![The Discovery of Quasars - CSIRO Parkes Observatory](http://s1.studyres.com/store/data/017070503_1-e628b32c6dcc81987ac250485edd85de-300x300.png)
The Discovery of Quasars - CSIRO Parkes Observatory
... 1963). Observations by Sandage at the 200 inch telescope showed that except for the faint “wisp” that most of the optical light was unresolved, that the color was “peculiar” and that the optical counterpart varied by at least 0.4 mag over a time scale of months, thus supporting the notion that 3C 48 ...
... 1963). Observations by Sandage at the 200 inch telescope showed that except for the faint “wisp” that most of the optical light was unresolved, that the color was “peculiar” and that the optical counterpart varied by at least 0.4 mag over a time scale of months, thus supporting the notion that 3C 48 ...
Dynamical Mass Measurements of Pre-Main
... instrumental angular resolution limits. As such, systematic errors in the calibration are an important challenge that may propagate into the masses via the inclination angle i. Looking to the very near future, new applications of the AS technique will rely in large part on interferometric data. The ...
... instrumental angular resolution limits. As such, systematic errors in the calibration are an important challenge that may propagate into the masses via the inclination angle i. Looking to the very near future, new applications of the AS technique will rely in large part on interferometric data. The ...
Radiative hydrodynamics simulations of red supergiant stars. III
... The top panel of Fig. 5 shows the temporal photocenter displacement over the ≈ 5 years of simulation, which is comparable to the total length of the Gaia mission. As seen in the Figure, for t < 22 yr, the random displacement is small and increases to a maximum value of 0.30 AU at t ∼ 23 yr. In relat ...
... The top panel of Fig. 5 shows the temporal photocenter displacement over the ≈ 5 years of simulation, which is comparable to the total length of the Gaia mission. As seen in the Figure, for t < 22 yr, the random displacement is small and increases to a maximum value of 0.30 AU at t ∼ 23 yr. In relat ...
The Mass-loss Rate of Red Supergiant
... balance between the grain heating through irradiation and cooling through reradiation. The optical depth of the dust envelope can be derived from the observed SED by comparison with synthetic SEDs. We can derive the radiation pressure applied on dust from the SEDs (Van Loon 2007, Ivezic et al. 1995) ...
... balance between the grain heating through irradiation and cooling through reradiation. The optical depth of the dust envelope can be derived from the observed SED by comparison with synthetic SEDs. We can derive the radiation pressure applied on dust from the SEDs (Van Loon 2007, Ivezic et al. 1995) ...
A photometrically and spectroscopically confirmed
... is calculated from the standard deviation of the subsequent Hα measurements. For four of the six galaxies, the measured value of any Hα is less than the estimated error in this measurement and we conclude their spectra are consistent with being passive. For the remaining two, IC 375 and CGCG 394−006 ...
... is calculated from the standard deviation of the subsequent Hα measurements. For four of the six galaxies, the measured value of any Hα is less than the estimated error in this measurement and we conclude their spectra are consistent with being passive. For the remaining two, IC 375 and CGCG 394−006 ...
The European Large Area ISO Survey – IV. The preliminary 90
... constant n Ln (for ease of conversion to other luminosity scales). Our method for calculating the luminosity function in the face of this complicated selection function is dealt with in the appendix. Note that our method relies on the underlying assumption that no galaxies are missing at all redshif ...
... constant n Ln (for ease of conversion to other luminosity scales). Our method for calculating the luminosity function in the face of this complicated selection function is dealt with in the appendix. Note that our method relies on the underlying assumption that no galaxies are missing at all redshif ...
The science case for - Astrophysics
... photons which re-ionised the Universe some 200million years after the Big Bang, and made it transparent? These objects may be visible through their supernovae, or their ionisation zones. How many types of matter exist? What is dark matter? Where is it? Most matter is transparent, and is detectable o ...
... photons which re-ionised the Universe some 200million years after the Big Bang, and made it transparent? These objects may be visible through their supernovae, or their ionisation zones. How many types of matter exist? What is dark matter? Where is it? Most matter is transparent, and is detectable o ...
Discovery of White Dwarfs—1 Oct • Adams’ discovery
... • How much smaller is Sirius B? • Apparent mag of Sirius A is −1.5 • Apparent mag of Sirius B is 8.7 ...
... • How much smaller is Sirius B? • Apparent mag of Sirius A is −1.5 • Apparent mag of Sirius B is 8.7 ...
Galaxy formation and evolution in the CDM model
... irradiation, (3) heating by the uniform cosmic UV background (important at z > 2, see Haardt & Madau 1998, 2001) (4) radiative/turbulent heating by supernovae explosions and supermassive black holes. (3)Angular momentum This depends on the initial angular momentum distribution of dark matter and bar ...
... irradiation, (3) heating by the uniform cosmic UV background (important at z > 2, see Haardt & Madau 1998, 2001) (4) radiative/turbulent heating by supernovae explosions and supermassive black holes. (3)Angular momentum This depends on the initial angular momentum distribution of dark matter and bar ...
The significant contribution of minor mergers to the cosmic star
... models and assuming a Kroupa (2001) initial mass function. Model likelihoods are calculated from the values of χ2 , and 1D probability distributions for free parameters like stellar mass are constructed via marginalisation. The median of the 1D distribution provides a best estimate for the parameter ...
... models and assuming a Kroupa (2001) initial mass function. Model likelihoods are calculated from the values of χ2 , and 1D probability distributions for free parameters like stellar mass are constructed via marginalisation. The median of the 1D distribution provides a best estimate for the parameter ...
Project Description - SDSS-III
... Universe imprint a characteristic scale on the clustering of dark matter, galaxies, and intergalactic gas. By measuring this scale with tracers seen at different redshifts, we can create a “Hubble diagram” of unprecedented precision covering most of cosmic history and can thereby pin down the prope ...
... Universe imprint a characteristic scale on the clustering of dark matter, galaxies, and intergalactic gas. By measuring this scale with tracers seen at different redshifts, we can create a “Hubble diagram” of unprecedented precision covering most of cosmic history and can thereby pin down the prope ...
The Kuiper Belt Explored by Serendipitous Stellar Occultations
... The characteristic scale of the Fresnel diffraction effect (i.e., roughly speaking, the broadening of the object shadow) is the so-called Fresnel scale Fs = (λD/2) (Warner, 1988). [Note that some authors give different definitions for the Fresnel scale: (λD/2π) , (λD) , or (λD)/2 .] The Fresnel scal ...
... The characteristic scale of the Fresnel diffraction effect (i.e., roughly speaking, the broadening of the object shadow) is the so-called Fresnel scale Fs = (λD/2) (Warner, 1988). [Note that some authors give different definitions for the Fresnel scale: (λD/2π) , (λD) , or (λD)/2 .] The Fresnel scal ...
Metal-poor Stars
... although more were predicted to exist by a simple model of chemical evolution in the Galactic halo. Bond (1981) reported on unsuccessful searches for these Population III stars and concluded that long-lived low-mass star could not easily form from zero-metallicity gas, and hence were extremely rare, ...
... although more were predicted to exist by a simple model of chemical evolution in the Galactic halo. Bond (1981) reported on unsuccessful searches for these Population III stars and concluded that long-lived low-mass star could not easily form from zero-metallicity gas, and hence were extremely rare, ...
Investigating Black Hole Kicks
... X-ray binaries, in particular, harbor a wealth of information on how black holes are formed. They allow us to measure natal kicks, i.e. the velocities that a compact object might receive at birth due to asymmetries in the supernova event. X-ray binaries containing a neutron star as the compact objec ...
... X-ray binaries, in particular, harbor a wealth of information on how black holes are formed. They allow us to measure natal kicks, i.e. the velocities that a compact object might receive at birth due to asymmetries in the supernova event. X-ray binaries containing a neutron star as the compact objec ...
Recent star formation in local, morphologically disturbed
... Universe and the (photometric) properties of the early-type population (e.g. Cole et al. 2000; Hatton et al. 2003; Kaviraj et al. 2005; De Lucia et al. 2006). The predicted star formation histories (SFHs) of early-type galaxies (at least in clusters) in the semi-analytical framework have been shown ...
... Universe and the (photometric) properties of the early-type population (e.g. Cole et al. 2000; Hatton et al. 2003; Kaviraj et al. 2005; De Lucia et al. 2006). The predicted star formation histories (SFHs) of early-type galaxies (at least in clusters) in the semi-analytical framework have been shown ...
NGC 3801 caught in the act: A post-merger starforming early
... HLS. Some diffuse and fainter emission is also seen in the intermediate region between spiral-wisp and the HLS. The western wisp is brighter than its eastern counterpart, but they extend up to similar distances (60′′ –70′′ or 14–16 kpc) from the centre of the galaxy. NUV wisps connect to an elongate ...
... HLS. Some diffuse and fainter emission is also seen in the intermediate region between spiral-wisp and the HLS. The western wisp is brighter than its eastern counterpart, but they extend up to similar distances (60′′ –70′′ or 14–16 kpc) from the centre of the galaxy. NUV wisps connect to an elongate ...
FOE 2017 Poster Contributions - College of Science | Oregon State
... the full data set have a small scatter they are also slightly biased: they systematically overestimate the true redshift when it is smaller than 2, and underestimate when the redshift is larger than 4. Finding an effective redshift estimator is a very important task, because many GRBs are needed to ...
... the full data set have a small scatter they are also slightly biased: they systematically overestimate the true redshift when it is smaller than 2, and underestimate when the redshift is larger than 4. Finding an effective redshift estimator is a very important task, because many GRBs are needed to ...
Light n-Capture Element Abundances in Metal
... 1957). The ultimate result of both type of processes is the same, a nucleus captures a neutron and increases its atomic mass. The difference between the two processes is the time scale over which they occur. In the s-process, the time between captures is on the order of thousands of years; while, in ...
... 1957). The ultimate result of both type of processes is the same, a nucleus captures a neutron and increases its atomic mass. The difference between the two processes is the time scale over which they occur. In the s-process, the time between captures is on the order of thousands of years; while, in ...
FLARESTARSINTHEORIONN EBULAREGION SUMARIO Durante
... observed spectroscopically -obtaining slit spectrograms of about 200 A/mm dispersion and with the equivalent spectral resolving power that Kraft and Greenstein (1969) used in their Pleiades star observations- even during minimum at least the very great majority would show emission lines, especially ...
... observed spectroscopically -obtaining slit spectrograms of about 200 A/mm dispersion and with the equivalent spectral resolving power that Kraft and Greenstein (1969) used in their Pleiades star observations- even during minimum at least the very great majority would show emission lines, especially ...
Cataclysmic Cosmic Events and How to Observe Them www.springer.com/series/5338
... joules we start moving into distinctly astronomical territory. The mildest events discussed in this book are the solar flares emitted by our own Sun that range in energy output from 1020 joules, for the barely detectable events, to the most violent flares, registering between 1025 and 1026 joules. F ...
... joules we start moving into distinctly astronomical territory. The mildest events discussed in this book are the solar flares emitted by our own Sun that range in energy output from 1020 joules, for the barely detectable events, to the most violent flares, registering between 1025 and 1026 joules. F ...
Science Planet Project-Uranus update final
... • Everything we know about Uranus comes from looking through a telescope. Only one spacecraft, Voyager 2, has ever made a close flyby of the planet. Astronomers suspect there is lots of water on Uranus. Since they’ve never actually sampled the surface of the planet, how could they know? ...
... • Everything we know about Uranus comes from looking through a telescope. Only one spacecraft, Voyager 2, has ever made a close flyby of the planet. Astronomers suspect there is lots of water on Uranus. Since they’ve never actually sampled the surface of the planet, how could they know? ...
Current astrometric surveys
... – Strong role for ground-based astrometry until Gaia results are available. • After Gaia proper motions and positions will be determined from the ground using a Gaia reference frame. ...
... – Strong role for ground-based astrometry until Gaia results are available. • After Gaia proper motions and positions will be determined from the ground using a Gaia reference frame. ...
The Spitzer/GLIMPSE Surveys - UW-Madison Astronomy
... filaments that are prevalent among IRDC morphologies. Differential Galactic rotation also tends to stretch large molecular clouds into linear structures, but this mechanism would only distort in the plane of the Galaxy leaving the wiggly filamentary structures unexplained. Perhaps the wiggles perpen ...
... filaments that are prevalent among IRDC morphologies. Differential Galactic rotation also tends to stretch large molecular clouds into linear structures, but this mechanism would only distort in the plane of the Galaxy leaving the wiggly filamentary structures unexplained. Perhaps the wiggles perpen ...
Revisiting the Hubble sequence in the SDSS DR7
... fainter than the limiting magnitude of the training sample. Therefore, it is very important to check that these faint galaxies are not systematically misclassified just because they are not represented in the training. As a first check, we computed the probability distributions of bright (mg < 16) a ...
... fainter than the limiting magnitude of the training sample. Therefore, it is very important to check that these faint galaxies are not systematically misclassified just because they are not represented in the training. As a first check, we computed the probability distributions of bright (mg < 16) a ...
An Atlas of Stellar Spectra
... of a group of stars of the same spectral type and luminosity class can be determined with great precision, even when the group consists of a relatively small number of stars. Even for individual stars distances of good accuracy can be derived. A corresponding gain is made in problems concerned with ...
... of a group of stars of the same spectral type and luminosity class can be determined with great precision, even when the group consists of a relatively small number of stars. Even for individual stars distances of good accuracy can be derived. A corresponding gain is made in problems concerned with ...
Cosmic distance ladder
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A real direct distance measurement of an astronomical object is possible only for those objects that are ""close enough"" (within about a thousand parsecs) to Earth. The techniques for determining distances to more distant objects are all based on various measured correlations between methods that work at close distances and methods that work at larger distances. Several methods rely on a standard candle, which is an astronomical object that has a known luminosity.The ladder analogy arises because no one technique can measure distances at all ranges encountered in astronomy. Instead, one method can be used to measure nearby distances, a second can be used to measure nearby to intermediate distances, and so on. Each rung of the ladder provides information that can be used to determine the distances at the next higher rung.