to publish the mathematical method of constructing such a chart was another English mathematicus Edward Wright in his book Certaine Errors in Navigation, first published in 1599."

**1850 Peter Scott Lang**(8 Oct 1850, 5 July 1926) graduated from Edinburgh University and after a period as assistant in Edinburgh he became Regius Professor of Mathematics at St Andrews. He held this position for 42 years. *SAU

**1873 Ejnar Hertzsprung**(8 Oct 1873; 21 Oct 1967) Danish astronomer who classified types of stars by relating their surface temperature (or colour) to their absolute brightness. A few years later Russell illustrated this relationship graphically in what is now known as the Hertzsprung-Russell diagram, which has become fundamental to the study of stellar evolution. In 1913 he established the luminosity scale of Cepheid variable stars.*TIS

**1908 Hans Arnold Heilbronn**(8 October 1908 – 28 April 1975) was a mathematicianb orn into a German-Jewish family. He was a student at the universities of Berlin, Freiburg and Göttingen, where he met Edmund Landau, who supervised his doctorate. In his thesis, he improved a result of Hoheisel on the size of prime gaps. *Wik

**1944 E. E. "Pat" Ballew**, Whose greatest contribution to mathematics was in helping to educate many great young people who went on to be successful in numerous walks of life. Editor/author of this blog.

**DEATHS**

**1647 Christian Longomontanus**(4 Oct 1562, 8 Oct 1647) Byname of Christian Severin, a Danish astronomer and astrologer who is best known for his association with, and published support for, Tycho Brahe. He became the first professor of astronomy at the University of Copenhagen, and in 1610 he received funds for instruments and he probably constructed a small observatory at his home. Longomontanus used Tycho's data to compile the Astronomia danica (1622), an exposition of the Tychonic system, which holds that the Sun revolves around the Earth and the other planets revolve around the Sun. He began the construction of the Copenhagen Observatory in 1632, but died before its completion.*TIS

**1652 John Greaves**(1602, 8 Oct 1652) Greaves was appointed as Professor of Geometry at Gresham College, London, in February 1631. He was able to retain his fellowship at Merton College, Oxford. His main scientific aim was the "practical and sober project of standardizing and synchronizing the weights and measures of all ancient and modern nations."

His desire to find out about measurements in the ancient world led him to plan visits to Italy and Egypt, where he wanted to make measurements of the pyramids. As Shalev puts it "It is metrology which fuelled Greaves's fascination with ancient monuments, and with the Great Pyramid above all."

In 1649 he published A Discourse of the Roman Foot, and Denarius; from whence, as from two Principles, the Measures and Weights used by the Ancients may be deduced. In the same year he published Elementa Linguae Persicae.*SAU

**1883 Professor Enoch Beery Seitz**, of Missouri State Normal School(

*now Truman State University*), was “stricken by that ‘demon of death.’ typhoid fever, and passed the mysterious shades, to be numbered with the silent majority.” “Prof. Seitz was in mathematics what Demosthenes was in oratory; Shakespeare in poetry; and Napoleon in war: the equal of the best, the peer of all the rest.” In case you have never heard him, see the biography in the ﬁrst volume (1894) of the Americal Mathematical Monthly, pp. 3–6. *VFR

A nice problem from Professor Seitz, Perhaps inspired by the Greenville hometown legend Annie Oakly and her rifleman ship, Seitz offered the problem:

"A cube is thrown into the air and a random shot fired through it; find the chance that the shot passes through the opposite side." From a nice biography of the professor *by John E. Zimmerman, Washington & Jefferson College

**1940 Robert Emden**(4 Mar 1862, 8 Oct 1940) Swiss astrophysicist and mathematician who wrote Gaskugeln (Gas Spheres, 1907), giving a mathematical model of stellar structure as the expansion and compression of gas spheres, wherein the forces of gravity and gas pressure are in equilibrium. He expanded on earlier work by J. H. Lane (1869) and A. Ritter (1878-83) who first derived equations describing stars as gaseous chemical, spherical bodies held together by their own gravity and obeying the known gas laws of thermodynamics. For four decades, the Lane-Emden equation was the foundation of theoretical work on the structure of stars: their central temperatures and pressures, masses, and equilibria. Emden also devised a hypothesis, no longer taken seriously, to explain sunspots. *TIS

**1973 Evan Tom Davies**(24 Sept 1904, 8 Oct 1973) graduated from the University of Wales at Aberystwyth and then studied in Rome and Paris. After lecturing at King's College London he was appointed to a professorship in Southampton. He worked in Differential Geometry and the Calculus of Variations. *SAU

**2005 Alfred William Goldie**(10 Dec 1920, 8 Oct 2005) was an English mathematician who proved an important result in Ring Theory. Goldie's first paper in this area Decompositions of semi-simple rings (1956) made an immediate impact since Jacobson included one of Goldie's theorems in his classic monograph Structure of Rings of 1956, acknowledging that it had been communicated by Goldie. Over the next few years Goldie's work on non-commutative Notherian rings would totally revolutionise the subject. He was able to prove totally unexpected structure theorems. Even his first steps towards these results were startling *SAU

Credits

*VFR = V Frederick Rickey, USMA

*TIS= Today in Science History

*Wik = Wikipedia

*SAU=St Andrews Univ. Math History

*CHM=Computer History Museum