Hi My Friends: A VUELO DE UN QUINDE EL BLOG., This one is the biography of the great astronomer:
Johannes Kepler (German pronunciation: [ˈkʰɛplɐ]; December 27, 1571 – November 15, 1630) was a German mathematician, astronomer and astrologer. A key figure in the 17th century scientific revolution, he is best known for his eponymous laws of planetary motion, codified by later astronomers, based on his works Astronomia nova, Harmonices Mundi, and Epitome of Copernican Astronomy. These works also provided one of the foundations for Isaac Newton's theory of universal gravitation.
During his career, Kepler was a mathematics teacher at a seminary school in Graz, Austria, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to astronomer Tycho Brahe, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He was also a mathematics teacher in Linz, Austria, and an adviser to General Wallenstein. Additionally, he did fundamental work in the field of optics, invented an improved version of the refracting telescope (the Keplerian Telescope), and mentioned the telescopic discoveries of his contemporary Galileo Galilei.
Kepler lived in an era when there was no clear distinction between
astronomy and astrology, but there was a strong division between
astronomy (a branch of mathematics within the liberal arts) and physics (a branch of natural philosophy).
Kepler also incorporated religious arguments and reasoning into his
work, motivated by the religious conviction and belief that God had
created the world according to an intelligible plan that is accessible
through the natural light of reason.[1] Kepler described his new astronomy as "celestial physics",[2] as "an excursion into Aristotle's Metaphysics",[3] and as "a supplement to Aristotle's On the Heavens",[4] transforming the ancient tradition of physical cosmology by treating astronomy as part of a universal mathematical physics.[5]
Wikipedia.
| A 1610 portrait of Johannes Kepler by an unknown artist | |
| Born | December 27, 1571 Free Imperial City of Weil der Stadt near Stuttgart, HRE (now part of the Stuttgart Region of Baden-Württemberg, Germany) |
|---|---|
| Died | November 15, 1630 (aged 58) Regensburg, Electorate of Bavaria, HRE (now Germany) |
| Residence | Germany |
| Nationality | German |
| Fields | Astronomy, astrology, mathematics and natural philosophy |
| Institutions | University of Linz |
| Alma mater | University of Tübingen |
| Known for | Kepler's laws of planetary motion Kepler conjecture |
Signature | |
In 1604, a new
star appeared in the night sky that was much brighter than Jupiter and
dimmed over several weeks. This event was witnessed by sky watchers
including the famous astronomer Johannes Kepler. Centuries later, the
debris from this exploded star is known as the Kepler supernova remnant.
Astronomers have long studied the Kepler supernova remnant and tried to
determine exactly what happened when the star exploded to create it. New
analysis of a long observation from NASA’s Chandra X-ray Observatory is
providing more clues. This analysis suggests that the supernova
explosion was not only more powerful, but might have also occurred at a
greater distance, than previously thought.
This image shows the Chandra data derived from more than eight days worth of observing time. The X-rays are shown in five colors from lower to higher energies: red, yellow, green, blue, and purple. These various X-ray slices were then combined with an optical image from the Digitized Sky Survey, showing stars in the field.
Previous analysis of this Chandra image has determined that the stellar explosion that created Kepler was what astronomers call a “Type Ia” supernova. This class of supernovas occurs when a white dwarf gains mass, either by pulling gas off a companion star or merging with another white dwarf, until it becomes unstable and is destroyed by a thermonuclear explosion.
Unlike other well-known Type Ia supernovas and their remnants, Kepler’s debris field is being strongly shaped by what it is running into. More specifically, most Type Ia supernova remnants are very symmetrical, but the Kepler remnant is asymmetrical with a bright arc of X-ray emission in its northern region. This indicates the expanding ball of debris from the supernova explosion is plowing into the gas and dust around the now-dead star.
The bright X-ray arc can be explained in two ways. In one model, the pre-supernova star and its companion were moving through the interstellar gas and losing mass at a significant rate via a wind, creating a bow shock wave similar to that of a boat moving through water. Another possibility is that the X-ray arc is caused by debris from the supernova expanding into an interstellar cloud of gradually increasing density.
The wind and bow shock model described above requires that the Kepler supernova remnant is located at a distance of more than 23,000 light years. In the latter alternative, the gas into which the remnant is expanding has higher density than average, and the distance of the remnant from the earth is between about 16,000 and 20,000 light years. Both alternatives give greater distances than the commonly used value of 13,000 light years.
In either model, the X-ray spectrum -- that is, the amount of X-rays produced at different energies -- reveals the presence of a large amount of iron, and indicates an explosion more energetic than the average Type Ia supernova. Additionally, to explain the observed X-ray spectrum in this model, a small cavity must have been cleared out around the star before it exploded. Such a cavity, which would have a diameter less than a tenth that of the remnant’s current size, might have been produced by a fast, dense outflow from the surface of the white dwarf before it exploded, as predicted by some models of Type Ia supernovas.
Evidence for an unusually powerful Type Ia supernova has previously been observed in another remnant with Chandra and an optical telescope. These results were independently verified by subsequent observations of light from the original supernova explosion that bounced off gas clouds, a phenomenon called light echoes. This other remnant is located in the Large Magellanic Cloud, a small galaxy about 160,000 light years from Earth, making it much farther away than Kepler and therefore more difficult to study.
These results were published in the September 1st, 2012 edition of The Astrophysical Journal. The authors of this study are Daniel Patnaude from the Smithsonian Astrophysical Observatory in Cambridge, MA; Carles Badenes from University of Pittsburgh in Pittsburgh, PA; Sangwook Park from the University of Texas at Arlington, TX, and Martin Laming from the Naval Research Laboratory in Washington DC.
NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.
Credits: X-ray: NASA/CXC/SAO/D.Patnaude, Optical: DSS
› Read more/access all images
› Chandra's Flickr photoset
This image shows the Chandra data derived from more than eight days worth of observing time. The X-rays are shown in five colors from lower to higher energies: red, yellow, green, blue, and purple. These various X-ray slices were then combined with an optical image from the Digitized Sky Survey, showing stars in the field.
Previous analysis of this Chandra image has determined that the stellar explosion that created Kepler was what astronomers call a “Type Ia” supernova. This class of supernovas occurs when a white dwarf gains mass, either by pulling gas off a companion star or merging with another white dwarf, until it becomes unstable and is destroyed by a thermonuclear explosion.
Unlike other well-known Type Ia supernovas and their remnants, Kepler’s debris field is being strongly shaped by what it is running into. More specifically, most Type Ia supernova remnants are very symmetrical, but the Kepler remnant is asymmetrical with a bright arc of X-ray emission in its northern region. This indicates the expanding ball of debris from the supernova explosion is plowing into the gas and dust around the now-dead star.
The bright X-ray arc can be explained in two ways. In one model, the pre-supernova star and its companion were moving through the interstellar gas and losing mass at a significant rate via a wind, creating a bow shock wave similar to that of a boat moving through water. Another possibility is that the X-ray arc is caused by debris from the supernova expanding into an interstellar cloud of gradually increasing density.
The wind and bow shock model described above requires that the Kepler supernova remnant is located at a distance of more than 23,000 light years. In the latter alternative, the gas into which the remnant is expanding has higher density than average, and the distance of the remnant from the earth is between about 16,000 and 20,000 light years. Both alternatives give greater distances than the commonly used value of 13,000 light years.
In either model, the X-ray spectrum -- that is, the amount of X-rays produced at different energies -- reveals the presence of a large amount of iron, and indicates an explosion more energetic than the average Type Ia supernova. Additionally, to explain the observed X-ray spectrum in this model, a small cavity must have been cleared out around the star before it exploded. Such a cavity, which would have a diameter less than a tenth that of the remnant’s current size, might have been produced by a fast, dense outflow from the surface of the white dwarf before it exploded, as predicted by some models of Type Ia supernovas.
Evidence for an unusually powerful Type Ia supernova has previously been observed in another remnant with Chandra and an optical telescope. These results were independently verified by subsequent observations of light from the original supernova explosion that bounced off gas clouds, a phenomenon called light echoes. This other remnant is located in the Large Magellanic Cloud, a small galaxy about 160,000 light years from Earth, making it much farther away than Kepler and therefore more difficult to study.
These results were published in the September 1st, 2012 edition of The Astrophysical Journal. The authors of this study are Daniel Patnaude from the Smithsonian Astrophysical Observatory in Cambridge, MA; Carles Badenes from University of Pittsburgh in Pittsburgh, PA; Sangwook Park from the University of Texas at Arlington, TX, and Martin Laming from the Naval Research Laboratory in Washington DC.
NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.
Credits: X-ray: NASA/CXC/SAO/D.Patnaude, Optical: DSS
› Read more/access all images
› Chandra's Flickr photoset
J.D. Harrington, 202-358-0321
Headquarters, Washington
j.d.harrington@nasa.gov
Janet Anderson, 256-544-0034
Marshall Space Flight Center, Huntsville, Ala.
janet.l.anderson@nasa.gov
Megan Watzke 617-496-7998
Chandra X-ray Center, Cambridge, Mass.
m.watzke@cfa.harvard.edu
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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