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  • Be stars are characterized by emission in Hydrogen Balmer lines thought to originate from a circumstellar disk. Recent observations by Rivinius et al. show that episodic brightenings in circumstellar emission are often correlated with period. — “Circumstellar Disk Formation by Radiatively Driven Orbital”, bartol.udel.edu
  • 10,000 AU, falls inward, feeding a central star and a circumstellar disk. pected trend: The circumstellar mass in Class 0 and I systems is d mi. — “Circumstellar Envelopes and Disks”, uapress.arizona.edu
  • The purpose of the Circumstellar Disk Learning Site (CDLS) is to introduce circumstellar debris disks to students, while also providing enough detail to be considered a significant resource for professional astronomy researchers and instructors. — “Circumstellar Disk Learning Site”,
  • Abstract:Mass-loss from massive stars leads to the formation of circumstellar wind-blown bubbles surrounding the star, bordered by a dense shell. Interaction of Supernova Remnants with a Circumstellar Shell V. V. Dwarkadas, 1995, AAS 187th Meeting. — “Vikram's Misc Page”, astro.uchicago.edu
  • "The circumstellar environment is where chemistry happens for the very first time," said Lodders. At the same time, the star begins to eject its outer layers into the interstellar medium by stellar winds, building up a circumstellar shell. — “Circumstellar Space: Where Stars Are Born”,
  • CIRCUMSTELLAR MASERS. Late-type giant and supergiant stars show maser emission in molecular transitions of hydroxyl, water, and silicon monoxide. The molecules are found in the circumstellar envelope produced by mass loss from the dying star. — “CIRCUMSTELLAR MASERS”, cv.nrao.edu
  • Acronym Finder: CSM stands for Circumstellar Material The meeting focused on active OB-stars as laboratories for the study of physical processes leading to stellar activity and the ejection of circumstellar material, particularly the orbiting disk that is central to rapidly rotating B-type stars. — “CSM - Circumstellar Material”,
  • circumstellar adj. Revolving around or surrounding a star. — “circumstellar: Definition from ”,
  • existing evidence of various circumstellar structures within the gas already present in the circumstellar envelope) approaches. the disc tangentially and. — “ASTRONOMY AND ASTROPHYSICS Circumstellar structures in the”,
  • In general, masers are associated with protostellar objects in star-forming regions and with late-type stars that lose their mass into circumstellar space. In detail, the maser characteristics are somewhat different in the various objects and molecular transitions. — “Masers, Interstellar and Circumstellar”, nedwww.ipac.caltech.edu
  • the circumstellar medium. Massive stars not only have strong winds, they also produce a ray burst has to pass through that part of the circumstellar medium, which has not yet. — “Formation and evolution of compact binaries”,
  • circumstellar. Definition from Wiktionary, the free dictionary. Jump to: navigation, search [edit] circumstellar (comparative more circumstellar, superlative most circumstellar) That. — “circumstellar - Wiktionary”,
  • Circumstellar Envelopes and Planetary Nebulae. The capabilities of the proposed array are well-suited to studies of the circumstellar environments of evolved stars and planetary nebulae (PNe) Recent theoretical studies of circumstellar matter in AGB stars, cool supergiants, and. — “Circumstellar Envelopes and Planetary Nebulae”, soral.as.arizona.edu
  • A circumstellar disk is a torus, pancake or ring-shaped accumulation of matter composed of gas, dust, planetesimals, asteroids or collision fragments in orbit around a star. Around the youngest stars, they are the reservoirs of material out of which planets may form. — “Circumstellar disk - Wikipedia, the free encyclopedia”,
  • As time proceeds, more and more of the rotating inflowing matter will fall onto the circumstellar disk rather than onto the star. circumstellar disk : The flattened distribution of gas that orbits the protostar and is. — “Astrobiology Institute at the University of Hawaii”, ifa.hawaii.edu
  • STRUCTURE AND EVOLUTION OF PRE-MAIN-SEQUENCE CIRCUMSTELLAR DISKS observations of the 1.3 mm continuum emission from circumstellar disks around 11 low- and intermediate-mass pre. — “STRUCTURE AND EVOLUTION OF PRE-MAIN-SEQUENCE CIRCUMSTELLAR DISKS”, astro.berkeley.edu
  • Catalog of Resolved Circumstellar Disks. Last updated: Oct 13 2010; maintained by Caer McCabe, Karl Stapelfeldt, and Carlotta Pham Contributing to the database. List of spatially resolved disks that have been withdrawn or refuted. Total number of disks: 148 (Pre-Main Sequence disks: 121, Debris Disks:. — “Catalog of Resolved Circumstellar Disks”,
  • Definition of circumstellar from Webster's New World College Dictionary. Meaning of circumstellar. Pronunciation of circumstellar. Definition of the word circumstellar. Origin of the word circumstellar. — “circumstellar - Definition of circumstellar at ”,
  • : Circumstellar disks Cosmic Dust: Dust, Molecule, Outer space, Interstellar medium, Nebula, Circumstellar disk, Planetary ring, Solar System, Zodiacal light, Asteroid belt, Kuiper belt, Stellar nucleosynthesis, Supernova by. — “: Circumstellar disks”,
  • Circumstellar Habitable Zones IV: What Makes a Friendly Neighborhood? In our circumstellar habitable zone, Venus was a bit too close, and likely experienced a moist runaway greenhouse effect thereby losing its oceans. — “ -- Circumstellar Habitable Zones IV: What Makes a”,
  • Numerical modeling of the structure of circumstellar disks. High contrast imaging for direct detection of extrasolar planets ( 2004) "The Visible and Near-infrared Dust Opaciy Law in the HH 30 Circumstellar Disk," Astrophysical Journal. — “Science - Origins of Stars and Planets: People: Karl Stapelfeldt”, science.jpl.nasa.gov
  • Translations of circumstellar. circumstellar synonyms, circumstellar antonyms. Information about circumstellar in the free online Their findings contribute to understanding the role of circumstellar disks in massive star formation in particular and to the birth of stars in. — “circumstellar - definition of circumstellar by the Free”,

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  • esetében bár ez valószínűleg inkább kivétel Sokkal gyakoribb a gyűrűs köd illetve a cirkumsztelláris burok jelenléte mint például az AG Car a He 3 519 a HR Car és a WRA 751 esetében A ledobott anyagról nyert megfigyelések például az η Car esetében illetve az LBV k atmoszférájának elemzése azt mutatja hogy nitrogénben és héliumban
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  • on a service night at the 4 2 m William Herschel Telescope 1993 February 16 ~210d after the SN exploded using ISIS at resolution about 8000 in excellent conditions seeing 1 arcsec The figure shows part of our long slit spectrum around H alpha with broad SN emission subtracted There s H II region emission adjacent to the supernova but the H alpha from the
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  • below are of the WN type If possible we could determine when dust formation occurs around these stars i e is it confined to old WC stars or can it start sooner in the WR s lifetime Candidate List for Possible New Dust Emitters Head back to my main page
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  • Page one of the Introduction Page two of the Introduction Page one of the Procedure
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  • Star formation occurs in dusty regions Stellar flux is reprocessed in the circumstellar environment and in the parent molecular cloud
  • of the stellar rotation cycle indicated at the top left of each panel Note that the circumstellar emission is dominated by two clouds edge on at phase 0 25 and face on at phase 0 75 Figure 4 Time series spectra of the varying circumstellar Hα emission observed from σ Ori E left phased on the 1 19 day rotation period of the star compared against the
  • NGC346inSMC jpg 20 Jan 2005 07 41 136K StarburstGalaxyNGC1808 HST jpg 31 Aug 2005 06 37 137K CircumstellarDebrisDisks HST jpg 19 Jan 2006 16 53 143K 47Tucanae HST jpeg 26 Mar 2004 06 21 147K
  • 嬰兒期太陽系的畫像 影像提供 N Grosso MPE
  • Page two of the Introduction Page one of the Procedure Page two of the Procedure
  • Page one of the Procedure Page two of the Procedure Page three of the Procedure
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  • field lines in a complex `snake pattern The darkest areas of the temperature plots represent gas at T ~ 107 K hot enough to produce relatively hard X ray emission of a few keV Figure 2 Density of a 2D MHD simulation for a star rotating at half the critical with moderate magnetic confinement shown at time snapshots of 90 ksec left and 390 ksec right after
  • Homunculus köd esetében bár ez valószínűleg inkább kivétel Sokkal gyakoribb a gyűrűs köd illetve a cirkumsztelláris burok jelenléte mint például az AG Car a He 3 519 a HR Car és a WRA 751 esetében A ledobott anyagról nyert megfigyelések például az η Car esetében illetve az LBV k atmoszférájának elemzése azt mutatja hogy nitrogénben és
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  • page will have several GIFs and JPEGs of the pieces of the paper that I have written and the graphs and figures which I think are important Here s the introduction and procedure sections Page one of the Introduction Page two of the Introduction
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  • to 05 AU and a gap between 2 5 and 10 AU Notice how the p=0 5 plot the plot that allows dust to be hotter at larger radii shows a significantly larger amount of infrared emission In an optically thin disk there are more parameters to worry about The density of the disk and the material of the disk play a larger role because we are able to observe emission from
  • például a Homunculus köd esetében bár ez valószínűleg inkább kivétel Sokkal gyakoribb a gyűrűs köd illetve a cirkumsztelláris burok jelenléte mint például az AG Car a He 3 519 a HR Car és a WRA 751 esetében A ledobott anyagról nyert megfigyelések például az η Car esetében illetve az LBV k atmoszférájának elemzése azt mutatja hogy
  • Page three of the Procedure References Here is a typical example of the IRAS data It shows what happens after 1 and 20 iterations The minimum entropy deconvolution process was used For more information about this
  • plasma 10 000 18 000K and of Si IV and Fe V lines from hot plasma 30 000K Examples of the faint absorptions from cool and hot plasma are shown in Figures 2 and 3 respectively Fig 2 Archival GHRS spectrum compliments of D Meyer of the region near the ISM O I line two sharp absorptions which also contains several broader features probably arising from
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  • We see here that a continuous disk that extends out from the surface of the star a distance 100 AU produces a smooth curve of excess infrared emission
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  • Discover the cosmos Each day a different image or photograph of our fascinating universe is featured along with a brief explanation written by a professional astronomer 2002 June 7 Portrait of an Infant Solar System Credit N Grosso
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  • Hot open questions What are the effects of rotation on stellar evolution nucleosynthesis and circumstellar nebulae Which binary systems can produce black holes which gamma ray bursts What are the
  • Circumstellar disk around HD 141569A
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Videos
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  • Planet Formation in Circumstellar Disk Jupiter-Mass planet opens a gap in a solar nebula. The gas around the planet is heated by the accretion of mass onto the planetary surface. The simulation was done by HH Klahr and W. Kley at the University of Tübingen. The ray tracer used is PovRay 3.5. The purpose of this tracing is not a physical model that accurately reproduces photometry at various wavelengths or other fancy physical parameters. The idea is to visualize the development of density and size scales during the collapse. No dust model (opacities, size distribution etc.) is assumed for the ray tracer. The colours seen in the image do not correspond to any actual wavelengths.
  • Herschel science - sequence one This animation shows the Sun being born and the planets of the Solar System forming from a disc of circumstellar material. Herschel will study the formation of stars and possible planetary systems around them in unprecedented detail. Credits: ESA (animation by Silicon Worlds)
  • Hovindism #1 Definition of Evolution Part 1 in our new weekly series dissecting the errors made by Creation Science Evangelism's Kent Hovind in his misguided attacks on biological science. References: 1) Merriam-Webster. 2004. The Merriam-Webster Dictionary. Merriiam-Webster. 2) Weinberg, S. 2008. Cosmology. Oxford University Press. 3) Hubble, E. 1929. A relation between distance and radial velocity among extra galactic nebulae. PNAS 15(3):168-173. 4) Fixsen DJ, Cheng ES, Gales JM, Mather JC, ShaFer RA, Wright EL. 1996. The Cosmic Microwave Background Spectrum from the Full Cobe1 Firas Data Set. Astrophysical Journal 473:576-587. 5) Reeves H. 1974. On the origin of the light elements. Annuak Review of Astronomy and Astrophysics 12:437-470. 6) The Supernova Cosmology Project. 2003. New Constraints on ΩM, ΩΛ, and w from an Independent Set of 11 High-Redshift Supernovae Observed with the Hubble Space Telescope. Astrophysical Journal. 598:102-137. 7) Kuo HM, Goldhaber G, Perlmutter S. 1998. A study of 42 type Ia supernovae and a resulting measurement of ΩM and ΩΛ. Physics Reports 307(1):325-331. 8) Ellis GFR. 1979. The homogeneity of the universe. General Relativity and Gravitation 11(4):281-289. 9) Misner CW. 1968. The isotropy of the universe. Astrophysical Journal 151:431-457. 10) Hoyle F. 1946. The synthesis of the elements from hydrogen. Monthly Notices of the Royal Astronomical Society 106:343-383. 11) Seeger PA, Fowler WA, Clayton DD. 1965. Nucleosynthesis of heavy elements by neutron capture ...
  • The Lame Excuse Handbook www.insectman.us www.insectman.us theinsectmanofwv has made a comment on The Lame Excuse Handbook: Name ONE peer reviewed paper by Dawkins that is about evolution. josephmastropaolo has made a comment on The Lame Excuse Handbook: You say you evolutionists have the scientific evidence and the creationists have none. If true, then take the creationists broke with mini-trials. Or if not true, if in fact you have no evidence, then we have nothing to discuss. josephmastropaolo has made a comment on The Lame Excuse Handbook: "Dr. Dawkins has produced over 30 peer reviewed science papers." He has not written one science paper, which to qualify must present objective, valid, reliable and calibrated evidence. He has admitted in writing that he does not even know what calibrated means. That is why he cannot win mini-trials and make himself a millionaire, and why he is # 14 on the Default Judgment List. Like the other 374000 evolutionists worldwide, he is merely a superstitious propaganda essayist. Pity. The comments from evolutionists about creation videos are just a distraction from the debate issue and would add nothing to a science controlled debate in a public forum. josephmastropaolo has made a comment on The Lame Excuse Handbook: "submitting a paper for peer review." It has been done over and over again. In your vast sea of ignorance, you also do not know this. You obviously have not searched the literature. You obviously do not know how. You obviously are a meddler, not a ...
  • Hovindism #1 the definition of evolution (part 1/2) Kent presents a number of logical fallacies References 1. Merriam-Webster. 2004. The Merriam-Webster Dictionary. Merriiam-Webster. 2. Weinberg, S. 2008. Cosmology. Oxford University Press. 3. Hubble, E. 1929. A relation between distance and radial velocity among extra galactic nebulae. PNAS 15(3):168-173. 4. Fixsen DJ, Cheng ES, Gales JM, Mather JC, ShaFer RA, Wright EL. 1996. The Cosmic Microwave Background Spectrum from the Full Cobe1 Firas Data Set. Astrophysical Journal 473:576-587. 5. Reeves H. 1974. On the origin of the light elements. Annuak Review of Astronomy and Astrophysics 12:437-470. 6. The Supernova Cosmology Project. 2003. New Constraints on [..], and w from an Independent Set of 11 High-Redshift Supernovae Observed with the Hubble Space Telescope. Astrophysical Journal. 598:102-137. 7. Kuo HM, Goldhaber G, Perlmutter S. 1998. A study of 42 type Ia supernovae and a resulting measurement of... Physics Reports 307(1):325-331. 8. Ellis GFR. 1979. The homogeneity of the universe. General Relativity and Gravitation 11(4):281-289. 9. Misner CW. 1968. The isotropy of the universe. Astrophysical Journal 151:431-457. 10. Hoyle F. 1946. The synthesis of the elements from hydrogen. Monthly Notices of the Royal Astronomical Society 106:343-383. 11. Seeger PA, Fowler WA, Clayton DD. 1965. Nucleosynthesis of heavy elements by neutron capture. Astrophysical Journal Supplement 11:121-166. 12. Bonnell IA, Bate MR. 2006. Star formation through gravitational collapse and ...
  • SN 1987A The unique supernova SN 1987A has been a bonanza for astrophysicists. It provided several observational firsts, like the detection of neutrinos from an exploding star, the observation of the progenitor star on archival photographic plates, the signatures of a non-spherical explosion, the direct observation of the radioactive elements produced during the blast, observation of the formation of dust in the supernova, as well as the detection of circumstellar and interstellar material. The footage available include images of the supernova taken in the past, as well as the most recent one obtained with ESOs Very Large Telescope, and images of the La Silla and Par*** Observatories. A breathtaking sequence that zooms-in from the Large Magellanic Cloud into the supernova is also available.
  • EX Lupi The fading light of a flaring young star has shed light on a puzzle involving crystals and comets... For the most part, the universe changes very slowly compared to, well, us. The stars appear much the same today as they did to our ancestors. So its a rare treat when astronomers actually catch a star 'in the act' of doing something unexpected, especially when it helps solve a long-standing puzzle. The star of this special event is about 500 light years away and known as EX Lupi. Its probably a close match to what our own Sun was like in its infancy almost 5 billion years ago. Early in 2008 it flared dramatically in brightness, due to material from its disk falling onto the central star. The stars brightness increased by a factor of 100, heating the disk far from the star. It appears that tiny dust particles far out in the disk melted slightly, or annealed. As they cooled they took on a new crystalline structure. This is the first time astronomers have ever caught crystals in the act of forming in a circumstellar disk. So how is it possible to detect such tiny crystals around a star thats so far away? Well, dust is a specialty of NASAs Spitzer Space Telescope. Not only has Spitzer shown that dusty disks are common around young stars, its infrared spectrograph also allows us to study their compositions. By splitting up its light into a spectrum, astronomers can look for unique features, like spectral fingerprints, that correspond to specific minerals. This first observation ...
  • The Evolution of a Planet-Forming Disk This animation shows the evolution of a planet-forming disk around a star. Initially, the young disk is bright and thick with dust, providing raw materials for building planets. In the first 10 million years or so, gaps appear within the disk as newborn planets coalesce out of the dust, clearing out a path. In time, this planetary "debris disk" thins out as gravitational interactions with numerous planets slowly sweep away the dust. Steady pressure from the starlight and solar winds also blows out the dust. After a few billion years, only a thin ring remains in the outermost reaches of the system, a faint echo of the once-brilliant disk. Our own solar system has a similar debris disk Ð a ring of comets called the Kuiper Belt. Leftover dust in the inner portion of the solar system is known as "zodiacal dust." Bright, young disks can be imaged directly by visible-light telescopes, such as NASA's Hubble Space Telescope. Older, fainter debris disks can be detected only by infrared telescopes like NASA's Spitzer Space Telescope, which sense the disks' dim heat. Credit: NASA/JPL-Caltech/R. Hurt (SSC)
  • Echo Music by William Byrd, Echo Galliard MB 114. Aapo Häkkinen, Harpsichord This sequence of pictures from the NASA/ESA Hubble Space Telescope's Advanced Camera for Surveys dramatically demonstrates the echoing of light through space caused by an unusual stellar outburst in January 2002. A burst of light from the bizarre star is spreading into space and reflecting off of surrounding shells of dust to reveal a spectacular, multicoloured bull's eye. This sequence of pictures from May to December 2002 shows apparent changes in the appearance of the circumstellar dust as different parts are illuminated sequentially. This effect is called a 'light echo'. From the first to last image the apparent diameter of the nebula appears to balloon from 4 to 7 light-years. This creates the illusion that the dust is expanding into space faster than the speed of light. In reality the dust shells are not expanding at all, but it is simply the light from the stellar flash that is sweeping out into the nebula. The different colours in the nebula reflect changes in the colour of the star during its outburst. The red star at the centre of the eyeball-like feature is an unusual erupting supergiant called V838 Monocerotis, located about 20 000 light-years away in the winter constellation Monoceros (the Unicorn). During its outburst the star brightened to more than 600 000 times our Sun's luminosity. The circular feature has now expanded to slightly larger than the angular size of Jupiter on the sky ...
  • MPL3D Solar System Rapid rotating stars There are well known stars that rotate around themselves every few hours. This causes an equatorial enlargement that can be observed at this video, as well as the circumstellar disks and the gravity darkening due to the high rotational velocities.
  • Protoplanetary Discs Around Baby Stars [1080p] A collection of 30 never-before-released images of embryonic planetary systems in the Orion Nebula are the highlight of the longest single Hubble Space Telescope project ever dedicated to the topic of star and planet formation. Also known as proplyds, or protoplanetary discs, these modest blobs surrounding baby stars are shedding light on the mechanism behind planet formation. Only the NASA/ESA Hubble Space Telescope, with its high resolution and sensitivity, can take such detailed pictures of circumstellar discs at optical wavelengths. In this animation, the process of proplyds forming within a nebula is illustrated. The bright proplyds, visible as shiny cusps, are illuminated by the star Theta 1 Orionis C, which sets the disc material ablaze. This is, however, both a blessing and a curse. The powerful radiation that lights them up also threatens their very existence, as the disc material, once heated up, is very likely to dissipate and dissolve before planets can form. Photos available at: Credit: ESA/Hubble (M. Kornmesser)
  • Supernova 1987A from 1996 to 2004 by Hubble Space Telescope Movie from the paper "Observing Supernova 1987A with the Refurbished Hubble Space Telescope," by Kevin France, Richard McCray, Kevin Heng, Robert P. Kirshner, Peter Challis, Patrice Bouchet, Arlin Crotts, Eli Dwek, Claes Fransson, Peter M. Garnavich, Josefin Larsson, Stephen S. Lawrence, Peter Lundqvist, Nino Panagia, Chun SJ Pun, Nathan Smith, Jesper Sollerman, George Sonneborn, John T. Stocke, Lifan Wang, J. Craig Wheeler. Published in Science, 7 September 2010. Supporting Online Material. "This movie displays the evolution of the remnant of SN1987A as observed by the Hubble Space Telescope. The rapidly fading and expanding central source is light from the inner radioactive supernova debris. The inner circumstellar ring is glowing initially because it was ionized by radiation from the supernova outburst. At about 1995, the first hotspot appeared at approximately 11 o'clock. Today, the ring is entirely encircled by hotspots. The radiation from the hotspots is caused by compression and heating that takes place when the supernova blast wave enters." Abstract: "Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 using the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Ly and H lines from shock emission continue to ...
  • Accretion Disk Formation This is a 3D CFD simulation of the formation of an accretion disk in a High Mass X-Ray Binary matching the parameters of LMC-X4.
  • Come Search With Me Part 4 by Dr. Subodh K Pandit Anthropic Principle A) Maintenance of Life "Take the expansion rate of the universe which is fine-tuned to one part in a trillion trillion trillion trillion trillion trillion. That is, if it were changed by one part in either direction - a little slower - we could not have a universe that would be capable of supporting life." Stephen Meyer PhD, Molecular Biology, History of Physics, Evolutionary Theory "...gravity has an incomprensibly narrow range for life to exist." Robin Collins Nuclear force is the strongest force we know. The weakest force we know is gravity. If you just move the setting of gravity 1 millimeter on a universe wide ruler, our earth will shrink to globe of 40 miles in diameter and all life will cease. Cosmological Constant (density of matter in space) "The fine tuning has conservatively been estimated to be at least one part iin a hundred million billion billion billion billion billion." Robin Collins. "When you combine the two (gravity and the cosmological constant), the fine tuning would be to a precision of one part in a hundred million trillion trillion trillion trillion trillion trillion. That would be the equivalent of one atom in the entire known universe." Robin Collins "...we happen to be situated safely between the Sagittarius and Perseus spiral arms...I really can't come up with an example of another place in the galaxy that is as friendly to life as our location. It's only in the very inner edge of the Circumstellar Habitable Zone where you ...
  • SN 1979C The youngest known black hole in our cosmic neighborhood may have been found using NASA's Chandra X-ray Observatory and other telescopes. Evidence for this very young black hole was found in a supernova called 1979C, seen to explode about 30 years ago. Dr. Dan Patnaude of the Harvard-Smithsonian Center for Astrophysics led this study and discusses it with us. In looking at this supernova, we actually went all the way back to the Einstein era and looked at the data from 1980 all the way up until now. This included data from Einstein, ROSAT, Chandra, SWIFT and XMM-Newton. Now Einstein didn't actually see the supernova, but ROSAT was able to observe it. When you compare the data from ROSAT moving forward, you actually see that this supernova is remarkably constant in its brightness. Now you don't expect this from a supernova. Generally, when a star explodes, it expands out into the circumstellar medium and the X-ray emission and all of the other emission drops with time. So this is actually rather remarkable. What we interpreted this as was the formation of a black hole in the center of the supernova. If this is the case then this would be evidence for the youngest and the nearest newly-formed black hole known to date. What makes this exceptional is that we haven't actually ever directly observed a black hole inside of a supernova. It's thought that they are formed in some type of supernova, but we've never actually observed them to date, so to actually see this would be ...
  • Formation of a "sun" and "planet" system with SPH v1 www.greenleaf.dk/tag 3000 particles are given initial position in a disk shape with a velocity that somewhat matches the orbital period arround the center og the disk. Random pertubations to position and velocity are added. The system is implemented using SPH and has viscosity and presure but not surface tension since surface tension is not a factor on this scale. The particle-particle gravitational forces are calculated using the Barnes Hutt method which changes the O(n^2) cost of gravity to O(n log n) by spatial subdivision and force approximations when appropiate. The simulation runs at 12 FPS for 3000 particles using four CPU cores and is implemented with c# and renders with windows GDI+ for the time beeing. The space has "walls" constraining the particles to the visible area. This is obviously something to change since it looks stupid when a planet smashes into the glass walls sorrounding the solar system ;-)
  • Formalhaut - Alpha Piscis Austrini Located just south of the ecliptic plane, Piscis Austrinus was one of the original 48 constellations charted by Ptolemy, and it remains one of the 88 modern constellations adopted by the IAU. Spanning 245 square degrees of sky, it ranks 60th in size. Piscis Austrinus contains 7 mains stars in its asterism and has 21 Bayer Flamsteed designated stars within its confines. It is bordered by the constellations of Capricornus, Microscopium, Grus, Sculptor and Aquarius. Piscis Austrinus can be seen by all observers located at latitudes between +55° and ?90° and is best seen at culmination during the month of October. Piscis Austrinus is also known as Piscis Australis Latin for the "Southern Fish". Prior to the 20th century, it was also known as Piscis Notius. In mythology it is said to represent the parent of Pisces. Perhaps the legend came from the Syrians who did not eat fish, but worshipped them as gods. The Greeks also kept fish ponds at their temples and one legend tells of woman who was turned into a mermaid when she threw herself into a pond in a suicide attempt. There are those who believe Pisces Austrinus is associated with the Assyrian fish god Dagon and the Babylonian god Oannes, but at least all accounts give a rather "fishy" tale! Let's begin our binocular tour of Piscis Austrinus with its brightest star Alpha the "a" symbol on our map. Alpha Piscis Austrini is best known as Formalhaut the "Mouth of the Whale". This class-A main sequence star is about 25 light years ...
  • A Tour of SN 1979C Listen Narrator: The youngest known black hole in our cosmic neighborhood may have been found using NASA's Chandra X-ray Observatory and other telescopes. Evidence for this very young black hole was found in a supernova called 1979C, seen to explode about 30 years ago. Dr. Dan Patnaude of the Harvard-Smithsonian Center for Astrophysics led this study and discusses it with us. Dan Patnaude: In looking at this supernova, we actually went all the way back to the Einstein era and looked at the data from 1980 all the way up until now. This included data from Einstein, ROSAT, Chandra (of course), SWIFT and XMM-Newton. Now Einstein didn't actually see the supernova, but ROSAT was able to observe it. When you compare the data from ROSAT moving forward, you actually see that this supernova is remarkably constant in its brightness. Now you don't expect this from a supernova. Generally, when a star explodes, it expands out into the circumstellar medium (or its surrounding material) and the X-ray emission and all of the other emission drops with time. So this is actually rather remarkable. What we interpreted this as was the formation of a black hole in the center of the supernova. If this is the case then this would be evidence for the youngest and the nearest newly-formed black hole known to date. What makes this exceptional is that we haven't actually ever directly observed a black hole inside of a supernova. It's thought that they are formed in some type of supernova, but we've ...
  • Birth Of An Unsual Planetary System This artist's animation shows a brown dwarf surrounded by a swirling disk of planet-building dust. NASA's Spitzer Space Telescope spotted such a disc around a surprisingly low-mass brown dwarf, or "failed star." The brown dwarf, called OTS 44, is only 15 times the size of Jupiter, making it the smallest brown dwarf known to host a planet-forming, or protoplanetary disk. Astronomers believe that this unusual system will eventually spawn planets. If so, they speculate that OTS 44's disk has enough mass to make one small gas giant and a few Earth-sized rocky planets. OTS 44 is about 2 million years old. At this relatively young age, brown dwarfs are warm and appear reddish in color. With age, they grow cooler and darker. Credit: NASA/JPL-Caltech/T. Pyle (SSC)
  • The Universe - Nebulas A nebula is an interstellar cloud of dust, hydrogen gas, helium gas and other ionized gases. Originally nebula was a general name for any extended astronomical object, including galaxies beyond the Milky Way. Nebulae often form star-forming regions. Formation: many nebulae or stars form from the gravitational collapse of gas in the interstellar medium. As the material collapses under its own weight, massive stars may form in the center, and their ultraviolet radiation ionises the surrounding gas, making it visible at optical wavelengths. Examples of these types of nebulae are the Rosette nebula and the Pelican nebula. The size of these nebulae varies depending on the size of the original cloud of gas. These are sites where star formation occurs. The formed stars are sometimes known as a young, loose cluster. Some nebulae are formed as the result of supernova explosions, the death throes of massive, short-lived stars. The material thrown off from the supernova explosion are ionized by the enrgy and the compact object that it can produce. One of the best examples of this is the Crab nebula, in Taurus. The supernova event was recorded in the year 1054 and is labelled SN 1054. The compact object that was created after the explosion lies in the center of the Crab Nebula and is a neutron star. Other nebulae may form as planetary nebulae. This is the final stage of a low-mass star's life, like Earth's Sun. Stars with a mass up to 8-10 solar masses evolve into red giants and ...
  • Karl Priest Checkmates the Board of Education Karl Priest the Insect man www.insectman.us Indoctrination Has Replaced Education Why has education failed us in the Twentieth Century? It has failed because it adopted the goals of social scientists as they lust for power. School is used to mold students for social science control. Students are not taught the basics. They are trained to conform. They are not taught what they must know to find out what they need to know....... http by Erica Carle I cannot imagine why you would pay any more attention to those calling names than you would the kibitzers at a ball game.The kibitzer does not have the talent to play the game. All he has to massage his ego is the stupidities he hurls at those who do have the talent. If he sees a lefty 0.387 batter coming up to the plate, then doesn't he yell, "Hey moron, you're holding your bat wrong. Get on the other side of the plate." He makes an ass of himself before 60000 fans, then at the bar after the game he loudly proclaims that the batter could have hit four home runs instead of three if only he had changed his grip and stood on the other side of the plate. Everyone at the bar cheers his wisdom because he has bought the last five rounds of drinks. He staggers home mumbling that he could have been greater than Babe Ruth or Joe DiMaggio or Mickey Mantle or any of those other nutcase sandlot players. When he goes down the subway steps, he stumbles and has to continuously hold on to the bannister. When he passes the schoolyard, he picks up ...
  • The Proplyds of M42 - Protoplanetary discs of the Orion Nebula Slideshow portraying 30 pictures of protoplanetary discs (=proplyds) discovered by astronomers of the Hubble Space Telescope (HST) in the Orion Nebula (also known as Messier 42 or NGC 1976). The proplyds are formed from rotating circumstellar discs of dense gas surrounding a young newly formed star. The discs may also contain debris from other materials besides gas (dust grains, for example), which facilitate the formation of gas-giant planets similar to Jupiter or Saturn, and other planets that are believed to have formed from smaller, circumplanetary ***ogs of the protoplanetary discs as well. According to the researchers team of the HST it is relatively rare to see visible images of proplyds, but the high resolution and sensitivity of the HST plus the Orion Nebula's proximity to Earth allowed them to obtain precise views of these potential planetary systems. CREDITS: NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA), the Hubble Space Telescope Orion Treasury Project Team and L. Ricci (ESO); all images released by Hubble / ESA under an Attribution-Unported 3.0 Creative Commons License. Music composed and interpreted by MANU CORNET, from his album "Distance Temps", song's name: "Distance", released by its author under an Attribution, Non-commercial, Share-alike, 3.0 Creative Commons License.
  • Hovindism #1 the definition of evolution (part 2/2) Kent completely destroys his version of the theory of evolution. References 1. Merriam-Webster. 2004. The Merriam-Webster Dictionary. Merriiam-Webster. 2. Weinberg, S. 2008. Cosmology. Oxford University Press. 3. Hubble, E. 1929. A relation between distance and radial velocity among extra galactic nebulae. PNAS 15(3):168-173. 4. Fixsen DJ, Cheng ES, Gales JM, Mather JC, ShaFer RA, Wright EL. 1996. The Cosmic Microwave Background Spectrum from the Full Cobe1 Firas Data Set. Astrophysical Journal 473:576-587. 5. Reeves H. 1974. On the origin of the light elements. Annuak Review of Astronomy and Astrophysics 12:437-470. 6. The Supernova Cosmology Project. 2003. New Constraints on [..], and w from an Independent Set of 11 High-Redshift Supernovae Observed with the Hubble Space Telescope. Astrophysical Journal. 598:102-137. 7. Kuo HM, Goldhaber G, Perlmutter S. 1998. A study of 42 type Ia supernovae and a resulting measurement of... Physics Reports 307(1):325-331. 8. Ellis GFR. 1979. The homogeneity of the universe. General Relativity and Gravitation 11(4):281-289. 9. Misner CW. 1968. The isotropy of the universe. Astrophysical Journal 151:431-457. 10. Hoyle F. 1946. The synthesis of the elements from hydrogen. Monthly Notices of the Royal Astronomical Society 106:343-383. 11. Seeger PA, Fowler WA, Clayton DD. 1965. Nucleosynthesis of heavy elements by neutron capture. Astrophysical Journal Supplement 11:121-166. 12. Bonnell IA, Bate MR. 2006. Star formation through ...
  • Order from Chaos: The Birth of the Solar System The solar system formed from a cloud of interstellar gas and dust cloud about 4.6 billion years ago. Life began on earth about 3.5 billion years ago following a period of intense bombardment by asteroid fragments and comets, intense volcanism and finally development of a stable crust and a hospitable atmosphere. Thanks to more powerful telescopes and other state-of-the-art observational methods, we can now see "stellar nurseries" and young stars at various stages of formation. In this talk well learn what triggers star formation in clouds, circumstellar disks and planet formation within the disks, and well discuss early life on earth. Series: Science on Saturday [2/2010] [Science] [Show ID: 17644]
  • Other Worlds - We are not alone. *** I made this short video because I was bored *** Confirmed Discoveries. The first published discovery to have received subsequent confirmation was made in 1988 by the Canadian astronomers Bruce Campbell, GAH Walker, and S. Yang. Their radial-velocity observations suggested that a planet orbited the star Gamma Cephei. They remained cautious about claiming a true planetary detection, and widespread skepticism persisted in the astronomical community for several years about this and other similar observations. It was mainly because the observations were at the very limits of instrumental capabilities at the time. Another source of confusion was that some of the possible planets might instead have been brown dwarfs, objects that are intermediate in mass between planets and stars. The following year, additional observations were published that supported the reality of the planet orbiting Gamma Cephei, though subsequent work in 1992 raised serious doubts. Finally, in 2003, improved techniques allowed the planet's existence to be confirmed. In early 1992, radio astronomers Aleksander Wolszczan and Dale Frail announced the discovery of planets around another pulsar, PSR 1257+12. This discovery was quickly confirmed, and is generally considered to be the first definitive detection of exoplanets. These pulsar planets are believed to have formed from the unusual remnants of the supernova that produced the pulsar, in a second round of planet formation, or else to be the remaining ...
  • The Hunt for the Planet Orbiting Beta Pictoris The nearby (63 LY) A5V -type star β Pictoris has been the subject of much scrutiny since the discovery of a planet-forming disk in the early 80's. In 2008, it was announced that a candidate planet had been detected by the European Southern Observatory in Chile. Faring on the side of caution, confirmation was required to rule out a background star. On June 10, 2010, the ESO announced that it had re-detected the companion, and that its motion through space showed it was very much bound to the star. Furthermore, with it now on the other side of the star, orbital motion is detected for the planet. β Pictoris b is a ~8 ± 2 Jupiter-mass companion in an 8 - 15 AU orbit around a young, 12 Myr old star. The discovery of β Pictoris b is direct evidence that massive planets can form quickly in a circumstellar disk. Its location in the system is also in agreement with having been formed through core accretion. β Pictoris b both confirms and constraints core-accretion based planet formation models, and will be an important target for future science. But the story is not over yet. β Pictoris b cannot explain all the disk structures, other playets may yet exist in the system. The planet's orbit will also become more constrained as observations continue. β Pictoris b joins a list of about 10 other planets that have been directly imaged, but so far all the other planets are much farther from their star and are likely to have formed by gravitational collapse of a massive, unstable ...
  • Evolution: A Witches Brew Joe Mastropaolo: "Unlike the accusing evolutionists, my work has been peer reviewed: 22 science articles in peer reviewed science journals. As a senior author, Richard Dawkins does not have even one. My 2002 article proved that all ape-men are frauds and caused the evolutionists to switch from evolution to devolution, a prime example that they don't know whether they are coming or going." Genesis 1:20 "And God said, Let the waters bring forth abundantly the moving creature that hath life, and fowl that may fly above the earth in the open firmament of heaven." Deep beneath the waves of many of our oceans, superheated water gushes from the ocean floor. The water is so loaded with minerals, especially with black iron sulfide, that it looks like black smoke. As the hot, mineral-rich water encounters the colder ocean water, some of the minerals precipitate, forming a black chimney around the escaping water. These chimneys are literally honeycombed with hollow compartments. Evolutionary scientists have proposed that these hollow compartments provided a kind of nursery shelter for the first life forms forming from the exotic chemistry of the hot mineral water. They know that living cell walls have an extremely complex structure, and this proposal is thought to solve the problem of the first life forming without its own cell walls. Some research has shown that iron sulfide may be able to support some of the chemistry related to life. However, one must assume that the right mix of ...
  • Protoplanetary Disk www.ralf- The dust disk of our emerging solar system, the protoplanetary disk. It was a rotating circumstellar disk of gas and dust surrounding the newly formed sun, 4.6 billion years ago! Digital, PhotoshopCS, Lighwave3D. Dimension 10000 x 7500 px, 300 dpi. Find the painting on my weblog! Protoplanetary disk: www.ralf- Music: "Das Observatorium" by Stephen Parsick from his CD "Höllenengel". With friendly permission by Stephen Parsik. Listen to his music on Musiczeit: Copyright by Ralf Schoofs and Stephen Parsick !
  • Massive pre-stellar core collapse (3D) The movie is based on data of a high-resolution radiation hydrodynamics simulation of the collapse of a pre-stellar core of cold gas and dust of 120 solar masses. The movie shows a zoom in on the center of the core, where after the initial free-fall epoch an accretion disk is formed around the central star (which is hidden in the inner sink cell). At roughly 8 kyr after the beginning of the collapse, the circumstellar accretion disk becomes unstable due its own gravity and evolves non-axially symmetric modes. This close-in gravitational instability in the disk drives an angular momentum transport outwards, allowing further mass transport inwards. The resulting accretion rate onto the massive star in the center is similar than in the previous two-dimensional simulations in axial symmetry, where we applied a shear-viscosity model to mimic the effect of angular momentum loss. Due to the high computational costs of this frequency-dependent three-dimensional radiation hydrodynamics simulations, the computation cannot run until the star has grown to its final mass (as it was done in the 2D case). For more details and scientific background, please visit: www.mpia-
  • Debris Disk Outside a Planetary System, animation of This animation shows the evolution of a planet-forming disc around a star. Initially, the young disc is bright and thick with dust, providing raw materials for building planets. In the first 10 million years or so, gaps appear within the disc as newborn planets coalesce out of the dust, clearing out a path. In time, this planetary "debris disc" thins out as gravitational interactions with numerous planets slowly sweep away the dust. Steady pressure from the starlight and solar winds also blows out the dust. After a few billion years, only a thin ring remains in the outermost reaches of the system, a faint echo of the once-brilliant disc. Our own solar system has a similar debris disc -- a ring of comets called the Kuiper Belt. Leftover dust in the inner portion of the solar system is known as "zodiacal dust." Bright, young discs can be imaged directly by visible-light telescopes, such as NASA's Hubble Space Telescope. Older, fainter debris discs can be detected only by infrared telescopes like NASA's Spitzer Space Telescope, which sense the discs' dim heat.
  • Touring the Physics of Fomalhaut b and the Belt (2009) Fomalhaut b is the first extrasolar planet to be directly imaged at visible wavelengths and to have its orbital motion around its host star measured (Kalas et al. 2008). The Fomalhaut system might also present the first example of planet-disk interaction during a formative era. This interaction is the subject of the animation. Over hundreds of millions of years, Fomalhaut b gravitationally ejects bodies from its immediate vicinity. It scours its so-called chaotic zone (Quillen 2006). The chaotic zone is a swath of space, enclosing the planet's orbit, that is purged of material because of dynamical instabilities (Wisdom 1980). In clearing its chaotic zone, Fomalhaut b erodes the circumstellar belt and carves out its inner edge. This erosion can be seen in the animation. The realization that the belt edge is located at the periphery of the planet's chaotic zone led Quillen (2006) to predict that a planet would be found orbiting just interior to the belt, with an orbital semimajor axis of 119 AU. This prediction appears vindicated by the discovery of Fomalhaut b, which indeed was found close to the belt edge. Previous Hubble Space Telescope observations revealed that the belt is elliptical (Kalas et al. 2005). The intrinsic ellipticity led to expectations that a planet was responsible (Wyatt et al. 1999). Planets on elliptical orbits imprint their ellipticities onto surrounding belt material. If Fomalhaut b were the only planet in the system, we would expect its orbit to be ...
  • New Planetary Systems In The Orion Nebula Science & Reason on Facebook: Hubblecast 32: Born in Beauty - Proplyds in the Orion Nebula. Visible to the *** eye, only 1500 light-years from Earth, the great Orion Nebula has been known and revered since ancient times. A popular target of Hubble, researchers have now identified 42 new discs within it that could be the beginnings of new planetary systems like our own. --- Please subscribe to Science & Reason: • • • • --- 14-Dec-2009: A collection of 30 never-before-released images of embryonic planetary systems in the Orion Nebula are the highlight of the longest single Hubble Space Telescope project ever dedicated to the topic of star and planet formation. Also known as proplyds, or protoplanetary discs, these modest blobs surrounding baby stars are shedding light on the mechanism behind planet formation. Only the NASA/ESA Hubble Space Telescope, with its high resolution and sensitivity, can take such detailed pictures of circumstellar discs at optical wavelengths. Looking like a graceful watercolour painting, the Orion Nebula is one of the most photogenic objects in space and one of the Hubble Space Telescope's favourite targets. As newborn stars emerge from the nebula's mixture of gas and dust, protoplanetary discs, also known as proplyds, form around them: the centre of the spinning disc heats up and becomes a new star, but remnants around the outskirts of the disc attract other bits of ...
  • Forming A Planetary Gap In A Circumstellar Disk Astronomers are using NASA's Spitzer Space Telescope to probe the structures of circumstellar discs, the dusty discs that surround young stars, to look for the earliest signs of the formation of planetary systems. Examining young stars in the constellation of Taurus known to have such discs, Spitzer's ultra-sensitive infrared spectrograph instrument has detected the clearest evidence to date that an inner gap has formed in the disc surrounding the star CoKu Tau 4. Such a gap could indicate the presence of a new planet that has formed from the missing material. This animation illustrates one possible scenario for the formation of an inner gap. Initially we see the circumstellar disc around a young star, made of the dust, ices and gases from which planets might form. As we move in to view the inner disc, an unstable ripple forms in the inner part of the disc. The force of gravity acts upon this ripple, allowing the material to rapidly condense into a new planet. The innermost portions of the disc that did not condense onto the planet rapidly spiral in and accrete onto the star, adding a little more to its final mass. Credit: NASA/JPL-Caltech/R. Hurt (SSC-Caltech)
  • Order from Chaos- The Birth of the Solar System The solar system formed from a cloud of interstellar gas and dust cloud about 4.6 billion years ago. Life began on earth about 3.5 billion years ago following a period of intense bombardment by asteroid fragments and comets, intense volcanism and finally development of a stable crust and a hospitable atmosphere. Thanks to more powerful telescopes and other state-of-the-art observational methods, we can now see "stellar nurseries" and young stars at various stages of formation. In this talk well learn what triggers star formation in clouds, circumstellar disks and planet formation within the disks, and well discuss early life on earth. Series: Science on Saturday [2/2010] [Science] [Show ID: 17644] Original video here : LICENCE: Creative Commons (Attribution-Noncommercial-No Derivative Works). For more information about this licence, please read:

Blogs & Forum
blogs and forums about circumstellar

  • “ has long been known to be surrounded by a circumstellar dust disk extending several hundred AU from the star. of rapid gas accretion before the loss of circumstellar gas – is the critical step in forming giant planets”
    — New Planet β Pictoris b Discovered,

  • “Archives of chemistry blog from networlddirectory, the place for information "The circumstellar environment is where chemistry happens for the very first time," said Lodders”
    — Archives of chemistry blog from NetWorlddirectory,

  • “Type A Stars with Circumstellar Dust Discovered. January 8th, 2009 characteristics of being accompanied by circumstellar dust, indicative of a young star”
    — Type A Stars with Circumstellar Dust Discovered, astrocast.tv

  • “Active stars Astrosphere Chromospheres Circumstellar disks Climate Cool stars Cosmogenic Tags: Active stars, Circumstellar disks, Climate, Cool stars, Dynamo, High-energy”
    — Living Reviews in Solar Physics – Blog " Circumstellar disks,

  • “more imagesWASHINGTON - A team of astronomers has captured the first direct, well-resolved infrared images of a circumstellar disk around a young massive star called HD 200775, to illuminate a massive star formation process”
    — Infrared image of circumstellar disk illuminates massive star,

  • “Both stars accrete from the circumstellar material, resulting in large photospheric Mg dwarf photospheres demonstrates that the circumstellar material is depleted in volatile”
    — White dwarf planets - Astronomy News,

  • “Read feedbacks by Revelation of noise on MySpace Blogs! New blogTopics added every minute. .Dave Clarke about Pulsar (original mix)Scary”
    — feedbacks - Revelation of noise's MySpace Blog |,

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