Geometry.Net - Science: Interstellar Medium

X-Ray Astronomy II: Interstellar Medium
Astrophysik. Abteilung Astronomie. Sand 1, D72076 Tübingen, Germany,Uni logo. Lecture on X-Ray Astronomy II. Chapter interstellar medium.
http://astro.uni-tuebingen.de/~wilms/teach/xray2/xray2chap5toc.html
Joseph Lazio: Turbulence In The Interstellar Medium
Turbulence in the interstellar medium. Note I've attempted to write thisdocument at an intermediate level. Turbulence in the interstellar medium.
http://rsd-www.nrl.navy.mil/7213/lazio/turbulence.html

Extractions: [Note: I've attempted to write this document at an intermediate level. It is not, I hope, at the level of a technical journal article. However, one may need to know a few basic astronomy facts to understand it completely.] The space between the stars is not empty. Rather it is filled with a gas of varying density and temperature. By terrestrial standards this interstellar medium (ISM) is a vacuum. By Galactic standards, the ISM is vitally important as it is the raw material from which stars are formed. Some of the ISM is ionized or in plasma form (i.e., the gas is hot enough that the electrons are stripped from the atoms, like the gas in the tubes of a neon sign). Presumably this plasma is formed by massive amounts of energy being injected into the ISM, for instance by the winds produced by the hottest stars, O and B stars, and near supernovae (the explosions which occur when O and B stars run out of fuel and collapse). By studying how stars interact with the ISM, we may gain a better understanding of how they are formed and how they die. Furthermore, radio astronomical observations must be conducted while looking through this plasma, so we must understand how it can affect our observations. Scintillation ( intensity fluctuations ) results from the passage of a light wave through a random medium (i.e., one in which the refractive index varies randomly). A common example of scintillation is the twinkling of starlight, resulting from visible light passing through the Earth's atmosphere. The Earth's atmosphere is a random medium because weather systems keep it "stirred up"; a typical scale on which the atmosphere varies is a few to 10 cm. Other common random media include the air over hot pavement and the exhaust of a jet airliner.
The Interstellar Medium At Wisconsin
*, The interstellar medium. An active program of research into the compositionof the interstellar medium exists at the UWMadison Physics department.
http://wisp5.physics.wisc.edu/ism/ism.html
Life In The Universe > Interstellar Medium/Clouds
interstellar medium/Clouds. Molecules in Interstellar Space The Life Cycleof Organic Matter (More material will be added soon!). Mayy 1, 2001.
http://www.lifeinuniverse.org/noflash/ism.html
The Interstellar Medium
The interstellar medium. COBE found the CII 158 m line to be the dominantcooling mechanism of the interstellar medium (Wright et al.
http://soral.as.arizona.edu/sofia2/node2.html

Extractions: Next: Protostellar Collapse and Disk Up: Scientific Motivation Previous: Scientific Motivation The proposed system will be capable of performing high spectral resolution studies of a number of important atomic and molecular species, including [SiI], [OI], [CII], CO, CH, OH, and [NII]. Of particular interest are the [CII] 158 m and [NII] 205 m lines, and a variety of lines from simple hydrides such as OH, CH, and CH COBE found the [CII] 158 m line to be the dominant cooling mechanism of the interstellar medium (Wright et al. 1991; Bennet et al. et al. 1993; Stutzki et al. et al. times more sensitive per pixel and have 16 times the spatial coverage of earlier heterodyne instruments flown on the KAO. The potential power of STAR in probing conditions in and around molecular clouds is illustrated in Figure 1. In the middle of the figure we show an image of NGC 6334 made in CO J=4 from AST/RO with a receiver system constructed in the PI's lab. The small square of emission in the top right hand corner is the size of the region that could be mapped in CII at full beam spacings with a single receiver channel in one flight ( hrs). The second square shows the region that could be mapped with STAR in the same period of time, essentially the whole cloud. The CII spectra at the bottom left were taken by Borieko and Betz (1995). The width and complexity of the line profiles are well matched to the 40 km/s velocity coverage and 0.125 km/s velocity resolution available in each STAR pixel.
Keyword Index Listing For I
Infrared stars,, Interferometry,, interstellar medium,, interstellar medium molecularclouds, H II regions, individual objects IC 1396, kinematics and dynamics
http://xml.gsfc.nasa.gov/archive/KeywordIndexI.html

Extractions: Keywords for letter I: Keyword Associated Datasets IRAS sources IRAS sources beyond the solar circle. I. CO observations (Wouterloot, J.G.A.+,1989) ISM Star formation in L1251: distance and members (Kun, M.+,1993) ISM: Chamaeleon clouds A study of the Chamaeleon star forming region from the ROSAT all-sky survey. I. X-ray observations and optical identifications (Alcala, J.M.+,1995) ISM: H I bubbles The Seventh Catalogue of Galactic Wolf-Rayet stars (Hucht, K.A.,2001) ISM: H II regions The Seventh Catalogue of Galactic Wolf-Rayet stars (Hucht, K.A.,2001) ISM: H II regions: planetary nebulae Iron Project. XLIV. Transition probabilities and line ratios for Fe VI with fluorescent excitation in planetary nebulae (Chen, G.-X.+,2000) ISM: HII regions Environment dependence of interstellar extinction curves (Jenniskens, P.+,1993) A survey of water maser emission toward ultracompact HII regions (Hofner, P.+,1996) A survey of molecular line emission towards ultracompact HII regions (Hatchell, J.+,1998) ISM: Lupus clouds New "weak-line" T Tauri stars in Lupus (Krautter, J.+,1997)
APOD: 2002 February 10 - The Local Interstellar Cloud
In the disk of our Milky Way Galaxy about 10 percent of visible matteris in the form of gas, called the interstellar medium (ISM).
http://antwrp.gsfc.nasa.gov/apod/ap020210.html

Extractions: Linda Huff ( American Scientist Priscilla Frisch U. Chicago Explanation: The stars are not alone. In the disk of our Milky Way Galaxy about 10 percent of visible matter is in the form of gas, called the interstellar medium (ISM). The ISM is not uniform, and shows patchiness even near our Sun . It can be quite difficult to detect the local ISM because it is so tenuous and emits so little light. This mostly hydrogen gas, however, absorbs some very specific colors that can be detected in the light of the nearest stars . A working map of the local ISM within 10 light-years based on recent observations is shown above . These observations show that our Sun is moving through a Local Interstellar Cloud as this cloud flows outwards from the Scorpius-Centaurus Association star forming region. Our Sun may exit the Local Interstellar Cloud during the next 10,000 years. Much remains unknown about the local
APOD: December 18, 1996 - A Sky Full Of Hydrogen
It is a rare event for Hydrogen atoms in the interstellar medium to switch fromthe parallel to the antiparallel configuration, but when they do they emit
http://antwrp.gsfc.nasa.gov/apod/ap961218.html

Extractions: Credit: J. Dickey ( UMn ), F. Lockman ( NRAO SkyView Explanation : Interstellar space is filled with extremely tenuous clouds of gas which are mostly Hydrogen. The neutral hydrogen atom (HI in astronomer's shorthand) consists of 1 proton and 1 electron. The proton and electron spin like tops but can have only two orientations; spin axes parallel or anti-parallel. It is a rare event for Hydrogen atoms in the interstellar medium to switch from the parallel to the anti-parallel configuration, but when they do they emit radio waves with a wavelength of 21 centimeters (about 8 inches) and a corresponding frequency of exactly 1420 MHz. Tuned to this frequency radio telescopes have mapped the neutral Hydrogen in the sky. The above image represents such an all-sky HI survey with the plane of our Milky Way Galaxy running horizontally through the center. In this false color image no
Interstellar Medium -- From Eric Weisstein's World Of Astronomy
interstellar medium, Dordrecht, Netherlands Reidel, 1985. Dyson, J. E. and Williams,D. A. Physics of the interstellar medium. New York Wiley, 1980.
http://scienceworld.wolfram.com/astronomy/InterstellarMedium.html

Extractions: References Aller, L. H. Physics of Thermal Gaseous Nebulae: Physical Processes in Gaseous Nebulae. Dordrecht, Netherlands: Reidel, 1984. Andrew, B. H. (Ed.). Interstellar Molecules: Symposium No. 87, Held at Mont Tremblant, Quebec, Canada, August 6-10, 1979. Dordrecht, Netherlands: Reidel, 1980. Balian, R.; Encrenaz, P.; and Lequeux, J. (Eds.). Atomic and Molecular Physics and the Interstellar Matter: Les Houches, Session XXVI, 1 juillet-23 aout 1974. Amsterdam, Netherlands: North-Holland, 1975. Bowers, R. L. and Deeming, T. Astrophysics, Vol. 2: Interstellar Matter and Galaxies. Boston: Jones and Bartlett Publishers, 1984. Cowen, R. "Heavy Elements Found in Interstellar Gas." Sci. News Diercksen, G. H. F.; Huebner, W. F.; and Langhoff, P. W. (Eds.). Molecular Astrophysics: State of the Art and Future Directions. Dordrecht, Netherlands: Reidel, 1985. Dyson, J. E. and Williams, D. A.
Interstellar Medium (ISM)
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z interstellar medium (ISM)
http://www.angelfire.com/on2/daviddarling/ISM.htm

Extractions: The material that exists between the stars which, in our own Galaxy, consists of about 99% gas and 1% cosmic dust grains. It is strongly concentrated in the galactic disk , with an average density of about one particle per cubic centimeter but a much greater local density, of 10 billion particles per cubic centimeter, in pre-stellar clouds known as globules . The gas of the ISM is mostly hydrogen in an ionized, neutral, or molecular (see molecular clouds ) state. However, in the formation of terrestrial planets and the evolution of life, the presence of small quantities of heavy elements , such as carbon and oxygen, is crucial. These elements were formed in the cores of earlier generations of stars and have recycled through the ISM to become the raw material from which new stars and their retinues of worlds are formed.
Session 47. The Interstellar Medium I
meeting. Session 47. The interstellar medium I. Poster, Tuesday, January7, 2003, 920am630pm, Exhibit Hall AB. 47.01 Statistics
http://www.aas.org/publications/baas/v34n4/aas201/S470.htm

Extractions: All findings are embargoed until the time of presentation at the meeting. Statistics of Galactic Cosmic Ray Modulation Variations Using Simulations of the Turbulent Interstellar Medium J. Scalo, D. Smith (UT Austin), E. Vazquez-Semadeni (UNAM, Mexico) Properties of Interstellar Turbulence and its Implications A. Lazarian, J. Cho, A. Esquivel, H. Yan (UW-Madison) Probing the Diffuse Interstellar Medium at AU Scales J. T. Lauroesch, D. M. Meyer (Northwestern Univ.) The metal abundance in the interstellar medium from X-ray grating spectroscopy of AGN E. Lloyd-Davies, J. Bregman (University of Michigan) W.T. Sanders, D. Lieu, D. McCammon, L. Rocks, J.E. Vaillancourt (University of Wisconsin-Madison), M. Galeazzi (University of Miami), E. Figueroa-Feliciano, R.L. Kelley, R.F. Mushotzky, F.S. Porter, C.K. Stahle (NASA-Goddard Space Flight Center), A.E. Szymkowiak (Yale University) HST Archival Imaging of the Light Echoes of SN 1987A S. S. Lawrence, M. Hayon (Hofstra U.), B. E. K. Sugerman, A. P. S. Crotts (Columbia U.)
Session 77. The Interstellar Medium II
the meeting. Session 77. The interstellar medium II. Poster, Wednesday,January 8, 2003, 920am630pm, Exhibit Hall AB. 77.01 FUSE
http://www.aas.org/publications/baas/v34n4/aas201/S770.htm

Extractions: All findings are embargoed until the time of presentation at the meeting. FUSE, HST, and Chandra Spectra of the Interstellar Gas and Dust toward X Persei T. P. Snow, N. J. Cunningham, M. M. Drosback (CASA, University of Colorado), R. A. McCray (JILA, University of Colorado), B. L. Rachford (CASA, University of Colorado) FUSE Observations of Rotationally Excited H in Translucent Lines of Sight B. L. Rachford, E.J. Baker, T.P. Snow (CASA/CU) J. Zsargo (JHU), K.R. Sembach (STScI), J.C. Howk (CASS, UCSD), B.D. Savage (U. Wisconsin) Deuterium, Nitrogen, and Oxygen abundances toward WD0004+330: Results from the FUSE mission. C. M. Oliveira (JHU), G. Hebrard (Inst. d'Astrophysique de Paris), S. D. Friedman (STScI), H. W. Moos (JHU) S.D. Points, D.M. Meyer, J.T. Lauroesch, D.T. Nguyen (Northwestern U.), S.D. Friedman (STScI) The Search for O with the Odin Satellite M. Fich, C.L. Curry (University of Waterloo), L. Pagani (Observatoire de Paris), ODIN Team
Interstellar Medium.
next up previous Next Molecular Clouds and Star Up Beyond the Solar SystemPrevious Galactic Plane Continuum Surveys. interstellar medium.
http://www.narrabri.atnf.csiro.au/~jhouldsw/c40report/node44.html

Extractions: Next: Molecular Clouds and Star Up: Beyond the Solar System Previous: Galactic Plane Continuum Surveys The NRAO 140-ft telescope has been used to detect distinct HI clouds towards X-ray shadows, regions where ROSAT results indicate that soft X-rays appear to be absorbed by intervening interstellar matter. Results in the Eridanus region indicate that most of the absorption occurs at a distance of about 100 pc, which is consistent with the model in which most of the soft X-ray background originates in a hot bubble of gas surrounding the Sun. The NRAO 140-ft telescope has been used in a sensitive search for high-velocity HI clouds near and along line-of-sight to QSOs. About 37% of the observed directions contained high-velocity gas at velocities greater than 100 km s. In NRAO 12-m telescope observations probing the ISM, CO J=1-0 absorption has been detected towards some compact extragalactic mm-wave continuum sources. Similar observations have been made with the IRAM interferometer for HCO J=1-0 absorption; the absorption was found to be surprisingly common, occurring in 30% as often as HI absorption for the same directions.
3rd Cologne-Zermatt Symposium
3rd CologneZermatt Symposium The Physics andChemistry of the interstellar medium.
http://www.ph1.uni-koeln.de/zermatt1998/

Extractions: The Physics and Chemistry of the Interstellar Medium was held in Zermatt, September 22nd - 25th, 1998 The conference focused on the structure and processes in molecular clouds and the general interstellar medium ranging from star formation in the early universe to the analysis of the composition of the interstellar matter in our neighborhood. The complete conference program and abstracts of all contributions are available from the online abstract book With 193 participants from allover the globe, 9 reviews, 19 invited talks, 29 contributed talks, and 134 posters on a high scientific level the meeting was a success for all participants. We want to thank the scientific organizing comittee , the local organizing comittee , and all people who helped to make the conference that success. We have printed posters which were sent to many different institutes to announce the conference. If you would like to get an additional
Interstellar Medium And Star Formation
Research Activities interstellar medium and Star Formation. The generalgoals of the research group can be formulated as follows To
http://www.astro.helsinki.fi/report/1998/node11.html

Extractions: Next: Infrared studies with ISO: Up: Research Activities Previous: Research Activities The general goals of the research group can be formulated as follows: To investigate the physical and chemical propetrties of interstellar molecular clouds, especially the initial conditions for star formation , i.e. the temperature, density, radiation field and chemical composition. The radio spectroscopical studies performed by the group have been directed towards the following three main fields: 1) Dynamical processes and chemistry in nearby low-mass star forming regions These three lines of investigation are interrelated and are instrumental to the understanding of the evolution of molecular clouds and the star formation process in general. To investigate the properties and composition of interstellar dust grains in dense and diffuse clouds, especially by means of the infrared emission and scattered radiation.
Research Of Interstellar Medium And Star Formation
Research of interstellar medium and star formation. Project number, 81525002.Research agreements, Academy of Finland. Type of research, Basic research.
http://www.astro.helsinki.fi/report/2000/node3.html

Extractions: Next: Research activities Up: Title Page Previous: Strategy of the Observatory Project number Research agreements Academy of Finland Type of research Basic research Director of research Prof. Mattila, Kalevi Telephone Fax E-mail Kalevi.Mattila@Helsinki.Fi Research staff with a Ph.D. Kalevi Mattila, Prof Jorma Harju, Docent Mika Juvela, Docent Kimmo Lehtinen, Ph.D. Mark Rawlings, Ph.D. Delphine Russeil, Ph.D. Ph.D. student(s) Samu Kontinen, M.Sc. Asko Palviainen, M.Sc. M.Sc. student(s) Peter Johansson Cajus Pomren Associated research staff Lauri Haikala, Docent Technical staff Mikko Toriseva, Lic. Tech.
Thermal Phases Of The Interstellar Medium In Galaxies - M.C. Begelman
Published in The interstellar medium in Galaxies , eds. HA Thronson, Jr. THERMALPHASES OF THE interstellar medium IN GALAXIES. Mitchell C. Begelman.
http://nedwww.ipac.caltech.edu/level5/March02/Begelman/Begel_contents.html

Extractions: Abstract. This review deals with the theory of multiphase media in astrophysical systems. I discuss the basic reasons for the existence of multiple thermal phases, and the fundamental connection between multiphase media and thermal instability. After describing important examples of multiphase media, I examine the interactions among phases, i.e., mass exchange driven by thermal conduction and hydrodynamic ablation. Mass exchange may compete with radiative heating and cooling for control of the thermal state of the hot phase, and may alter the thermal stability properties of the system.
The Cool Phase Of The Interstellar Medium: Atomic Gas - E. Brinks
Braun, R., and Walterbos, RAM 1989, in The interstellar medium in External Galaxies,(Poster Session), eds. DJ Hollenbach and HA Thronson, Jr., NASA Conf.
http://nedwww.ipac.caltech.edu/level5/March01/Brinks/Brinks_refs.html

Extractions: Abbott, D. C. Ap. J. Ap. J. Suppl. Bottema, R., Shostak, G. S, and van der Kruit, P. C. Astr. Ap. Astr. Ap. Braun, R. 1989, Ap. J. Suppl. , submitted. Braun, R., and Walterbos, R. A. M. 1989, in The Interstellar Medium in External Galaxies, (Poster Session) , eds. D. J. Hollenbach and H. A. Thronson, Jr., NASA Conf. Proc. , (Washington: NASA), in press Bregman, J. N. Ap. J. Brinks, E., and Bajaja, E. Astr. Ap. Brinks, E., Braun, R., and Unger, S. W. 1989 in IAU Colloquium 120, Structure and Dynamics of the Interstellar Medium , eds. G. Tenorio-Tagle, M. Moles, and J. Melnick, Lecture Notes in Physics , (New York: Springer-Verlag) p. 524. Brinks, E., and Burton, W. B. Astr. Ap. Brinks, E., and Shane, W. W. Astr. Ap. Suppl. Clark, B. G. Ap. J. Cohen, R. S., Dame, T. M., Garay, G., Montani, J., Rubio, M., and Thaddeus, P. Ap. J. (Letters) Corbelli, E., and Salpeter, E. E. Ap. J. Corbelli, E., and Salpeter, E. E. 1990, in The Interstellar Medium in External Galaxies, (Poster Session) , eds. D. J. Hollenbach and H. A. Thronson, Jr., NASA Conf. Proc.
KLUWER Academic Publishers | The Heliosphere In The Local Interstellar Medium
Books » The Heliosphere in the Local interstellar medium. The Heliospherein the Local interstellar medium. Add to cart. edited by
http://www.wkap.nl/prod/b/0-7923-4320-4

Extractions: This volume gives a comprehensive and integrated overview of current knowledge about the local interstellar medium (LISM) surrounding our heliosphere (HS). It is the result of the first workshop at ISSI, where both space physicists and astronomers presented and discussed their views on the density, velocity, temperature, composition, and morphology of the LISM and how it interacts with the HS. The volume is unique in its combination of data obtained by remote UV, EUV, and X-ray observations outside the HS with in situ observations of interstellar atoms, ions, and dust inside the HS. It thus demonstrates a new synergy between these two communities. The book is intended to provide active researchers in space physics and in astronomy with an up-to-date status report of its topic, and also to furnish the advanced graduate student with introductory material into the field. Kluwer Academic Publishers, Dordrecht
KLUWER Academic Publishers | The Interstellar Medium In Galaxies
Books » The interstellar medium in Galaxies. The interstellar mediumin Galaxies. Add to cart. edited by JM van der Hulst Kapteyn
http://www.wkap.nl/prod/b/0-7923-4676-9

Extractions: The Interstellar Medium in Galaxies is a collection of seven reviews covering the following constituents of the interstellar medium: dust, molecular gas, neutral atomic hydrogen, ionized hydrogen, and hot gas, and covering the abundances of heavy elements in the interstellar medium and the role of star formation. The reviews not only provide a good background in these subjects, but also describe in detail the most recent advances in the area and discuss the current problems in the field. The properties of the different constituents of the interstellar medium are discussed within the perspective of the difference in properties of the parent galaxies and the environment. The interplay between star formation and the characteristics of the interstellar medium is also discussed in detail. This volume provides very up-to-date material on the subject of the interstellar medium in galaxies and is useful both as a basic reference for professional scientists in this field and as an introductory book for astronomers who want to familiarize themselves with this field. This volume can also serve as an accompanying text book for graduate courses on the interstellar medium.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

41-60 of 98 Back | 1 | 2 | 3 | 4 | 5 | Next 20