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          Les éphémérides du 9 août      Cache   Translate Page   Web Page Cache   
Aujourd'hui 18e jour du signe astrologique du Lion. Selon le dicton, "Saint-Mathias casse la glace, mais s'il n'en trouve pas il faut bien qu'il en fasse".
Sont nés notamment ce jour: la romancière Pamela Lyndon Travers, l'astrophysicien William Fowler, le chef d'orchestre Ferenc Fricsay, le footballeur Mario Jorge Lobo Zagallo, la chanteuse Whitney Houston, le cosmonaute Roman Romanenko.

Journée internationale des populations autochtones.
Au Canada journée nationale des casques bleus e...

Podcast Journal Journal international diffusé en podcast et portail multimédia interactif de proximité:

          Grabbing women’s breasts not university policy      Cache   Translate Page   Web Page Cache   

Arizona State finds that Krauss did it.

An investigation by Arizona State University (ASU) in Tempe concluded this week that high-profile astrophysicist and atheist Lawrence Krauss violated the university’s sexual harassment policy by grabbing a woman’s breast at a conference in Australia in late 2016.

“Responsive action is being taken to prevent any further recurrence of similar conduct,” ASU’s executive vice president and provost, Mark Searle, wrote in a 31 July letter to Melanie Thomson, a microbiologist based in Ocean Grove, Australia, who is an outspoken advocate for women in science. Thomson, who witnessed the breast-grabbing incident, received the investigative reportfrom ASU’s Office of Equity and Inclusion (OEI) and shared it with Science.

In response to an

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          Red-hot voyage to sun will bring us closer to our star      Cache   Translate Page   Web Page Cache   
CAPE CANAVERAL, Fla. – A red-hot voyage to the sun is going to bring us closer to our star than ever before.

NASA's Parker Solar Probe will be the first spacecraft to "touch" the sun, hurtling through the sizzling solar atmosphere and coming within just 3.8 million miles of the surface.

It's designed to take solar punishment like never before, thanks to its revolutionary heat shield that's capable of withstanding 2,500 degrees Fahrenheit.

Liftoff is set for the pre-dawn hours of Saturday for this first-of-its-kind mission to a star.

"The coolest, hottest mission, baby, that's what it is," said Nicola Fox, the project scientist at Johns Hopkins University.

Roughly the size of a small car, Parker will get nearly seven times closer to the sun than previous spacecraft. To snuggle up to the sun, it will fly past Venus seven times over seven years. Each flyby will provide an orbit-shaping gravity boost, drawing it ever closer to the sun and straight into the corona – the sun's outermost atmosphere.

The closer, the better for figuring out why the corona is hundreds of times hotter than the sun's surface. Another mystery scientists hope to solve: What drives the solar wind? That's the steady, supersonic stream of charged particles blasting off the corona and into space in all directions.

"There are missions that are studying the solar wind, but we're going to get to the birthplace," Fox said.

Scientists expect the $1.5 billion mission to shed light not only on our own dynamic sun, but the billions of other yellow dwarf stars – and other types of stars – out there in the Milky Way and beyond. While granting us life, the sun also has the power to disrupt spacecraft in orbit, and communications and electronics on Earth.

"This is where we live," said NASA solar astrophysicist Alex Young. "We have to understand and characterize this place that we're traveling through."

The project was proposed in 1958 to a brand-new NASA, and "60 years later, and it's becoming a reality," said project manager Andy Driesman, also of Johns Hopkins, which designed and built the spacecraft. The technology for surviving such a close solar encounter, while still being light enough for flight, wasn't available until now.

Parker's 8-foot heat shield is just 4½ inches thick. Sandwiched between two carbon sheets is airy carbon foam. The front has a custom white ceramic coating to reflect sunlight; it's expected to glow cherry red when bombarded by the extreme solar heat.

Almost everything on the spacecraft will be behind this and thus in room-temperature shade while ducking through the jagged edges of the corona, without so much as a blister on its science instruments.

The spacecraft will hit 430,000 mph in the corona at closest approach. That's equivalent to going from Washington, D.C., to Philadelphia in a split second. Or Chicago to Beijing in under a minute.

This is the first NASA spacecraft to be named after someone still alive.

Eugene Parker, 91, professor emeritus at the University of Chicago, predicted the existence of solar wind 60 years ago. He plans be at Cape Canaveral for the launch. United Launch Alliance's Delta IV Heavy rocket is providing the muscle.

Parker got to inspect the spacecraft last fall. He said he's "holding my breath that everything goes well."

"This is a journey into never-never land, you might say, where it's too hot for any sensible spacecraft to function," Parker told Johns Hopkins' Fox in a recent interview. "But some very clever engineering and construction have succeeded in making what looks like a very workable instrument."

The spacecraft holds photos of Parker as well as a copy of his 1958 research paper on what he termed solar wind. Despite skepticism, NASA's Mariner 2 spacecraft proved Parker right in 1962.

Also on board: more than 1 million names of space fans submitted to NASA this past spring.

It's a fast-paced mission, with the first Venus encounter occurring less than two months after liftoff, in early October, and the first brush with the sun in November.

In all, the spacecraft will make 24 elongated laps around the sun, closer than the orbit of Mercury, the innermost planet. The records will start falling with the first orbit, when the Parker probe comes within 15.5 million miles (25 million kilometers) of the sun and beats the current record holder, NASA's former Helios 2 spacecraft. Helios 2 got within 27 million miles (43 million kilometers) of the sun in 1976.

Fox puts it this way: If the sun and Earth were on opposite ends of a football field, Mercury would be at the sun's 35-yard line, Helios 2 at the 29-yard line and the Parker probe at the 4-yard line.

NASA's Messenger, which orbited Mercury from 2011 to 2015, provided insight into the solar wind but was too away.

"You know something exciting is just around the bend, but where you're sitting you can't see what that is," Fox said. "So really the only way we can now do it is to do this daring mission to plunge into the corona."

The Parker probe's final three orbits – in 2024 and 2025 – will be the closest. The spacecraft eventually will run out of fuel and, no longer able to keep its heat shield pointed toward the sun, will burn and break apart – except perhaps for the rugged heat shield.

"It's a pretty tough shield," said Fox.


The Associated Press Health & Science Department receives support from the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content.

           NASA is sending a spaceship closer to the sun       Cache   Translate Page   Web Page Cache   
The Parker Solar Probe, named after American solar astrophysicist Eugene Parker will get within 3.9million miles of the sun’s surface and is set to blast off from Florida.
          Astrophysicist says aliens could be hiding behind repositioned stars      Cache   Translate Page   Web Page Cache   

Astrophysicist Dan Hooper thinks we’ll eventually have to wrangle the stars in our night sky, like wayward cattle straying from the herd, in order to keep the lights on. This is because the universe is constantly expanding and pulling stars with it. If he’s right, his logic would apply to all intelligent life in the universe — and could help us find aliens. Ask anyone who believes in extra-terrestrial intelligent life why, after thousands of years, we haven’t located aliens and they’ll tell you that we’re just not looking in the right places (or that we have, and the government…

This story continues at The Next Web
          8/9/2018: News: Nasa probe set to fly to the sun      Cache   Translate Page   Web Page Cache   
NASA will send a spacecraft on a mission to get a closer look at the sun. The Parker Solar Probe, named after American solar astrophysicist Eugene Parker, will fly closer to our star than any other man-made object. The car- sized probe, which will get...
          BURKE, BERNARD      Cache   Translate Page   Web Page Cache   
BURKE, Bernard Age 90, a 20-plus year resident of Cambridge and a professor emeritus of astrophysics at MIT, died peacefully on August 5. He was born...
          Astrophysicist says aliens could be hiding behind repositioned stars      Cache   Translate Page   Web Page Cache   

Astrophysicist Dan Hooper thinks we’ll eventually have to wrangle the stars in our night sky, like wayward cattle straying from the herd, in order to keep the lights on. This is because the universe is constantly expanding and pulling stars with it. If he’s right, his logic would apply to all intelligent life in the universe — and could help us find aliens. Ask anyone who believes in extra-terrestrial intelligent life why, after thousands of years, we haven’t located aliens and they’ll tell you that we’re just not looking in the right places (or that we have, and the government…

This story continues at The Next Web

          09/08/2018: NEWS: Nasa sets control for the heart of the sun      Cache   Translate Page   Web Page Cache   
NASA is set to launch a spacecraft on a scorching journey towards the sun, with an aim to offer the closest-ever glimpse of the star at the centre of the solar system. The Parker Solar Probe, named after American solar astrophysicist Eugene Parker,...
          Astrophysics for People in a Hurry      Cache   Translate Page   Web Page Cache   
Astrophysics for People in a Hurry
author: Neil deGrasse Tyson
name: Jake
average rating: 4.10
book published: 2017
rating: 0
read at:
date added: 2018/08/08
shelves: currently-reading, nonfiction, science

          Ученые обнаружили в диске вокруг новой планеты муравьиную кислоту      Cache   Translate Page   Web Page Cache   


Еще до образования твердых планет в протопланетных туманностях протекают активные процессы органического синтеза.

Сергей Парфенов из Уральского федерального университета совместно с коллегами из Германии, Италии, США и Франции впервые обнаружил органическую кислоту в протопланетном диске, причем в сравнительно высокой концентрации. Находка указывает на активное протекание процессов органического синтеза задолго до образования планет, а значит, в их первичном материале, сразу после возникновения данных небесных тел, уже должны присутствовать большие количества органических соединений. Новые результаты крайне важны для понимания того, в каких конкретно условиях протекает возникновение жизни на ранней стадии развития планетных систем. Соответствующая статья опубликована в The Astrophysical Journal Letters.

Исследователи использовали радиотелескоп ALMA (Чили) для наблюдений протопланетного диска молодого оранжевого карлика TW Гидра в 176 световых лет от нас. Возраст звезды около 10 миллионов лет, поэтому вокруг нее уже успел образоваться протопланетный диск и одна массивная (юпитероподобная) планета, но еще не сформировались планеты земного типа. Это дает весьма редкую возможность заглянуть в эпоху образования твердых землеподобных планет, как наша собственная, тем более что по массе и спектру оранжевые карлики относительно близки к желтым, к которым относится и наше Солнце.

Ученые проанализировали большой массив данных, полученных при наблюдении на частоте 129 мегагерц. При этом они получили спектр, соответствующий муравьиной кислоте.

Подробнее на Чердаке

          8/9/2018: NEWS: Nasa sets control for the heart of the sun      Cache   Translate Page   Web Page Cache   
NASA is set to launch a spacecraft on a scorching journey towards the sun, with an aim to offer the closest-ever glimpse of the star at the centre of the solar system. The Parker Solar Probe, named after American solar astrophysicist Eugene Parker,...
          流浪行星被发现能产生明亮的极光      Cache   Translate Page   Web Page Cache   
一颗巨大的流浪行星被发现能产生让地球极光相形见绌的明亮极光。根据发表在《The Astrophysical Journal》期刊上的一项研究,20 光年外的这颗流浪行星磁场强度 400 万倍于地磁场,质量  12.7 倍于木星。这颗没有恒星的行星编号为 SIMP J01365663+0933473,它产生如此强极光的原因未知。地球的上极光是来自太阳的带电粒子被地磁场吸引,与大气层中的粒子发生碰撞产生的发光现象。木星离太阳太遥远而不受太阳风的影响,它的带电粒子来自于它的卫星。研究人员怀疑,这颗流浪行星也有卫星。

          On This Day in Math - August 9      Cache   Translate Page   Web Page Cache   

You don't understand anything until you learn it more than one way.
— Marvin Minsky

The 221st day of the year; 221 the sum of consecutive prime numbers in two different ways 221 = (37 + 41 + 43 + 47 + 53) = (11 + 13 + 17 + 19 + 23 + 29 + 31 + 37 + 41)

221221 + 122 is prime, it is the only known number greater than one with this property.

221 is the number of 7-vertex Hamiltonian planar graphs ( a graph that allows a closed path that visits each node exactly once.)

0975 "The Sun was eclipsed . . . . Some people say that it was entirely total. During the hours mao and ch'en (some time between 5 and 9 h) it was all gone. It was the colour of ink and without light. All the birds flew about in confusion and the various stars were all visible. There was a general amnesty (on account of the eclipse)." From: Nihon Kiryaku. "At the hour ch'en (7-9 h), the Sun was eclipsed; it was completely total. All under heaven became entirely dark and the stars were all vis ible."
From: Fuso Ryakki. "The Sun was eclipsed; it was all gone. It was like ink and without light. The stars were all visible (or: stars were visible in the daytime)." From: Hyaku Rensho. These three Japanese quotations refer to a total solar eclipse of 9 August AD 975. Quoted in Historical Eclipses and Earth's Rotation, by F Richard Stephenson, Cambridge University Press, 1997, pages 267 and 268. *NSEC

1207 An educational institution is founded for the study of the works of Bhaskara II, an Indian mathematician and astronomer.*VFR
Bhaskara II was rightly achieved an outstanding reputation for his remarkable contribution. In 1207 an educational institution was set up to study Bhaskaracharya's ("Bhaskara the teacher")works. A medieval inscription in an Indian temple reads: Triumphant is the illustrious Bhaskaracharya whose feats are revered by both the wise and the learned. A poet endowed with fame and religious merit, he is like the crest on a peacock. It is from this quotation that the title of Joseph's book comes. *SAU

1654 Fermat to Carcavi "Monsieur, I was overjoyed to have had the same thoughts as those of M. Pascal, for I greatly admire his genius and I believe him to be capable of solving any problem he attempts. The friendship he offers is so dear to me and so precious that I shall not scruple to take advantage of it in publishing an edition of my Treatises. If it does not shock you, you could both help in bringing out this edition, and I suggest that you should be the editors: you could clarify or augment what seems too brief and thus relieve me of a care which my work prevents me from taking. I would like this volume to appear without my name even, leaving to you the choice of designation which would indicate the author, whom you could qualify simply as a friend." *York Univ Hist of Stats.

1658 Simon Douw obtains a patent for a pendulum clock that will draw Huygen’s attack in Horologium. “Today, no clock by Simon Douw is known; I find that most curious, it is as if he has been excised from history, deliberately. Dutch Court papers described Douw as "City clockmaker of Rotterdam... a master in the art of great tower, domestic or office clocks", ("en meester in de kunst van groote Toorn, Camer ofte Comptoirwerken"). Yet his mechanical insights. his escapement, also his drive mechanisms, are best, and now only, revealed by his Patent Grant on August 9th, 1658, and by the evidence and judgement in a claim and counterclaim started in the Provinces of Holland and West Friesland, but then referred to the Court of The Netherlands in October 1658, with a Judgement by Consent on December 5th, 1658. And that case went entirely in Douw's favour, against the highly favoured joint Complainants Huygens and Coster.
In itself, that is remarkable. Huygens, the Noble patrician, the most famous Dutch scientist, and the self-professed inventor of the pendulum clock, who had in the course of this trial published "Horologium", was forced by the judges to settle the case rather than face unfavourable verdict; also to concede Consent; also one-third Royalties to Douw. It would have been a crushing humiliation for Huygens, the seed of his libels. Subsequently, the Lower Court of Holland, Zeeland and Friesland confirmed to Douw, on December 16th and 19th 1658, their Upper Court's judgement by consent”. * From Keith Piggott

1895 Percival Lowell, convinced about intelligent beings on Mars, published an article in The Atlantic Monthly about how lucky they are to have low gravity. "LUCK OF THE BEING WHO LIVES ON MARS; He Can Do More Work Much More Easily than Man on Earth." *HT Paul Halpern‏ @phalpern

1898 Rudolf Diesel patents an internal combustion engine in the US (filed July 15, 1895.) "My invention has reference to improvements in apparatus for regulating the fuel supply in slow-combustion motors" *

1975 To display Mexican-Lebanese friendship, Mexico issued a stamp of the Teacher’s Monument in Mexico City by I. Naffa al Rozzi, which shows Cadmus, a mythical Phoenician, teaching the alphabet.


1537 Franciscus Barocius (9 August 1537 – 23 November 1604) born. In 1560 he published the first important translation of Proclus’ commentary on the first book of Euclid’s Elements. In 1587 he was brought before the Inquisition on charges of sorcery, more particularly of having caused a torrential rainstorm in Crete. *VFR

1602 Gilles de Roberval (August 9, 1602 – October 27, 1675)(His date of birth is given as 8th, 9th and 10th in various sources) was a French scientist who developed powerful methods in the early study of integration.*SAU Roberval was one of those mathematicians who, just before the invention of the infinitesimal calculus, occupied their attention with problems which are only soluble, or can be most easily solved, by some method involving limits or infinitesimals, which would today be solved by calculus. He worked on the quadrature of surfaces and the cubature of solids, which he accomplished, in some of the simpler cases, by an original method which he called the "Method of Indivisibles"; but he lost much of the credit of the discovery as he kept his method for his own use, while Bonaventura Cavalieri published a similar method which he independently invented.
Another of Roberval’s discoveries was a very general method of drawing tangents, by considering a curve as described by a moving point whose motion is the resultant of several simpler motions. (The limacon was named by Roberval in 1650 when he used it as an example of his methods of drawing tangents.)
He also discovered a method of deriving one curve from another, by means of which finite areas can be obtained equal to the areas between certain curves and their asymptotes. To these curves, which were also applied to effect some quadratures, Evangelista Torricelli gave the name "Robervallian lines."
(He also wrote a) work on the system of the universe, in which he supports the Copernican heliocentric system and attributes a mutual attraction to all particles of matter. *Wik
 I was recently informed (2018) by Vincent Panteloni that in France, the balance scale, "We refer to such a scale by saying 'une balance de Roberval'".

1757 Thomas Telford (9 August 1757 Glendinning, Westerkirk, Eskdale, Dumfriesshire, Scotland - 2 September 1834 (aged 77) 24 Abingdon Street, Westminster, London) He is the founder of modern bridge construction, his crowning achievement being the Menai suspension bridge in Wales. Do you know the shape of the cables on a suspension bridge? *VFR

1776 Count Amedeo Avogadro (9 August 1776, Turin, Piedmont – 9 July 1856) Italian chemist and physicist who found that at the same temperature and pressure equal volumes of all perfect gases contain the same number of particles, known as Avogadro's Law (1811) leading to the Avogadro's constant being 6.022 x 1023 units per mole of a substance. He realized the particules could be either atoms, or more often, combinations of atoms, for which he coined the word "molecule." This explained Gay-Lussac's law of combining volumes (1809). Further, Avogadro determined from the electrolysis of water that it contained molecules formed from two hydrogen atoms for each atom of oxygen, by which the individual oxygen atom was 16 times heavier than one hydrogen atom (not 8 times as suggested earlier by Dalton.) The Italian, Romano Amadeo Carlo Avogadro, had suggested [in 1811] that all gases have the same number of molecules in a given volume. Loschmidt figured out [in 1865] how many molecules that would be. John D. Cook suggested that maybe it should be called Loschmidt's constant, and pointed out three interesting coincidences involving Avogadro's Constant:
NA is approximately 24! (i.e., 24 factorial.)
The mass of the earth is approximately 10 NA kilograms.
The number of stars in the observable universe is 0.5 NA.
*John D. Cook, The Endeavour Blog

1819 Jonathan Homer Lane (August 9, 1819, Geneseo, New York – May 3, 1880, Washington D.C.) U.S. astrophysicist who was the first to investigate mathematically the Sun as a gaseous body. His work demonstrated the interrelationships of pressure, temperature, and density inside the Sun and was fundamental to the emergence of modern theories of stellar evolution.*TIS

1911 William Alfred "Willie" Fowler (August 9, 1911 – March 14, 1995)
American astrophysicist. He should not be confused with the British astronomer Alfred Fowler.
Fowler won the Henry Norris Russell Lectureship of the American Astronomical Society in 1963, the Eddington Medal in 1978, the Bruce Medal in 1979, and the Nobel Prize for Physics in 1983 for his theoretical and experimental studies of the nuclear reactions of importance in the formation of the chemical elements in the universe (shared with Subrahmanyan Chandrasekhar). *TIA

1919 Leona Woods (August 9, 1919 – November 10, 1986), later known as Leona Woods Marshall and Leona Woods Marshall Libby, was an American physicist who helped build the first nuclear reactor and the first atomic bomb.
At age 23, she was the youngest and only female member of the team which built and experimented with the world's first nuclear reactor (then called a pile ), Chicago Pile-1, in a project led by her mentor Enrico Fermi. In particular, Woods was instrumental in the construction and then utilization of geiger counters for analysis during experimentation. She was the only woman present when the reactor went critical. She worked with Fermi on the Manhattan Project, and, together with her first husband John Marshall, she subsequently helped solve the problem of xenon poisoning at the Hanford plutonium production site, and supervised the construction and operation of Hanford's plutonium production reactors.
After the war, she became a fellow at Fermi's Institute for Nuclear Studies. She later worked at the Institute for Advanced Studies in Princeton, New Jersey, the Brookhaven National Laboratory, and New York University, where she became a professor in 1962. Her research involved high-energy physics, astrophysics and cosmology. In 1966 she divorced Marshall and married Nobel laureate Willard Libby. She became a professor at the University of Colorado, and a staff member at RAND Corporation. In later life she became interested in ecological and environmental issues, and she devised a method of using the isotope ratios in tree rings to study climate change. She was a strong advocate of food irradiation as a means of killing harmful bacteria. *Wik

1927 Marvin Minsky (August 9, 1927 - January 24, 2016 (aged 88)) Biochemist and the founder of the MIT Artificial Intelligence Project. Marvin Minsky has made many contributions to AI, cognitive psychology, mathematics, computational linguistics, robotics, and optics. He holds several patents, including those for the first neural-network simulator (SNARC, 1951), the first head-mounted graphical display, the first confocal scanning microscope, and the LOGO "turtle" device. His other inventions include mechanical hands and the "Muse" synthesizer for musical variations (with E. Fredkin). In recent years he has worked chiefly on imparting to machines the human capacity for commonsense reasoning. *TIS He died in Boston of a cerebral hemorrhage .

1940 Linda Goldway Keen (8 August 1940- ) In addition to studying Riemann surfaces, Keen has worked in hyperbolic geometry, Kleinian groups and Fuchsian groups, complex analysis, and hyperbolic dynamics. In the field of hyperbolic geometry, she is known for the Collar lemma.
Keen has worked at the Institute for Advanced Study, Hunter College, University of California at Berkeley, Columbia University, Boston University, Princeton University, and the Massachusetts Institute of Technology, as well as at various mathematical institutes in Europe and South America. After her initial appointment in 1965, in 1974 Keen was promoted to Full Professor at Lehman College and the CUNY Graduate Center.
Keen served as president of the Association for Women in Mathematics during 1985-1986 and as vice-president of the American Mathematical Society during 1992-1995. She served on the Board of Trustees of the American Mathematical Society from 1999-2009 and as Associate Treasurer from 2009-2011. In 1975, she presented an AMS invited address and in 1989 she presented an MAA joint invited address. In 1993 she was selected as a Noether Lecturer. *Wik

1943 Jacques Lewiner, (9 August, 1943 - ) is a French physicist and inventor. He is Professor and Honorary Scientific Director of École supérieure de physique et de chimie industrielles de la ville de Paris (ESPCI ParisTech).
His works have been devoted to electrical insulators and particularly electrets, instrumentation and sensors, for instance in medical imaging, or on the improvement of telecommunication networks.
He has filed a large number of patent applications leading to industrial development, either through licenses granted to industrial companies or through start-up companies often created with former students or researchers. He has participated in the creation of various technology oriented start up companies, for instance Inventel, specializing in Telecommunications, Finsécur which develops and markets fire detection systems, Sculpteo which is an online 3D printing platform, Roowin in the field of chemical synthesis and Cynove in embedded electronics devices. Most of these companies have experienced a strong growth. For instance Inventel, which was the French leader for multimedia gateways was bought by Thomson SA in 2005.
Lewiner is laureate of the French Academy of Sciences in 1990, Knight in the National Order of the Legion of Honor, member of the French Academy of Technologies since 2005 and Honorary Fellow of the Technion. *Wik


1932 John Charles Fields died (May 14, 1863 - August 9, 1932). In his will he left funds for an international medal for contributions to mathematics. The International Congress of Mathematicians in Zurich in 1932 adopted the proposal, and the first Fields Medals were awarded at the Oslo Congress in 1936 to Lars Ahlfors, age 29 of Harvard, and Jesse Douglas, age 39 of Massachusetts Institute of Technology. *VFR It became the most prestigious award for mathematicians, often referred to as the equivalent of a Nobel Prize for mathematicians. As a professor at the University of Toronto, he had worked to bring the International Congress of Mathematicians to Toronto (1924). The Congress was so successful that afterward there was a surplus of about\( $2,500\) which Fields, as chairman of the organizing committee, proposed be used to fund two medals to be awarded at each of future Congresses. This was approved on 24 Feb 1931. He died the following year, leaving \($47,000\) as additional funding for the medals, which have been awarded since 1936.*TIS

1969 Cecil Frank Powell (5 December 1903 – 9 August 1969) British physicist and winner of the Nobel Prize for Physics in 1950 for his development of the photographic method of studying nuclear processes and for the resulting discovery of the pion (pi-meson), a heavy subatomic particle. The pion proved to be the hypothetical particle proposed in 1935 by Yukawa Hideki of Japan in his theory.*TIS

1994 Helena Rasiowa (June 20, 1917 – August 9, 1994) worked in algebraic logic and the mathematical foundations of computer science.*SAU

2006 James Alfred Van Allen (September 7, 1914 – August 9, 2006) American physicist who discovered the Earth's magnetosphere, two toroidal zones of radiation due to trapped charged particles encircling the Earth (also known as the Van Allen radiation belts). During WWII he gained experience miniaturizing electronics, such as in the proximity fuse of a missile. After the war, he studied cosmic radiation, taking advantage of the unused German stock of V2 rockets launched into the outer regions of the atmosphere, carrying research devices using radio to relay back the data gathered. He was also involved in the early U.S. space program, and he had radiation measuring instruments on the first U.S. satellite, Explorer 1, launched 31 Jan 1958 with follow-up carried out by satellites Explorer 3 and 4 later the same year.*TIS

2007 Graham Robert Allan (August 13, 1936 Southgate, London - August 9, 2007 (aged 70)) was an English mathematician, specializing in Banach algebras. He was a reader in functional analysis and vice-master of Churchill College at Cambridge University. *Wik

*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
          Pourquoi n’avons-nous pas encore trouvé d’aliens ? Pour cet astrophysicien, nous ne regardons pas au bon endroit      Cache   Translate Page   Web Page Cache   

L'astrophysicien Dan Hooper pense savoir où nous devrions chercher les extraterrestres. Selon sa théorie, ils lutteraient contre l'expansion de l'univers en créant des structures pour récupérer l'énergie des étoiles. Nous devrions chercher des traces de ce passage. [Lire la suite]
          Macaulay Culkin Shades The Big Bang Theory in Explaining Why He Turned Down Show Three Times      Cache   Translate Page   Web Page Cache   

Macaulay Culkin was almost one of TV's biggest stars. Culkin revealed in a new interview that he was approached to star in The Big Bang Theory but turned it down - three times. The Home Alone actor, 37, appeared on the Joe Rogan Experience podcast where he admitted to passing on the CBS hit, though he doesn't specify which role. "They pursued me for The Big Bang Theory," Culkin said. "And I said no. It was kind of like, the way the pitch was, ‘Alright, these two astrophysicist nerds and a pretty girl lives with them. Yoinks!' That was the pitch. And I was like, ‘Yeah, . . .
          NASA is going closer to the Sun than anyone has gone before      Cache   Translate Page   Web Page Cache   
By Don Lincoln In a story from Greek mythology, a clever craftsman named Daedalus was imprisoned in a tower for knowing too much. To escape, he fashioned a set of wings made of feathers and wax, one for him and one for his son Icarus. As they made their escape, he cautioned the boy to not fly too high, as his wings would melt. Icarus ignored his father, soared too close to the Sun, and fell to his death. Luckily for astronomers and science enthusiasts everywhere, NASA has completely ignored this cautionary tale. Sometime in the two weeks starting Saturday, NASA will launch the Parker Solar Probe, a spacecraft that will fly closer to the Sun than any previous space mission. Its objective is to pass through the Sun’s corona and study the complicated magnetic fields that surround it. The probe was named after legendary American astrophysicist Eugene Parker who, in the 1950s, contributed significantly to our understanding of the environment in space surrounding the Sun. You might think that the Sun is well understood, given that we’ve been aware of it for millennia, but it is a coquettish beast, with some significant mysteries. The sun is a nuclear furnace, constantly shooting hot plasma — mostly protons and electrons from overheated hydrogen atoms — off into space. That hot plasma is the origin of the beautiful aurorae — known in the Northern hemisphere as the Northern lights — seen in the frigid nights of the polar regions. Continue reading by clicking the name of the source below.
          NASA is sending a spaceship closer to the sun than anyone has ever gone before where it will endure 2,510F heat      Cache   Translate Page   Web Page Cache   
Daily Mail (UK), by Staff Posted By: JoniTx- Thu, 09 12 2018 03:12:12 GMT NASA will send a spacecraft on a mission to get a closer look at the sun. The Parker Solar Probe, named after American solar astrophysicist Eugene Parker, will fly closer to our star than any other man'made object. The car'sized probe, which will get within 3.9million miles of the sun’s surface, is set to blast off from Cape Canaveral, Florida, on Saturday at 8.33am British time. It is expected to approach the sun in 2024. (Photo) Scientists hope to unlock mysteries such as why the sun’s corona, the outermost layer of its atmosphere, is hotter than its surface. The spacecraft
          2nd Workshop on Science with the New Generation of High Energy Gamma-ray Experiments : between Astrophysics and Astroparticle Physics      Cache   Translate Page   Web Page Cache   
          The Future of Space Travel      Cache   Translate Page   Web Page Cache   
American astronauts haven’t been sent into orbit in almost a decade. NASA halted its space shuttle program in 2011 because it was too expensive. But that’s going to change next year. The space agency announced last week that four flights will take astronauts to the International Space Station in 2019. The team, called the Commercial Crew Nine, will also be the first people to fly on private spacecrafts. Join us today for a discussion about what the future holds for space colonization, tourism and the Trump Administration’s Space Force. Guests: Tariq Malik , managing editor, Fraser Cain, publisher of Universe Today Joe Pappalardo , author of “Spaceport Earth” and contributing editor at Popular Mechanics Paul Sutter , astrophysicist at Ohio State University and chief scientist at COSI Science Center
          ASU astrophysicist helps discover that ultrahot planets have starlike atmospheres      Cache   Translate Page   Web Page Cache   
An unusual kind of star-planet hybrid atmosphere is emerging from studies of ultrahot planets orbiting close to other stars.
          NASA is flying a $1.5 billion spacecraft into the sun — here's why      Cache   Translate Page   Web Page Cache   

NASA will soon launch its Parker Solar Probe on a mission that will take it closer to the sun than any spacecraft in history. The probe will fly straight into the sun's outer atmosphere, called the corona, where violent storms erupt that could destroy our tech-driven way of life. If we want to avoid living like people did back in the Stone Age, we'll need Parker Solar Probe's data. Following is a transcript of the video.

NASA is about to go where no one has gone before. The Sun. That’s right. NASA is flying a 1.5 billion-dollar spacecraft into the hottest, most violent object in our solar system. All in the name of science.

NASA’s unmanned Parker Solar Probe will come to within 3.83 million miles of the solar surface. Now, that might not sound very close but it’s about SEVEN TIMES closer than any spacecraft has gone before. And puts the probe smack inside one of the sun’s most treacherous layers:  The corona. The outermost layer of the Sun.

Here, the temperatures fluctuate from 1 to 5 million degrees FahrenheitAnd solar flares exist that are so big they could swallow our planet whole. So, why are we going here, again? It turns out, the sun poses a major threat to our modern way of life. Powerful magnetic fields form near the sun’s surface. Where they sometimes spark violent eruptions called coronal mass ejections.

These ejections fire a surge of highly-charged particles into space that will fry any electronic circuits on impact. That includes circuits inside our satellites that control cell service, the internet, GPS, the stock exchange, and much more.

In 2014, for example, astrophysicist Daniel N. Baker explained what may happen if one of these powerful storms hit Earth directly, explaining that it could:

“cause widespread power blackouts, disabling everything that plugs into a wall socket. Most people wouldn’t even be able to flush their toilet because urban water supplies largely rely on electric pumps.”

Such a strike could cost an estimated $2 trillion in damage — 10 times more than Hurricane Katrina. Now luckily, space is a big place, which makes Earth a relatively small and tricky target. In fact, the last time a powerful storm like this struck our planet was more than 150 years ago, back in 1859. But the risk is there. And NASA predicts there’s a 12% chance we’ll get hit within the next decade.

That’s where Parker Solar Probe comes in. The probe can’t prevent an ejection from happening. But it can study the corona so that we may better understand the warning signs of an impending storm. And with enough notice, we may be able to protect our satellites from harm.

In addition to spying on the sun, Parker Solar Probe has another very important job: Don’t. Melt.

To that end, NASA has prepped the probe with four highly-tuned sensors and an impressive heat shield that will protect the probe’s instruments. The sensors are there to make sure the shield stays directed at the sun at all times. The mission will involve not one, or two, but 24 dives into the sun. Which are scheduled to take place up through the year 2025.

Join the conversation about this story »

          Nasa probe will still be circling Sun at end of Solar System say scientists      Cache   Translate Page   Web Page Cache   

Nasa probe will still be circling Sun at end of Solar System say scientistsNasa's new solar spacecraft is so indestructable that parts of it will be circling the Sun until the Solar System ends, eight billion years from now, scientists have said.  The US space agency launches its Parker Solar Probe on Saturday, which will travel closer to the Sun than any mission before, to unlock the secrets of fierce radioactive storms which threaten Earth.  Earth, and all the other objects in the Solar System are constantly plowing through what is known as the solar wind - a constant stream of high-energy particles, mostly protons and electrons, hurled into space by The Sun. These radioactive storms are so powerful they are able to knock out satellites, disrupt services such as communications and GPS, threaten aircraft and in even interfere with electricity supplies. The mission Sun’s outer atmosphere, or corona, the closest any man-made instrument has ever got to a star.  For seven years it will orbit at around 3.38 million miles from the star's surface, where temperatures reach 1,400C. The probe is relying on a 4.5 inch carbon heat shield which has taken 10 years to develop and which is so strong it will survive for billions of years even when the rest of the spacecraft has disintegrated. Speaking at a briefing ahead of the launch, Andy Driesman, Parker Solar Probe Programme Manager from Johns Hopkins University said: "At four million miles the Sun is very hot, so we need to bring an umbrella with us. "It’s a carbon heat shield. It took 18 months to fabricate it and a decade to develop it.  "Eventually the spacecraft will run out of propellant and will leave altitude control and parts of it will transition into the Sun. But hopefully in 10 to 20 years there is going to be this carbon disc and that will be around to the end of the Solar System." The Parker Solar Probe  Credit: Ed Whitman Johns Hopkins APL/NASA The spacecraft also holds a memory card containing the names of more than 1.1 million members of the public who were asked to write in to support the mission. London-born professor Nicky Fox, project scientist from Johns Hopkins University, said: "I think the spacecraft will break up into parts and form dust, and then those names will orbit the Sun forever." The nearest a spacecraft has previously come to the Sun was the Helios 2 mission in 1976, which flew to within 27 million miles. Once inside the corona, sensory equipment will attempt to ‘taste’ and ‘smell’ electronic particles while they are still moving slowly enough to be measured. Professor Mathew Owens, space scientist at the University of Reading, said: “It's an incredibly hostile environment in which to do science, so the spacecraft has faced enormous engineering challenges. But everything is looking positive for Saturday. “The thing we really don't understand about the Sun, and therefore stars in general, is why its atmosphere gets hotter further away from the heat source. “We've been trying to solve this mystery for more than 50 years, by taking measurements from a nice, safe distance, and it's left us in an unusual position. We've got a bunch of theories that seem to work, but don't know which ones actually explain the Sun.” Currently, solar activity is monitored by a network of satellites, but scientists still have a poo understanding of how radiation builds up in the star’s outer atmosphere and then accelerates towards Earth. A better understanding of “space weather” is also considered crucial for protecting astronauts and their equipment for any future endeavours to colonise the Moon or Mars. The Parker Solar Probe will go closer to a star than any mission has ever gone  Credit: Nasa The Parker Solar Probe, which weights 1,400lbs, will travel faster than any craft ever before at 430,000 mph, and during its a seven-year mission will make 24 orbits of the Sun. The spacecraft will carry instruments to measure bulk plasma, described as the 'bread and butter' of solar waves, as well as a full package of magnetic measuring equipment. Eugene Parker, who the mission is named after  Credit: AFP It will also carry a white light imager, dubbed 'Whisper' which can photograph solar waves. “Where does the solar wind come from? What causes flares and coronal mass ejections? We still don’t understand these processes,” said Justin Kasper, professor of climate and space sciences and engineering at the University of Michigan, mission principal investigator on the Parker Solar Probe. “The Parker Solar Probe will help us do a much better job of predicting when a disturbance in the solar wind could hit Earth.” The mission was named after Eugene Parker, the solar astrophysicist who first discovered the solar wind, and has been in the works for more than half a century. The memory card on board also contains a copy of his first scientific paper outlining his work. It was conceived before a space program, or even Nasa, existed.

          Finding the Happy Medium of Black Holes      Cache   Translate Page   Web Page Cache   
Credit: X-ray: NASA/CXC/ICE/M.Mezcua et al.;
Infrared: NASA/JPL-Caltech; Illustration: NASA/CXC/A.Hobart

This image shows data from a massive observing campaign that includes NASA's Chandra X-ray Observatory. These Chandra data have provided strong evidence for the existence of so-called intermediate-mass black holes (IMBHs). Combined with a separate study also using Chandra data, these results may allow astronomers to better understand how the very largest black holes in the early Universe formed, as described in our latest press release.

The COSMOS ("cosmic evolution survey") Legacy Survey has assembled data from some of the world's most powerful telescopes spanning the electromagnetic spectrum. This image contains Chandra data from this survey, equivalent to about 4.6 million seconds of observing time. The colors in this image represent different levels of X-ray energy detected by Chandra. Here the lowest-energy X-rays are red, the medium band is green, and the highest-energy X-rays observed by Chandra are blue. Most of the colored dots in this image are black holes. Data from the Spitzer Space Telescope are shown in grey. The inset shows an artist's impression of a growing black hole in the center of a galaxy. A disk of material surrounding the black hole and a jet of outflowing material are also depicted.

Two new separate studies using the Chandra COSMOS-Legacy survey data and other Chandra data have independently collected samples of IMBHs, an elusive category of black holes in between stellar mass black holes and the supermassive black holes found in the central regions of massive galaxies.

One team of researchers identified 40 growing black holes in dwarf galaxies. Twelve of them are located at distances more than five billion light years from Earth and the most distant is 10.9 billion light years away, the most distant growing black hole in a dwarf galaxy ever seen. Most of these sources are likely IMBHs with masses that are about 10,000 to 100,000 times that of the Sun.

A second team found a separate, important sample of possible IMBHs in galaxies that are closer to Earth. In this sample, the most distant IMBH candidate is about 2.8 billion light years from Earth and about 90% of the IMBH candidates they discovered are no more than 1.3 billion light years away.

They detected 305 galaxies in their survey with black hole masses less than 300,000 solar masses. Observations with Chandra and with ESA's XMM-Newton of a small part of this sample show that about half of the 305 IMBH candidates are likely to be valid IMBHs. The masses for the ten sources detected with X-ray observations were determined to be between 40,000 and 300,000 times the mass of the Sun.

IMBHs may be able to explain how the very biggest black holes, the supermassive ones, were able to form so quickly after the Big Bang. One leading explanation is that supermassive black holes grow over time from smaller black holes "seeds" containing about a hundred times the Sun's mass. Some of these seeds should merge to form IMBHs. Another explanation is that they form very quickly from the collapse of a giant cloud of gas with a mass equal to hundreds of thousands of times that of the Sun. There is yet to be a consensus among astronomers on the role IMBHs may play.

A paper describing the COSMOS-Legacy result by Mar Mezcua (Institute for Space Sciences, Spain) and colleagues was published in the August issue of the Monthly Notices of the Royal Astronomical Society and is available online. The paper by Igor Chilingarian (Harvard-Smithsonian Center for Astrophysics) on the closer IMBH sample is being published in the August 10th issue of The Astrophysical Journal and is available online.

NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

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