What is a Supernova?



There was a star somewhere around the sky staying almost unnoticeable, and got burst out suddenly in to a blistering brightness; it's just a one more Supernova!--if not Nova.

The energy and light that was radiated in to the sky during the star's sudden outburst is so heavy that it can easily outshines the entire galaxy--for several weeks to several months depending on the star's mass-- where it resides in, and that happens every time. The energy that got released during the process equals the entire energy that our sun can generate in its entire lifetime.

The star explodes and expels the material it was hiding till then, in to the surrounding Interstellar medium at a velocity of up to 30,000 km/s(10% that of light's). The material thus got released expands taking the help of a Shock wave that was generated during the sudden explosion, in the form of gas and dust called a Supernova remnant.

Supernova happens very rare compared with Nova, which is a completely different process and happens very often. For a galaxy in the size of our Milky way, supernova happens just once in every 50 years. Anyways, it's a lot more common process and happens once in every sec, when we look through the entire universe(as the universe breeds stars every sec and they are not eternal).

It's not that every star that exists in the universe can eventually turn in to a Supernova, but is entirely depends on the mass of the star. A star that which reaches a mass that is greater than 1.4 times that of our sun's, at the end of it's fuel consumption, will explode in to a Supernova. And that 1.4 limit was found by Chandrashekar and hence named after him as Chandrashekar limit.

Our sun according to chandrashekar can't turn in to a supernova but will end up as a
White dwarf, when it gets completely devoured of its fuel. And even no possibility of forming a Nova or Supernova later on as there is no binary neighbor, close by.

There are two types of supernova and I will try to explain them in my next post. :)

Check this one too..

What is a Nova?

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What is a Nova?


A Nova is not a new star that appears all of a sudden in the sky, as its name suggests. It's actually a sudden brightness that appears on the surface of an existing white dwarf star in a binary system with another star.

The White dwarf star's gravity starts pulling off the material that lies on its binary neighbor, when it is close enough. This material that got accumulated on the surface of the white dwarf mostly contains hydrogen atoms. and occasionally, they got hot enough to start a nuclear fusion and the process begins suddenly. The hydrogen atoms on the surface of the white dwarf gets fused in to the helium atoms and in turn makes the star shine brightly.

This process continues until the other star gets completely devoured of matter, and it ranges from a few days to almost thousands of years.

Nova should not be confused with Supernova, which completely is a different process. Earlier it was thought that Supernova is a kind of very bright Nova and hence the name. Nova happens very often in the space, not like a Supernova, which appears very rare.

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What is a Quasar?


Do you ever wondered, whether all those things that twinkles in the sky are stars?
well, twinkling is not just for stars. There are some far more interesting space objects that live under the mask of a star, and you can never distinguish them from stars unless your telescope is made to detect infrared radiation.

Quasars, this is what they--good scientists :-)--named them as they are quasi-stellar radio sources.

Quasar actually is a compact object like star rather than a expanded one like galaxy, surrounding a super massive black hole that lie at the center of a super massive galaxy. This super massive black hole in fact is responsible for all the power it is exhibiting.

They are by far the most luminous, most powerful and most energetic objects in the universe.
The energy they emit is in the range of about 1000 times that of the galaxies they inhabit in. They even show the heavy red shift (if a light source accelerates away from us, it appears more and more red) from earth, and that means they are moving faster away from earth and when combined with Hubble's law (galaxies tend to move away from each other with a velocity proportional to their distance) it shows that they are very very far from earth, and if this is the case, it can also implies that they are formed much early in the universe(as they traveled a lot of distance so far)

There are some very high radiating quasars in our known universe and their radiation almost equals trillion sun's--may be that's why they stay far away or is it the other way around. :-)

There is even a possibility that our Milky Way was once a quasar(according to NASA), may be because they didn't found any quasar at its center surrounding the massive black hole ;). The question is if it was once a quasar, what happened to the galaxy it was once surrounded by?

Check the video below to know how a quasar looks like:


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Cannibalism among galaxies


There was an old theory that described the most intriguing thing about galaxies and now it was proved, the theory that bigger galaxies try to feed on smaller galaxies when they come near, is no more an unproved theory but is a fact today. A recent study on the cannibalism of the galaxies helps the astronomers to hop in to some new areas that remained untouched so far.

Scientists who studied this phenomenon even confirmed that it happens and is already happened once in our close-by sister galaxy, Andromeda. However, it never happened with our Milky Way, as there are no wimpy galaxies nearby.

The process is so simple: when an wimpy galaxies tries to cross the bigger or not so wimpy galaxy, the not so lucky weaklings--stars--of the wimpy one are slowly swallowed up by the bigger one leaving behind the traces in the form of so-called tidal streams.

These tidal streams or trails that left behind can help us find the way the smaller galaxy once moved before getting ripped off. These paths can help us measure the bigger galaxies weight--if you are a maths geek--and the way they spread their mass--the bigger the weight, the sharper the change, in the path. They can even help us to know the way the galaxies are evolved...

"You can see these very complex systems of shells and plumes of tidal debris that mark the past accretion history of the galaxy," said astronomer Chris Mihos of case western Reserve University in Cleaveland, Ohio.

I don't know whether he is a geek of some sort or not but he definitely had found some tidal tails recently around some of the galaxies in the Virgo cluster, a relatively near by collection of galaxies about 50 million light years away.

There is one more study and is more interesting since it was not only led by Puragra Guhathakurtha of the University of California, Santa Cruz, but was regarding the cannibalism of Andromeda--our most near by galaxy, 2.5 million light-years away(It doesn't in any way mean that Mihos is less interesting).

He had found some tidal strams around the Andromeda galaxy and says that..

"The tidal steams gives you a window in time during which the events happened: the last couple billion years. If it was earlier, it's unlikely we'd still see the stars"

His discovery helps to set Andromeda apart from the Milky way.

"It looks like our sister galaxy has led a more exciting life," he said. "In contrast the Milky Way has had a relatively quiet, quiescent last couple billion years."

There are no signs of cannibalism around the Milky Way as it happens with Andromeda once. And I guess, we must feel happy for that. :)








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Sir Isaac Newton quotes

  • A man may imagine things that are false, but he can only understand things that are true, for if the things be false, the apprehension of them is not understanding. Isaac Newton quote
  • Errors are not in the art but in the artificers. Isaac Newton quote
  • I can calculate the motion of heavenly bodies, but not the madness of people. Isaac Newton quote
  • I was like a boy playing on the sea-shore, and diverting myself now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me. Isaac Newton quote
  • If I have done the public any service, it is due to my patient thought. Isaac Newton quote
  • If I have seen further than others, it is by standing upon the shoulders of giants. Isaac Newton quote
  • It is the weight, not numbers of experiments that is to be regarded. Isaac Newton quote
  • Tact is the art of making a point without making an enemy. Isaac Newton quote
  • To every action there is always opposed an equal reaction. Isaac Newton quote
  • To me there has never been a higher source of earthly honor or distinction than that connected with advances in science. Isaac Newton quote
  • To myself I am only a child playing on the beach, while vast oceans of truth lie undiscovered before me. Isaac Newton quote
  • We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances. Isaac Newton quote
  • We build too many walls and not enough bridges. Isaac Newton quote
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Einstein quotes
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Albert Einsteins best quotes

These are some of Einstein's quotes that I came came across..


  • Everything should be made as simple as possible, but not simpler. Albert Einstein quote
  • Common sense is the collection of prejudices acquired by age eighteen. Albert Einstein quote
  • The important thing is not to stop questioning. Curiosity has its own reason for existing. Albert Einstein quote
  • A man sits with a pretty girl for an hour, it seems like a minute. He sits on a hot stove for a minute, it's longer than any hour. That is relativity. Albert Einstein quote
  • Before God we are all equally wise - and equally foolish. Albert Einstein quote
  • A person starts to live when he can live outside himself. Albert Einstein quote
  • I am convinced that He (God) does not play dice. Albert Einstein quote
  • God is subtle but he is not malicious. Albert Einstein quote
  • I never think of the future - it comes soon enough. Albert Einstein quote
  • If we knew what we were doing, it wouldn't be called research, would it? Albert Einstein quote
  • Imagination is more important than knowledge, for knowledge is limited while imagination embraces the entire world. Albert Einstein quote
  • In the middle of difficulty lies opportunity. Albert Einstein quote
  • It is a miracle that curiosity survives formal education. Albert Einstein quote
  • Science without religion is lame, religion without science is blind. Albert Einstein quote
  • The secret to creativity is knowing how to hide your sources. Albert Einstein quote
  • Whoever undertakes to set himself up as a judge of Truth and Knowledge is shipwrecked by the laughter of the gods. Albert Einstein quote
  • Most people say that it is the intellect which makes a great scientist. They are wrong: it is character. Albert Einstein quote
  • Never do anything against conscience even if the state demands it. Albert Einstein quote
  • Try not to become a man of success but rather try to become a man of value. Albert Einstein quote
  • Bureaucracy is the death of all sound work. Albert Einstein quote
  • The high destiny of the individual is to serve rather than to rule. Albert Einstein quote
  • The true sign of intelligence is not knowledge but imagination. Albert Einstein quote
  • Nationalism is an infantile sickness. It is the measles of the human race. Albert Einstein quote
  • Relativity applies to physics, not ethics. Albert Einstein quote
  • Since the mathematicians have invaded the theory of relativity, I do not understand it myself anymore. Albert Einstein quote
  • I sometimes ask myself how it came about that I was the one to develop the theory of relativity. The reason, I think, is that a normal adult never stops to think about problems of space and time. These are things which he has thought about as a child. Albert Einstein quote
  • If my theory of relativity is proven successful, Germany will claim me as a German and France will declare that I am a citizen of the world. Should my theory prove untrue, France will say that I am a German and Germany will declare that I am a Jew. Albert Einstein quote
  • When the solution is simple, God is answering. Albert Einstein quote
  • Man usually avoids attributing cleverness to somebody else unless it is an enemy. Albert Einstein quote
  • I used to go away for weeks in a state of confusion. Albert Einstein quote
  • Dancers are the athletes of God. Albert Einstein quote
  • The intellect has little to do on the road to discovery. There comes a leap in consciousness, call it intuition or what you will, and the solution comes to you and you don't know how or why. Albert Einstein quote
  • Anyone who has never made a mistake has never tried anything new. Albert Einstein quote
  • Great spirits have often encountered violent opposition from weak minds. Albert Einstein quote
  • The value of a man resides in what he gives and not in what he is capable of receiving. Albert Einstein quote
  • The definition of insanity is doing the same thing over and over again and expecting a different result. Albert Einstein quote
  • We shall require a substantially new manner of thinking if mankind is to survive. Albert Einstein quote
  • Pure mathematics is, in its way, the poetry of logical ideas. Albert Einstein quote
  • The only thing that interferes with my learning is my education. Albert Einstein quote
  • God does not care about our mathematical difficulties. He integrates empirically. Albert Einstein quote
  • The whole of science is nothing more than a refinement of everyday thinking. Albert Einstein quote
  • Technological progress is like an axe in the hands of a pathological criminal. Albert Einstein quote
  • Peace cannot be kept by force. It can only be achieved by understanding.Albert Einstein quote
  • I like to think that the moon is there even if I am not looking at it. Albert Einstein quote
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Nearest black hole(or neutron star)


According to NASA, astronomers, using Chandra X-ray observatory had almost found a youngest possible Black hole known to exist in our cosmic background, and they even said that it appears to be our nearest possible. The 30-year-old object provides a unique opportunity for them to watch a black hole develop from infancy.

The black hole appears to be the remnant of SN 1979C, a supernova in the galaxy M100 approximately 50 million light years away from the earth. NASA's Swift satellite, the European Space Agency's XMM-Newton and the German ROSAT observatory revealed a steady flow of bright X rays from a source during their observation from 1995 to 2007. and suggests that this could be the black hole being fed through the material that is falling in to it from the supernova or possibly from a binary companion.

"If our interpretation is correct, this is the nearest example where the birth of a black hole has been observed," said Daniel Patnaude of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. who led the study.

Scientists think that the SN 1979C--first discovered by an amateur astronomer in 1979--was formed when a star about 20 times more massive than the sun collapsed--gravitational collapse.

SN1979C, obviously is different from other black holes that had been found so far, as it doesn't produce any Gamma-Ray Bursts (GRBs). GRBs are something, scientists relied on so far to found the black holes, but SN 1979C belongs to a class of supernovas unlikely to produce Gamma-Ray Bursts.

"This may be the first time the common way of making a black hole has been observed," said co-author Abraham Loeb, also of the Harvard-Smithsonian Center for Astrophysics. "However, it is very difficult to detect this type of black hole birth because decades of X-ray observations are needed to make the case."

The idea of a black hole with an observed age of only about 30 years is consistent with recent theoretical work. In 2005, a theory was presented that the bright optical light of this supernova was powered by a jet from a black hole that was unable to penetrate the hydrogen envelope of the star to form a GRB. X-ray data from Chandra and the other observatories fit this theory very well.

However they are not yet ready to confirm this--as a black hole--as there exists some intriguing possibility: A young, rapidly spinning neutron star with a powerful wind of high energy particles could be responsible for the X-ray emission.

Whatever the case could be, they can be still happy as this is our youngest neutron star so far and a brightest example of a "pulsar wind nebula". The Crab pulsar, the best-known example of a bright pulsar wind nebula, is about 950 years old.
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Kalpana chawla--Biography


KALPANA CHAWLA (PH.D.)
NASA ASTRONAUT (DECEASED)

PERSONAL DATA: Born in Karnal, India. Died on February 1, 2003 over the southern United States when Space Shuttle Columbia and the crew perished during entry, 16 minutes prior to scheduled landing. She is survived by her husband. Kalpana Chawla enjoyed flying, hiking, back-packing, and reading. She held a Certificated Flight Instructor's license with airplane and glider ratings, Commercial Pilot's licenses for single- and multi-engine land and seaplanes, and Gliders, and instrument rating for airplanes. She enjoyed flying aerobatics and tail-wheel airplanes.

EDUCATION: Graduated from Tagore School, Karnal, India, in 1976. Bachelor of science degree in aeronautical engineering from Punjab Engineering College, India, 1982. Master of science degree in aerospace engineering from University of Texas, 1984. Doctorate of philosophy in aerospace engineering from University of Colorado, 1988.

AWARDS: Posthumously awarded the Congressional Space Medal of Honor, the NASA Space Flight Medal, and the NASA Distinguished Service Medal.

EXPERIENCE: In 1988, Kalpana Chawla started work at NASA Ames Research Center in the area of powered-lift computational fluid dynamics. Her research concentrated on simulation of complex air flows encountered around aircraft such as the Harrier in "ground-effect." Following completion of this project she supported research in mapping of flow solvers to parallel computers, and testing of these solvers by carrying out powered lift computations. In 1993 Kalpana Chawla joined Overset Methods Inc., Los Altos, California, as Vice President and Research Scientist to form a team with other researchers specializing in simulation of moving multiple body problems. She was responsible for development and implementation of efficient techniques to perform aerodynamic optimization. Results of various projects that Kalpana Chawla participated in are documented in technical conference papers and journals.

NASA EXPERIENCE: Selected by NASA in December 1994, Kalpana Chawla reported to the Johnson Space Center in March 1995 as an astronaut candidate in the 15th Group of Astronauts. After completing a year of training and evaluation, she was assigned as crew representative to work technical issues for the Astronaut Office EVA/Robotics and Computer Branches. Her assignments included work on development of Robotic Situational Awareness Displays and testing space shuttle control software in the Shuttle Avionics Integration Laboratory. In November, 1996, Kalpana Chawla was assigned as mission specialist and prime robotic arm operator on STS-87. In January 1998, she was assigned as crew representative for shuttle and station flight crew equipment, and subsequently served as lead for Astronaut Offices Crew Systems and Habitability section. She flew on STS-87 (1997) and STS-107 (2003), logging 30 days, 14 hours and 54 minutes in space.

SPACE FLIGHT EXPERIENCE: STS-87 Columbia (November 19 to December 5, 1997). STS-87 was the fourth U.S Microgravity Payload flight and focused on experiments designed to study how the weightless environment of space affects various physical processes, and on observations of the Sun's outer atmospheric layers. Two members of the crew performed an EVA (spacewalk) which featured the manual capture of a Spartan satellite, in addition to testing EVA tools and procedures for future Space Station assembly. STS-87 made 252 orbits of the Earth, traveling 6.5 million miles in in 376 hours and 34 minutes.

STS-107 Columbia (January 16 to February 1, 2003). The 16-day flight was a dedicated science and research mission. Working 24 hours a day, in two alternating shifts, the crew successfully conducted approximately 80 experiments. The STS-107 mission ended abruptly on February 1, 2003 when Space Shuttle Columbia and the crew perished during entry, 16 minutes prior to scheduled landing.

from: www.jsc.nasa.gov
Check the video below to see what Sunita williams got to say about Kalpana chawla.


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Galileo galilei--Biography


Galileo Galilei was born on 15 February 1564 near Pisa, the son of a musician. He began to study medicine at the University of Pisa but changed to philosophy and mathematics. In 1589, he became professor of mathematics at Pisa. In 1592, he moved to become mathematics professor at the University of Padua, a position he held until 1610. During this time he worked on a variety of experiments, including the speed at which different objects fall, mechanics and pendulums.

In 1609, Galileo heard about the invention of the telescope in Holland. Without having seen an example, he constructed a superior version and made many astronomical discoveries. These included mountains and valleys on the surface of the moon, sunspots, the four largest moons of the planet Jupiter and the phases of the planet Venus. His work on astronomy made him famous and he was appointed court mathematician in Florence.

In 1614, Galileo was accused of heresy for his support of the Copernican theory that the sun was at the centre of the solar system. This was revolutionary at a time when most people believed the Earth was in this central position. In 1616, he was forbidden by the church from teaching or advocating these theories.

In 1632, he was again condemned for heresy after his book 'Dialogue Concerning the Two Chief World Systems' was published. This set out the arguments for and against the Copernican theory in the form of a discussion between two men. Galileo was summoned to appear before the Inquisition in Rome. He was convicted and sentenced to life imprisonment, later reduced to permanent house arrest at his villa in Arcetri, south of Florence. He was also forced to publicly withdraw his support for Copernican theory.

Although he was now going blind he continued to write. In 1638, his 'Discourses Concerning Two New Sciences' was published with Galileo's ideas on the laws of motion and the principles of mechanics. Galileo died in Arcetri on 8 January 1642.

from: bbc.co.uk

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Sir Isaac Newton--Biography


Isaac Newton was born on 4 January 1643 in Woolsthorpe, Lincolnshire. His father was a prosperous farmer, who died three months before Newton was born. His mother remarried and Newton was left in the care of his grandparents. In 1661, he went to Cambridge University where he became interested in mathematics, optics, physics and astronomy. In October 1665, a plague epidemic forced the university to close and Newton returned to Woolsthorpe. The two years he spent there were an extremely fruitful time during which he began to think about gravity. He also devoted time to optics and mathematics, working out his ideas about 'fluxions' (calculus).

In 1667, Newton returned to Cambridge, where he became a fellow of Trinity College. Two years later he was appointed second Lucasian professor of mathematics. It was Newton's reflecting telescope, made in 1668, that finally brought him to the attention of the scientific community and in 1672 he was made a fellow of the Royal Society. From the mid-1660s, Newton conducted a series of experiments on the composition of light, discovering that white light is composed of the same system of colours that can be seen in a rainbow and establishing the modern study of optics (or the behaviour of light). In 1704, Newton published 'The Opticks' which dealt with light and colour. He also studied and published works on history, theology and alchemy.

In 1687, with the support of his friend the astronomer Edmond Halley, Newton published his single greatest work, the 'Philosophiae Naturalis Principia Mathematica' ('Mathematical Principles of Natural Philosophy'). This showed how a universal force, gravity, applied to all objects in all parts of the universe.

In 1689, Newton was elected member of parliament for Cambridge University (1689 - 1690 and 1701 - 1702). In 1696,Newton was appointed warden of the Royal Mint, settling in London. He took his duties at the Mint very seriously and campaigned against corruption and inefficiency within the organisation. In 1703, he was elected president of the Royal Society, an office he held until his death. He was knighted in 1705.

Newton was a difficult man, prone to depression and often involved in bitter arguments with other scientists, but by the early 1700s he was the dominant figure in British and European science. He died on 31 March 1727 and was buried in Westminster Abbey.

from: bbc.co.uk

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Do you think its apple that led to the world's greatest discovery?

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Albert Einstein--Biography


Albert Einstein was born at Ulm in Baden-Wurttemberg, Germany, on March 14, 1879, into a non-observant Jewish family. At age five, his father showed him a pocket compass, and Einstein realized that something in "empty" space acted upon the needle; he would later describe the experience as one of the most revelatory of his life.

Although considered a slow learner, possibly due to dyslexia, simply shyness or the significantly rare and unusual structure his brain (examined after his death), Einstein built models and mechanical devices for fun. Another, more recent, theory about his mental development is that he had Asperger's syndrome, a condition related to autism.

Einstein began to learn mathematics around age 12. In 1894, his family moved from Munich to Pavia, Italy (near Milan), and this same year Einstein wrote his first scientific work, The Investigation of the State of Aether in Magnetic Fields.) He continued his education at Aarau, Switzerland, and in 1896, he entered the Swiss Federal Polytechnic School in Zurich to be trained as a teacher in physics and mathematics. In 1901, he gained his diploma and acquired Swiss citizenship. Unable to find a teaching post, he accepted a position as technical assistant in the Swiss Patent Office, obtaining his doctor's degree in 1905.

In 1908, Einstein was appointed Privadozent in Berne. The next year, he became Professor Extraordinary in Zurich, and in 1911 Professor of Theoretical Physics at Prague, returning to Zurich in 1912 to fill a similar post. In 1914, he was appointed Director of the Kaiser Wilhelm Physical Institute and Professor in the University of Berlin. He became a German citizen in 1914 and remained in Berlin until 1933, when he renounced his citizenship for political reasons and emigrated to America to take the position of Professor of Theoretical Physics at Princeton. He became a U.S. citizen in 1940 and retired from his post in 1945.

In his early days in Berlin, Einstein postulated that they correct interpretation of the special theory of relativity must also furnish a theory of gravitation, and in 1916 he published his paper on the general theory of relativity. During this time, he also contributed to the problems of the theory of radiation and statistical mechanics. In the 1920s, he embarked on the construction of unified field theories, continuing to work on the probabilistic interpretation of quantum theory, and he persevered with this work in America. He won the Nobel prize in 1921 "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect." He contributed to statistical mechanics by his development of the quantum theory of a monatomic gas, and he has also accomplished valuable work in connection with atomic transition probabilities and relativistic cosmology.

Einstein initially favored construction of the atomic bomb, in order to ensure that Hitler did not do so first, and even sent a letter, dated August 2, 1939, to President Roosevelt encouraging him to initiate a program to create a nuclear weapon. Roosevelt responded to this by setting up a committee for the investigation of using uranium as a weapon, which in a few years was superseded by the Manhattan Project.

After the war, however, Einstein lobbied for nuclear disarmament and a world government. Along with Albert Schweitzer and Bertrand Russell, he fought against nuclear tests and bombs. As his last public act, and just days before his death, he signed the Russell-Einstein Manifesto, which led to the Pugwash Conferences on Science and World Affairs.

Einstein's latter years were also spent searching for a unified field theory, for a universal force that would link gravitation with electromagnetic and subatomic forces, a problem on which no one to date has been entirely successful.

Einstein received honorary doctorate degrees in science, medicine and philosophy from many European and American universities. During the 1920s, he lectured in Europe, America and the Far East and was awarded Fellowships or Memberships to all of the leading scientific academies throughout the world. He gained numerous awards in recognition of his work, including the Copley Medal of the Royal Society of London in 1925, and the Franklin Medal of the Franklin Institute in 1935.

Einstein married Mileva Maric in 1903, and they had a daughter and two sons; the marriage was dissolved in 1919, and that same year he married his cousin Elsa Lowenthal, who died in 1936. Einstein died on April 18, 1955, in Princeton, New Jersey. Element 99 was named einsteinium (Es) in his honor.

from: atomicarchieve.com


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