Chandrasekhar--- photos

Farewell to a newly married Chandra with wife Lalitha
at the Madras railway station (1936)

Planetary Nebula

TOTAL LUNAR ECLIPSE

LUNAR HALO

In the image you can also see Mars (below the moon, out of the halo) and the star Capella (left, inside the halo).

Made by NASA's Chandra Xray Observatory

Chandra X ray Observatory

Asteroid

S Chandrasekhar

S Chandrasekhar ... By Sulekha Rani.R, P.G.T Chemistry ,K V NTPC Kayamkulam

Early life and education

Chandrasekhar was the third of ten children born to Sita Ayyar (née Balakrishnan) and Chandrasekhara Subrahmanya Ayyar (C.S. Ayyar), a senior officer in the Indian Audits and Accounts Department in the railway sevices, who was posted in Lahore as the Deputy Auditor General of the Northwestern Railways. Chandrasekhar's mother was devoted to intellectual pursuits and had translated Henrik Ibsen's A Doll House into Tamil. His father was an accomplished Carnatic music violinist who had authored several books on musicology. Chandrasekhar, also known as Chandra, was the nephew of Nobel-prize winning physicist C. V. Raman.
Chandra had two elder sisters, Rajalakshmi and Balaparvathi. Being the first son in the family, Chandra’s birth rejoiced his parents, for only the son preserves the family lineage, and to whom all family belongings are bequeathed. The eldest son traditionally assumes his father’s responsibilities once a grown man, and performs certain annual rituals. Following Chandra, his younger siblings included three brothers—Vishwanathan, Balakrishnan, and Ramanathan—and four sisters—Sarada, Vidya, Savitri, and Sundari. Chandrasekhar, a common Tamil name, is one of the appellations of the Hindu deity Shiva and means "holder of the moon" in Sanskrit.
At the age of six, Chandra’s family moved from Lahore to Lucknow, Uttar Pradesh, in northern India. A couple years later, C.S. Ayyar became Deputy Accountant-General in Madras, which involved a lot of travel as he was often transferred from place to place. Therefore, he settled his family at a home where they could stay while he traveled.
On Chandra’s memories of his childhood, Kameshwar C. Wali stated in Chandra: A Biography of S. Chandrasekhar, “The Ayyars’ house in Lahore was outside the city walls, not far from a large public garden known as the Lawrence Gardens. Chandra has few memories of his childhood, but he does remember frequent visits to the gardens and the Anarkali bazaar, which is even now a well-known and popular shopping place in Lahore, teeming with products from all over the world. He also distinctly remembers the beginning of the First World War in 1914, which coincided with the birth of his younger brother Balakrishnan.”
Chandrasekhar’s elder sisters remember him as a very naughty, mischievous younger brother. Wali states, “A healthy and handsome child… Chandra used to pick on his oldest sister, Rajalakshmi, by teasing her and quarreling with her over toys. “He used to take the lion’s share of everything,” recalls his sister Bala. “He would break his things first and take my elder sister’s.”
Chandra’s schooling was taken care of by his parents at his home; he officially started at the age of five, on the auspicious day of Vijayadasami. Chandra remembers, “My father used to teach me in the mornings before he went to his office, and then after he went to the office, my mother would teach me Tamil.” C.S. Ayyar hoped for Chandra to become an Indian Civil Service (ICS) officer, an esteemed position. On this subject Wali stated, “ He enjoyed learning English, and arithmetic caught his fancy very early. 'I remember very well,' he says, 'that my father used to assign lessons and exercises. I used to do far more and very often went far ahead of the assignments. I found that I could study the books on arithmetic on my own. So when my father came home, I had done one chapter (or more) ahead of what he wanted.' At first, Chandra’s father was amazed, but he and others soon realized that they had an exceptionally bright child in their midst.”
Another individual in the earlier generation of his family, his uncle Sir C.V. Raman, had exhibited brilliance himself, and even won the Nobel Prize. With this example set, Chandra was allowed to choose his own route in life; unlike Sir C.V. Raman, Chandra did not face much opposition from his family in his going away from civil service in India.
It was not until 1921, when Chandra was eleven years old, that he attended regular school. He was readily accepted into Hindu High School and skipped two years of normal high school.
Chandrasekhar attended the Hindu High School, Triplicane, Madras, British India until 1925. His first year passed by disappointingly. Having been used to taking subjects he liked (mainly English and arithmetic) at home, he did not like the requirement to also study history, geography, and general science, along with periodic examinations. The following year, Chandra was more excited, as his curriculum included algebra and geometry. Wali stated, “Without waiting for classes to begin, he began studying these subjects during summer vacation. 'I remember getting the books of my higher class,' says Chandra, 'and reading them ahead of classes. I remember reading Piorpoint’s texts on geometry; I went right through the first two books before I got into my fourth form. When I got to the fourth form, I knew all the geometry and all the algebra they were going to teach, and in fact more—permutations and combinations, solving cubic equations, and so on. Similarly in my [next three] summer vacations, I started studying conic sections, coordinate geometry, calculus, and differential equations.'”
With such great motivation, Chandra did extremely well in high school. When only fifteen, he started his studies at Presidency College until 1930, obtaining his bachelor's degree, B.Sc. (Hon.), in physics in June 1930. The principal of Presidency College, Principal Fyson, called Chandra into his office one day. Principal Fyson told Chandra that he was going to be offered a Government of India scholarship to pursue his research in England. This scholarship was created just for Chandra, and was not open for any other applicants. Chandra met with M.A. Candeth (Deputy Director of Public Instruction) and Earlam Smith (former professor of chemistry who became Director of Public Instruction) on February 12, 1930, and on the 15th, he attended an interview with Mr. Subbaroyan, Education Minister of the Madras State Government. The scholarship would be granted to him provided that Chandra agreed to serve either in the Madras state service or at the Presidency College after his return. Also, it would be awarded to him if he completed his honors course and secured the first-class grade. These stipulations were not a problem for Chandra.
During the next few months, Chandra put in all his energy to studying for the final examinations. As predicted, he secured first rank, and his grades set a new record. On May 22, 1930, Chandrasekhar was awarded the Government of India scholarship to pursue graduate studies at the University of Cambridge, where he became a research student of Professor R.H. Fowler and was admitted to Trinity College, Cambridge. On the advice of Prof. P. A. M. Dirac, Chandrasekhar spent a year at the Institut for Teoretisk Fysik in Copenhagen, where he met Prof. Niels Bohr.
In the summer of 1933, Chandrasekhar was awarded his Ph.D. degree at Cambridge. However, he faced a dilemma: in order to keep his scholarship, he must return to India and take up a position as he promised. Even his father was urging his return to India, since he had been away for three years already. Chandra, on the other hand, wanted to remain in England to continue his research. In the meantime, he applied for Fellowship at Trinity College. Professor Fowler told him of the great competition for the Fellowship, and didn’t think Chandra would be able to get in. Chandra himself greatly doubted his chances, but took the required examinations anyway. But to Chandra’s surprise, the following October, he was elected to a Prize Fellowship at Trinity College for the period 1933-37. He attempted to mollify his father, stating that by being a Fellow, his settlement in India would be much easier, as he would get much more respect from the government, and thus be able to secure a position of his liking upon his return. During his Fellowship at Trinity College, Chandra formed friendships with Sir Arthur Eddington and Professor E. A. Milne.
In September 1936, Chandrasekhar married Lalitha Doraiswamy, who he had met as a fellow student at Presidency College, Madras, and who was a year junior to him. In his Nobel autobiography, Chandrasekhar wrote, "Lalitha's patient understanding, support, and encouragement have been the central facts of my life."
Career

In the year 1935, another opportunity to settle with a solid job in India accosted Chandra. He planned to apply, but canceled his plan after hearing that his good friend S. Chowla (another Indian student he met during his first visit to Cambridge) was also a candidate. Chandra, who admired his work and personality, found it unfair to apply to a position that he may not even be able to take on time, with his other commitment to lecture in America. This disappointed his father into thinking Chandra’s chances of coming back to India had diminished greatly. However, Chandra later found that because of his uncle C.V. Raman’s influence, another scientist, Nagendra Nath, was competing against Chowla for the position that Chowla wanted so badly. In face of this event, Chandra wrote to his father, “I am so disgusted with the whole situation that my desire to settle finally in India and be of some service to Indian science seems to dwindle day by day.”
In January 1937, Chandrasekhar was recruited to the University of Chicago faculty as Assistant Professor by Dr. Otto Struve and President Robert Maynard Hutchins. Here he stayed at Williams Bay, Wisconsin, and Chandra set off on his scientific career at the Yerkes Observatory of the University of Chicago. He was to remain at the university for his entire career, becoming Morton D. Hull Distinguished Service Professor of Theoretical Astrophysics in 1952 and became a naturalized citizen of the United States in 1953. He attained emeritus status at the university in 1985.
During World War II, Chandrasekhar worked at the Ballistic Research Laboratories at the Aberdeen Proving Ground in Maryland. While there, he worked on problems of ballistics; for example, two reports from 1943 were titled, On the decay of plane shock waves and The normal reflection of a blast wave.[3]
Chandrasekhar worked continuously in one specific area of astrophysics for a number of years, then moved to another area. Consequently, his working life can be divided into distinct periods. He studied stellar structure, including the theory of white dwarfs, during the years 1929 to 1939, and subsequently focused on stellar dynamics from 1939 to 1943. Next, he concentrated on the theory of radiative transfer and the quantum theory of the negative ion of hydrogen from 1943 to 1950. This was followed by sustained work on hydrodynamic and hydromagnetic stability from 1950 to 1961. In the 1960s, he studied the equilibrium and the stability of ellipsoidal figures of equilibrium, but also general relativity. During the period, 1971 to 1983 he studied the mathematical theory of black holes, and, finally, during the late 1980s, he worked on the theory of colliding gravitational waves.
During the years 1990 to 1995, Chandrasekhar worked on a project which was devoted to explaining the detailed geometric arguments in Sir Isaac Newton's Philosophiae Naturalis Principia Mathematica using the language and methods of ordinary calculus. The effort resulted in the book Newton's Principia for the Common Reader, published in 1995.
Chandrasekhar died of heart failure in Chicago in 1995, and was survived by his wife, Lalitha Chandrasekhar. In the Biographical Memoirs of the Fellows of the Royal Society of London, R. J. Tayler wrote: "Chandrasekhar was a classical applied mathematician whose research was primarily applied in astronomy and whose like will probably never be seen again."
Nobel prize

He was awarded the Nobel Prize in Physics in 1983 for his studies on the physical processes important to the structure and evolution of stars. He was, however, upset that the citation mentioned only his earliest work, seeing this as a denigration of a lifetime of achievements. It is not certain if the Nobel selection committee was at least remotely influenced in formulating this citation by the early criticisms of Sir Arthur Stanley Eddington, another distinguished astrophysicist of his time and a senior to him. His life's achievement may be glimpsed in the footnotes to his Nobel lecture.
Legacy

Chandrasekhar's most famous success was the astrophysical Chandrasekhar limit. The limit describes the maximum mass (~1.44 solar masses) of a white dwarf star, or equivalently, the minimum mass for which a star will ultimately collapse into a neutron star or black hole (following a supernova). The limit was first calculated by Chandrasekhar while on a ship from India to Cambridge, England, where he was to study under the eminent astrophysicist, Sir Ralph Howard Fowler. When Chandrasekhar first proposed his ideas, he was opposed by the British physicist Arthur Eddington, and this may have played a part in his decision to move to the University of Chicago in the United States.
Honors

Awards
Fellow of the Royal Society (1944)
Henry Norris Russell Lectureship (1949)
Bruce Medal (1952)
Gold Medal of the Royal Astronomical Society (1953)
National Medal of Science award by President Lyndon Johnson (1967)
Henry Draper Medal (1971)
Nobel Prize in Physics (1983)
Copley Medal, the highest honor of the Royal Society (1984)
Named after him
In 1999, NASA named the third of its four "Great Observatories'" after Chandrasekhar. This followed a naming contest which attracted 6,000 entries from fifty states and sixty-one countries. The Chandra X-ray Observatory was launched and deployed by Space Shuttle Columbia on July 23, 1999.
The Chandrasekhar number, an important dimensionless number of magnetohydrodynamics, is named after him.
The asteroid 1958 Chandra is also named after Chandrasekhar.

Superconductors go fractal.

Oxygen atoms arrange themselves in a self-similar pattern

Sulekha Rani.R , P.G.T Chemistry,

KV NTPC Kayamkulam

A new experiment using powerful X-ray beams has found a surprising pattern lurking in a superconductor, a material that conducts electricity without energy-sapping resistance. In a particular kind of superconductor, oxygen atoms are physically arranged as a fractal, showing the same pattern at small and large scales.

Fractals have been spotted in places as diverse as broccoli, England’s coastline and financial markets. Here, the fractal pattern boosts the efficiency of the superconductor, scientists report August 12 in Nature.

The new study is “experimental physics at its best,” says physicist Jan Zaanen of Leiden University in the Netherlands, who wrote an accompanying article in the journal. “A new machine comes on line, and it produces a surprise nobody expects.”

Though the researchers don’t yet know how the pattern forms or why it enhances superconductivity, they hope the discovery will help in the quest to develop superconductors that work at room temperature, says study coauthor Antonio Bianconi of Sapienza University of Rome. Physicists have been pushing to make superconductivity happen at higher temperatures, but the top performers are still stuck about halfway between absolute zero and room temperature.

Looking at a copper-oxide superconductor that can perform at approximately -233 degrees Celsius, Bianconi and his team developed a new technique to determine the detailed structure of its atoms. They bombarded the superconductor with powerful X-rays generated at the European Synchrotron Radiation Facility in Grenoble, France. The resulting diffraction pattern revealed atoms’ locations.

The team knew the material was made like a layered cake, with layers of superconducting copper oxide alternating with spacer layers. At higher temperatures, oxygen atoms tend to roam around in the spacer layer. But when temperatures drop, they settle down. These oxygen atoms — and the electrons they bring to what would otherwise be vacancies — are thought to contribute to the drop in resistance that accompanies superconductivity. But until now, no one had been able to see the structure with high resolution.

Bianconi and his team got a shock when they realized the pattern formed by the once-roaming oxygen atoms was fractal. The pattern looked the same at the 1-micrometer scale as it did at the 400-micrometer scale.

This self-similarity was completely unexpected in superconductors, Bianconi says. “We were very astonished. We couldn’t believe our eyes,” he says. “This is not an area where we expected to see a fractal pattern.”

To see whether the fractal pattern was important, the team interfered with it by heating and then quickly cooling the superconductor. Crystals with stronger fractal patterns performed better as a superconductor at higher temperatures than those with weaker fractal patterns. The fractal pattern enhanced the superconductor’s performance, the team concluded.

The finding is “very interesting, since it provides a much-welcomed fresh view of the high temperature superconductivity problem,” comments physicist Elbio Dagotto of the University of Tennessee in Knoxville and the Oak Ridge National Laboratory.

Figuring out why the fractal pattern forms in these copper-oxide crystals and how it influences the superconductivity are the next big questions, Bianconi says. Once the details are uncovered, researchers could control the arrangement of oxygen atoms to design better copper-oxide superconductors — perhaps even those that operate at room temperature.

SuperHeavy element 117

Superheavy element 117.

Sulekha Rani.R, P.G.T Chemistry

KV NTPC Kayamkulam

Physicists have reported synthesizing element 117, the latest achievement in their quest to create “superheavy” elements in the laboratory. A paper describing the discovery has been accepted for publication in Physical Review Letters.

A team led by Yuri Oganessian of the Joint Institute for Nuclear Research in Dubna, Russia, reports smashing together calcium-48 — an isotope with 20 protons and 28 neutrons — and berkelium-249, which has 97 protons and 152 neutrons. The collisions spit out either three or four neutrons, creating two different isotopes of an element with 117 protons.

Sigurd Hofmann, a nuclear physicist at the GSI research center in Darmstadt, Germany, calls the new work on element 117 “convincing.”

Most elements heavier than uranium, which has 92 protons, do not exist stably in nature and must be made artificially in the laboratory.

The Russians collaborated with U.S. researchers, including from Vanderbilt University and Oak Ridge National Laboratory in Tennessee, where the berkelium target was made. Berkelium, with atomic number 97, is another of the rare artificially produced elements; the Russian team was able to obtain just 22 milligrams of it from Oak Ridge.

The researchers briefly spotted signs of element 117 during two runs of collisions lasting 70 days each. In their paper, the researchers report observing the heavier isotope of element 117 decay with a half-life of 78 milliseconds; they measured the lighter one’s half-life at 14 milliseconds.

The new element, which has yet to be named, slips into a place on the periodic table between elements 116 and 118, both of which have already been discovered. Such superheavy elements are usually very radioactive and decay away almost instantly. But many researchers think it is possible that even heavier elements may occupy an “island of stability” in which superheavy atoms stick around for a while.

The new work supports that view. Analyses of the new element’s radioactive decay, Oganessian’s team writes in the new paper, “represent an experimental verification for the existence of the predicted ‘Island of Stability’ for super-heavy elements.”

Hofmann says that one of the most interesting things about the new work is the different products that result when the two element 117 isotopes decay. The isotope with 177 neutrons decays down to dubnium (atomic number 105), whereas the isotope with 176 neutrons decays down to roentgenium (atomic number 111). Comparing the two chains, Hofmann says, will help researchers better understand the characteristics of superheavy elements.

Element 117 is tentatively known as ununseptium. After its existence is confirmed, it will receive a permanent name, suggested by the discoverers, from the International Union of Pure and Applied Chemistry – a process that can take some time. In February 2010, the IUPAC finally granted the name copernicium to element 112, which was first produced by Hofmann’s group in 1996.

MADAM MARIE CURIE By Sulekha Rani.R,P.G.T Chemistry KV NTPC Kayamkulam AT A GLANCE: Marie Curie is best known as the discoverer of the radioactive elements polonium and radium and as the first person to win two Nobel prizes. For scientists and the public, her radium was a key to a basic change in our understanding of matter and energy. Her work not only influenced the development of fundamental science but also ushered in a new era in medical research and treatment.
Inventor: Marie Curie (aka Marie Sklodowska) Criteria; First to patent. First practical. Birth: November 7, 1867 in Warsaw, Poland Death: July 4, 1934 in Haute Savoie Nationality: Polish
Invention: Study of radioactivity, discoverer of polonium and radium Function: noun / Symbol Po and Ra Definition: A rare, brilliant white, luminescent, highly radioactive metallic element found in very small amounts in uranium ores. It is used in cancer radiotherapy, as a neutron source for some research purposes, and as a constituent of luminescent paints. Polonium atomic number 84 and Radium atomic number 88
Milestones: CAPS: Curie, Marie Curie, Marie Sklodowska, Marie Sklodowska Curie, Pierre Curie, Irène Joliot-Curie, Marcel Brillouin, Paul Painlevé, Gabriel Lippmann, and Paul Appell, ARY, radioactivity, polonium, radium, SIP, history, biography, inventor The Story: Madame Marie Curie was the world’s most famous woman scientist--and so she remains today. With her husband, Pierre Curie, and the French physicist Henri Becquerel, and later on her own, Curie pioneered the study of radioactivity (a word she coined). Marie Sklodowska, as she was called before marriage, was born in Warsaw in 1867. Both her parents were teachers who believed deeply in the importance of education. Marie had her first lessons in physics and chemistry from her father. She had a brilliant aptitude for study and a great thirst for knowledge; however, advanced study was not possible for women in Poland. Marie dreamed of being able to study at the Sorbonne in Paris, but this was beyond the means of her family. To solve the problem, Marie and her elder sister, Bronya, came to an arrangement: Marie should go to work as a governess and help her sister with the money she managed to save so that Bronya could study medicine at the Sorbonne. When Bronya had taken her degree she, in her turn, would contribute to the cost of Marie's studies. So it was not until she was 24 that Marie came to Paris to study mathematics and physics. Bronya was now married to a doctor of Polish origin, and it was at Bronya's urgent invitation to come and live with them that Marie took the step of leaving for Paris. By then she had been away from her studies for six years, nor had she had any training in understanding rapidly spoken French. But her keen interest in studying and her joy at being at the Sorbonne with all its opportunities helped her surmount all difficulties. To save herself a two-hours' journey, she rented a little attic in the Quartier Latin. There the cold was so intense that at night she had to pile on everything she had in the way of clothing so as to be able to sleep. But as compensation for all her privations she had total freedom to be able to devote herself wholly to her studies. "It was like a new world opened to me, the world of science, which I was at last permitted to know in all liberty", she writes. And it was France's leading mathematicians and physicists whom she was able to go to hear, people with names we now encounter in the history of science: Marcel Brillouin, Paul Painlevé, Gabriel Lippmann, and Paul Appell. After two years, when she took her degree in physics in 1893, she headed the list of candidates and, in the following year, she came second in a degree in mathematics. After three years she had brilliantly passed examinations in physics and mathematics. Her goal was to take a teacher's diploma and then to return to Poland. She met Pierre Curie in 1894, and they married in 1895. Marie Curie was interested in the recent discoveries of radiation. Wilhelm Conrad Roentgen had discovered X rays in 1895, and in 1896 Antoine Henri Becquerel had discovered that the element uranium gives off similar invisible radiations. Curie thus began studying uranium radiations, and, using piezoelectric techniques devised by her husband, carefully measured the radiations in pitchblende, an ore containing uranium. When she found that the radiations from the ore were more intense than those from uranium itself, she realized that unknown elements, even more radioactive than uranium, must be present. Marie Curie was the first to use the term radioactive to describe elements that give off radiations as their nuclei break down.Pierre Curie ended his own work on magnetism to join his wife's research, and in 1898 the Curies announced their discovery of two new elements: radium and polonium (named by Marie in honor of Poland). During the next four years the Curies, working in a leaky wooden shed, processed a ton of pitchblende, laboriously isolating from it a fraction of a gram of radium. They shared the 1903 Nobel Prize in physics with Becquerel for the discovery of radioactive elements. Marie Curie was the first female recipient of a Nobel Prize, it was the first time a woman had ever won a Nobel. In 1911, Curie became the first and only woman to win a second Nobel Prize. She earned, on her own, the award in chemistry for isolating pure radium. Pierre's life ended on April 19, 1906, when he was run over by a horse-drawn cart. His wife took over his classes and continued her own research. In 1911 she received an unprecedented second Nobel Prize, this time in chemistry, for her work on radium and radium compounds. She became head of the Paris Institute of Radium in 1914 and helped found the Curie Institute. Marie Curie's final illness was diagnosed as pernicious anemia, caused by overexposure to radiation. She died in Haute Savoie on July 4, 1934.