Stellar Winds and Hydrodynamic Atmospheres
... the implicit solution Eq. 8b for v(r) together with the conditions for the critical point Eq. 7a,b can be used to discuss topology of solution families ...
... the implicit solution Eq. 8b for v(r) together with the conditions for the critical point Eq. 7a,b can be used to discuss topology of solution families ...
Mise en page 1
... light years away or a few thousand, but to us they appear dotted on a giant dome rotating above the Earth. Although we now know that it is the Earth that rotates, the illusion serves as a convenient model. Since the axis of the Earth’s rotation goes through the poles, a patient observer at the North ...
... light years away or a few thousand, but to us they appear dotted on a giant dome rotating above the Earth. Although we now know that it is the Earth that rotates, the illusion serves as a convenient model. Since the axis of the Earth’s rotation goes through the poles, a patient observer at the North ...
ppt - Astronomy & Physics
... Atmospheric CO2 rises as surface gets colder because weathering (a sink of CO2) stops and volcanic activity (a source of CO2) becomes more important ...
... Atmospheric CO2 rises as surface gets colder because weathering (a sink of CO2) stops and volcanic activity (a source of CO2) becomes more important ...
sections 7-8 instructor notes
... The primary opacity source in the atmospheres of B and A-type stars is atomic hydrogen, which makes its presence obvious in the flux distributions of such stars with discrete discontinuities in the stellar continua at λ912Å (the Lyman discontinuity), λ3647Å (the Balmer discontinuity), and λ8206Å (t ...
... The primary opacity source in the atmospheres of B and A-type stars is atomic hydrogen, which makes its presence obvious in the flux distributions of such stars with discrete discontinuities in the stellar continua at λ912Å (the Lyman discontinuity), λ3647Å (the Balmer discontinuity), and λ8206Å (t ...
t 0 (radioactive decay)
... unstable isotopes as a way to estimate the age of stars and the Milky Way Galaxy, and thus t0. Briefly, radioactive decay is the process by which “parent” isotopes spontaneously lose energy and turn into new “daughter” isotopes. The parent isotope’s half-life defines the rate at which this decay occ ...
... unstable isotopes as a way to estimate the age of stars and the Milky Way Galaxy, and thus t0. Briefly, radioactive decay is the process by which “parent” isotopes spontaneously lose energy and turn into new “daughter” isotopes. The parent isotope’s half-life defines the rate at which this decay occ ...
Supernova and Supernova Remnants lec 1-2
... • Sometimes the explosion does not seem to produce lots of hot gas and instead one detects synchrotron emission from relativistic particles produced by a central Neutron star – these are called plerions or 'Crab-like' SNR. – in 'thermal' remnants there can be synchrotron emission from shock accelera ...
... • Sometimes the explosion does not seem to produce lots of hot gas and instead one detects synchrotron emission from relativistic particles produced by a central Neutron star – these are called plerions or 'Crab-like' SNR. – in 'thermal' remnants there can be synchrotron emission from shock accelera ...
Basic Properties of Light
... • GMT - 7x8.4m=24.5m in Chile, CA, Harvard, Texas, Arizona, Chicago, Australia, Korea ...
... • GMT - 7x8.4m=24.5m in Chile, CA, Harvard, Texas, Arizona, Chicago, Australia, Korea ...
Asteroseismology of Solar-Like Stars
... (pressure) modes. In gravity modes the restoring force for the oscillation is the gradient of the gravitational acceleration within the star, they are also known as buoyancy waves. A parcel of gas within a star will rise if the material is less dense than of its surroundings. The g mode oscillations ...
... (pressure) modes. In gravity modes the restoring force for the oscillation is the gradient of the gravitational acceleration within the star, they are also known as buoyancy waves. A parcel of gas within a star will rise if the material is less dense than of its surroundings. The g mode oscillations ...
... CAIs are thought to be the first solid objects formed when the Solar System formed. Analysis of CAIs indicates that the ratio of aluminum-26 to the common, nonradioactive aluminum-27 was about 0.00005 when the objects formed. However, a few CAIs have much lower ratios, so low that they may not have ...
feb18_rg
... Since the galactic plane is thin, face-on galaxies seldom exhibit evidence for significant optical thickness: the vast majority of the atomic gas is in optically thin clouds. As disks approach the edge-on aspect, velocity spread to a large extent prevents optical depth to increase significantly. As ...
... Since the galactic plane is thin, face-on galaxies seldom exhibit evidence for significant optical thickness: the vast majority of the atomic gas is in optically thin clouds. As disks approach the edge-on aspect, velocity spread to a large extent prevents optical depth to increase significantly. As ...
File
... structures called filaments. These filaments are the largest known structures in the universe. ...
... structures called filaments. These filaments are the largest known structures in the universe. ...
Interpretation and prospects 21 cm Intensity mapping with the Green Bank Telescope:
... Foregrounds only smooth in Stokes I, if beam is smooth Polarization leakage mixes in Q, U Improve things by smoothing ...
... Foregrounds only smooth in Stokes I, if beam is smooth Polarization leakage mixes in Q, U Improve things by smoothing ...
cosmo_01_overview - Mullard Space Science Laboratory
... So the arms must be moving slower than the actual material! Best model is that they are density waves in the disc. Fast moving gas and dust arrives at a region of higher density. The gas is slowed and compressed causing star formation. Bright new stars move out of dense region and travel on. O and B ...
... So the arms must be moving slower than the actual material! Best model is that they are density waves in the disc. Fast moving gas and dust arrives at a region of higher density. The gas is slowed and compressed causing star formation. Bright new stars move out of dense region and travel on. O and B ...
Exoplanets - An ESO/OPTICON/IAU summer school on modern
... (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit." IAU, Resolution B5 "Extrasolar planet is: an object that has a mass between that of Pluto and the deu ...
... (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit." IAU, Resolution B5 "Extrasolar planet is: an object that has a mass between that of Pluto and the deu ...
ET_at_Science_Cafe
... when a signal is not `random’? • Information theory says maximally compact data is indistinguishable from noise! • ETI signal should have inexplicable regularities: repeated sequences, letters, frames, apparent structures…. (Applies to all SETI). • Who knows how they might encode? • Hopefully we wil ...
... when a signal is not `random’? • Information theory says maximally compact data is indistinguishable from noise! • ETI signal should have inexplicable regularities: repeated sequences, letters, frames, apparent structures…. (Applies to all SETI). • Who knows how they might encode? • Hopefully we wil ...
The VLA COSMOS Survey
... The VLA-COSMOS survey: Tracing star-forming and AGN galaxies through cosmic time Vernesa Smolčić (Caltech) E. Schinnerer (MPIA), C.L. Carilli (NRAO), M. Bondi (INAF), P. Cilliegi (INAF), G. Zamorani (INAF), K. Jahnke (MPIA), M. Sargent (MPIA) & the (VLA-)COSMOS collaboration ...
... The VLA-COSMOS survey: Tracing star-forming and AGN galaxies through cosmic time Vernesa Smolčić (Caltech) E. Schinnerer (MPIA), C.L. Carilli (NRAO), M. Bondi (INAF), P. Cilliegi (INAF), G. Zamorani (INAF), K. Jahnke (MPIA), M. Sargent (MPIA) & the (VLA-)COSMOS collaboration ...
Celestial Equator
... This probably does not indicate evolution at its center. 570 ly away. Variable star. 1000 times as luminous as the sun Rigel - brightest star in Orion by (a bit more than -Orionis = Betelgeuse – a variable) 7th brightest star in the sky. 770 ly. Most luminous star in our region of galaxy. A blue su ...
... This probably does not indicate evolution at its center. 570 ly away. Variable star. 1000 times as luminous as the sun Rigel - brightest star in Orion by (a bit more than -Orionis = Betelgeuse – a variable) 7th brightest star in the sky. 770 ly. Most luminous star in our region of galaxy. A blue su ...
Lecture 12
... 0.08 stars/pc3 observable near the Sun. – How many stars, in principle, exist that could have their distances measured by the parallax method? – If accuracy improved to 0.001 second of arc (with Hipparcos, for example), how many stars would have measurable parallaxes? ASTR111 Lecture 12 ...
... 0.08 stars/pc3 observable near the Sun. – How many stars, in principle, exist that could have their distances measured by the parallax method? – If accuracy improved to 0.001 second of arc (with Hipparcos, for example), how many stars would have measurable parallaxes? ASTR111 Lecture 12 ...
Article PDF - IOPscience
... components in this galaxy from the spectroscopy alone. The methodologically independent discovery of two distinct stellar components in CVn I from the LBC photometry and the much smaller extent of the young population surprisingly recalls their findings. A direct comparison of their spectroscopic sa ...
... components in this galaxy from the spectroscopy alone. The methodologically independent discovery of two distinct stellar components in CVn I from the LBC photometry and the much smaller extent of the young population surprisingly recalls their findings. A direct comparison of their spectroscopic sa ...
East Valley Astronomy Club
... New models of the “minimum mass solar nebula” show the nebula really was very dense, but this structure is only understood if the disk was photoevaporating because of a nearby massive star. Meteorites show the Solar System contained live 60Fe, almost certainly ejected by a nearby massive star that w ...
... New models of the “minimum mass solar nebula” show the nebula really was very dense, but this structure is only understood if the disk was photoevaporating because of a nearby massive star. Meteorites show the Solar System contained live 60Fe, almost certainly ejected by a nearby massive star that w ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.