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वह समाचार को सजाने और मसालेदार बनाने का काम करता है, वह तमाम सीमाओं के परे दर्शक को खीचने का माद्दा रखता है और सबसे बड़ी बात वह उन तमाम बातों को बड़े मज़े से कह सकता है जिन्हें खबर के साचे में ढाल कर कहना कई बार शायद उतना आसान न हो।

हरिवंश राय

Harivanshrai “Bachchan” Srivastava (November 27, 1907 - January 18, 2003) was a distinguished Hindi poet, perhaps best known for his early work Madhushala . He is also the father of Bollywood film superstar, Amitabh Bachchan.
He was born as Harivanshrai Srivastava into a Kayasth family on November 27, 1907 at a small town (of Patti, in district of Pratapgarh,U.P.) near Allahabad in the United Provinces (modern Uttar Pradesh). He was called “bachchan” (meaning ‘child’) at home. He received his formal schooling in a municipal school and followed the family tradition of attending Kayasth Paathshaalas to learn Urdu . He later studied at the Allahabad University and Banaras Hindu University. In this period, he came under the influence of the independence movement, then under the leadership of Mahatma Gandhi.
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He was born as Harivanshrai Srivastava into a Kayasth family on November 27, 1907
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In 1926, at the age of 19, Bachchan married his first wife, Shyama, who was then 14 years old. However she died ten years later in 1936 after a long spell of TB at just 24 years of age. Shortly after his first wife’s death, Bachchan married Teji Suri, a Sikh, in 1941. The marriage produced two sons, Amitabh and Ajitabh.
From 1941 to 1952 he taught English at the Allahabad University and then spent two years at Cambridge University in St Catharine’s College, Cambridge. There he studied with the famous English literature don, Thomas Rice Henn, and received a doctorate in English Literature for his work on the Irish poet W.B. Yeats. It was then, that he used ‘Bachchan’ as his last name instead of Srivastav. Bachchan was the second Indian to get his doctorate in English literature from Cambridge University.
Returning to India, he taught briefly and then worked as a producer for All India Radio, Allahabad. In 1955, Harivanshrai moved to Delhi to join the Ministry of External Affairs of the Government of India and there he was closely involved with the evolution of Hindi as the official language of the nation.
Bachchan used to introduce himself as Mitti ka tan, masti ka man, kshan-bhar jivan ? mera parichay. (A body of clay, a mind full of play, a moment?s life - that is me).Harivanshrai Bachchan died on January 18, 2003, at the age of 95, as a result of various respiratory ailments.

कोमेट्स 2

Science Background:
The following information provides teachers with some additional facts about comets. Teachers may use this information as a reference or use the questions to stimulate class discussion. The science questions support the lesson's activities.
1. What is a comet?
Comets are small, fragile, irregularly shaped bodies composed mostly of a mixture of water ice, dust, and carbon- and silicon-based compounds. They have orbits that repeatedly bring them very close to the Sun and then swing them into space. Comets have three distinct parts: a nucleus, a coma, and a tail. The solid core is called the nucleus, which develops a coma with one or more tails when a comet sweeps close to the Sun. The coma is the dusty, fuzzy cloud around the nucleus of a comet, and the tail extends from the comet and points away from the Sun. The coma and tails of a comet are transient features, present only when the comet is near the Sun.

Comets are small, fragile, irregularly shaped bodies composed mostly of a mixture of water ice, dust, and carbon- and silicon-based compounds
2. How did comets form?
Our entire solar system, including comets, formed from the collapse of a giant, diffuse cloud of gas and dust about 4.5 billion years ago. When the cloud started its collapse, it was rotating very slowly. But the cloud began to heat up and whirl faster as it shrank, just as twirling ice skaters spin faster by bringing their arms close to their bodies. The fast rotation helped ensure that not all of the material fell into the core. Instead, the material in the fast-spinning cloud spread out into a flattened disk. Meanwhile, the temperature in the dense, central core was heating up. The core eventually became so hot that it ignited nuclear fusion, creating the Sun. The disk's outer regions, however, were quite cold. The low temperatures allowed water to freeze onto dust grains, which grew in size to make clumps. Some clumps eventually reached a size of several kilometers in diameter. The clumps then began merging, probably by collisions, and formed the planets. Many theories abound about how these clumps became planets. This topic is at the forefront of scientific research. Whatever the details, large planets were created from the buildup of clumps of matter and gas from the surrounding cloud. But some of this matter did not merge into planets. Within the last decade, for example, astronomers discovered leftover clumps, called planetesimals, in a region beyond Neptune, although no large planets formed beyond that planet. These bodies form an outer asteroid belt at the edge of the solar system, called the Edgeworth-Kuiper belt, named for the scientists who proposed its existence in the 1950's. Recent calculations show that this asteroid-rich Kuiper belt (as it is now known) is probably the source of most of the short-period comets, such as Halley's comet, which orbits the Sun every 76 years.
3. Why do comets have tails?
A comet's tail is its most distinctive feature. As a comet approaches the Sun it develops an enormous tail of luminous material that extends for millions of kilometers away from the Sun. When far from the Sun, a comet's nucleus is very cold and its material is frozen. Water ice, as well as other compounds such as carbon dioxide and carbon monoxide ice, may be found in the nucleus. This icy nucleus changes radically when a comet approaches the Sun. The intense solar wind from the Sun transforms the solid nucleus directly into a vapor, bypassing the liquid phase. This process is called sublimation. The vapor helps stir things up in the nucleus, forcing the core to form a cloud-like mixture of gas and dust around it, called the coma. There, sunlight and the solar wind interact with the ingredients, creating the tails. The ingredients in the coma determine the types and number of tails. Some comets may appear to have no tails, but they really do. They are simply very faint. Scientists can identify these tails by using special filters that are sensitive to dust or gas emissions. Other comets, like Hale-Bopp, which could be seen from Earth in 1997, have very prominent tails. Although Hale-Bopp's tails could be seen visibly from Earth, scientists using sensitive cameras identified a much more complicated tail structure. One of these images revealed a long, curving dust tail. Other pictures showed dust and gas ion tails. There was even an image of a dust tail and two gas ion tails. The different tails provide scientists with important information about the internal chemistry and structure of a comet's nucleus.
4. What are the types of comet tails?
There are two types of comet tails: dust and gas ion. A dust tail, which is usually yellow, contains small, solid particles that are about the same size as those found in cigarette smoke. This tail forms because sunlight acts on these small particles, gently pushing them away from the comet's nucleus. Because the pressure from sunlight is relatively weak, the dust particles end up forming a diffuse, curved tail. A gas ion tail, which is usually blue, forms when ultraviolet sunlight rips one or more electrons from gas atoms in the coma, making them into ions (a process called ionization). A solar wind then carries these ions straight outward away from the Sun. The resulting tail is straighter and narrower. Both types of tails may extend millions of kilometers into space. As a comet heads away from the Sun, its tail dissipates, its coma disappears, and the matter contained in its nucleus freezes into a rock-like material. Recent observations of the very bright comet Hale-Bopp pinpointed a tail made of sodium (Na), a relative of the gas ion tail. This tail forms when sunlight pushes on sodium atoms released from the nucleus.
5. What is the difference between a meteor, a meteoroid, a meteorite, an asteroid and a comet?
Most of us probably have seen meteors or shooting stars. A meteor is the flash of light that we see in the night sky caused by the friction of a meteoroid passing through our atmosphere. A meteoroid is an interplanetary chunk of matter smaller than a kilometer and frequently millimeters in size. (Note that the term "meteor" refers to the flash of light caused by the meteoroid, not the meteoroid itself.) Most meteoroids that enter the Earth's atmosphere are so small that they vaporize completely and never reach the planet's surface. If any part of a meteoroid survives the fall through the atmosphere and lands on Earth, it is called a meteorite. Although the vast majority of meteorites are very small, their size can range from about a fraction of a gram (the size of a pebble) to 100 kilograms or more (the size of a huge, Earth-destroying boulder). Asteroids are generally larger chunks of rock that come from the asteroid belt located between the orbits of Mars and Jupiter. Comets are asteroid-like objects covered with ice, methane, ammonia, and other compounds that form a coma and sometimes a visible tail whenever they orbit close to the Sun. As a comet rides through the solar system, it leaves little particles in its wake. If the Earth's orbit intersects this "wake" of particles, we see a meteor shower as the particles rain down through Earth's atmosphere.
6. Where do comets come from?
Comets are found in two main regions of the cosmos: the Kuiper belt and the Oort cloud. Short-period comets — comets that frequently return to the solar system — probably originate from an area called the Kuiper belt. This belt is located within the solar system's ecliptic plane, beyond the orbit of Neptune. Astronomers found the first object in the Kuiper belt in 1992. Since that discovery many objects have been discovered within that region. These objects are usually small compared with planets. Their size ranges from 10 to 100 kilometers in diameter. Earth's diameter, for comparison, is 14,000 kilometers. The Hubble Space Telescope may have detected a population of small comets dwelling in this region in space. Based upon the Hubble observations, astronomers estimate that this belt contains at least 200 million comets, which are thought to have remained essentially unchanged since the birth of the solar system 4.5 billion years ago. Long-period comets are thought to emanate from a vast, spherical cloud of frozen bodies called the Oort cloud, named for the Dutch astronomer Jan Hendrik Oort. This cloud of comets, which also orbits the Sun, resides in the farthest region of the solar system, beyond Neptune and Pluto. The Oort cloud objects are made up of matter such as frozen ammonia ( ), methane ( ), hydrogen cyanide ( ), water ice ( ), and rock. Occasionally, a gravitational disturbance caused by a passing star or an interstellar cloud causes one of these bodies in the Oort cloud to begin a journey toward the inner solar system, where it makes a passing rendezvous with our Sun.

Comets

Comets are small, fragile, irregularly shaped bodies composed mostly of a mixture of water ice, dust, and carbon- and silicon-based compounds. They have orbits that repeatedly bring them very close to the Sun and then swing them into space. Comets have three distinct parts: a nucleus, a coma, and a tail. The solid core is called the nucleus, which develops a coma with one or more tails when a comet sweeps close to the Sun. The coma is the dusty, fuzzy cloud around the nucleus of a comet, and the tail extends from the comet and points away from the Sun. The coma and tails of a comet are transient features, present only when the comet is near the Sun.