Microlensing Events by Proxima Centauri in 2014 and 2016
... between the parallaxes of the lens and the source. The parallax of the lens is already known, and our planned HST observations will directly constrain the source parallaxes (expected to be very small as noted above). For the upcoming close encounters of Proxima Centauri, the sources lie on either si ...
... between the parallaxes of the lens and the source. The parallax of the lens is already known, and our planned HST observations will directly constrain the source parallaxes (expected to be very small as noted above). For the upcoming close encounters of Proxima Centauri, the sources lie on either si ...
T3-Cosmic Star Formation History
... global history of star formation and heavy element production of the Universe, independently of the complex evolutionary phases of individual galaxy subpopulations. The modern version of this technique relies on some basic properties of stellar populations and dusty starburst galaxies: 1. The UV-con ...
... global history of star formation and heavy element production of the Universe, independently of the complex evolutionary phases of individual galaxy subpopulations. The modern version of this technique relies on some basic properties of stellar populations and dusty starburst galaxies: 1. The UV-con ...
Astronomy 113 Laboratory Manual - UW
... Section 4: The Polaris Experiment Polaris, the North Star, has long shown the way to travelers. At sea the only "landmarks" are celestial. It was Polaris that guided sailors around the globe, and not only by showing the way North. Using a sextant a European captain sailing to the New World could als ...
... Section 4: The Polaris Experiment Polaris, the North Star, has long shown the way to travelers. At sea the only "landmarks" are celestial. It was Polaris that guided sailors around the globe, and not only by showing the way North. Using a sextant a European captain sailing to the New World could als ...
How plausible are the proposed formation scenarios of CEMP
... CEMP-r/s stars are metal-poor stars with enhanced abundances of carbon and heavy elements associated with the slow and rapid neutron capture process (s- and r-elements, respectively). It is believed that carbon and s-elements were accreted in the past from the wind of a primary star in the asymptoti ...
... CEMP-r/s stars are metal-poor stars with enhanced abundances of carbon and heavy elements associated with the slow and rapid neutron capture process (s- and r-elements, respectively). It is believed that carbon and s-elements were accreted in the past from the wind of a primary star in the asymptoti ...
My capstone project
... analogy is useful in another way. Much like most of the mass of an egg is in the yolk, most of the mass of the stars in a galaxy is concentrated in the bulge. Unlike egg whites, stars in the disc move around the central bulge of a spiral galaxy in orbits shaped like the orbits of planets around our ...
... analogy is useful in another way. Much like most of the mass of an egg is in the yolk, most of the mass of the stars in a galaxy is concentrated in the bulge. Unlike egg whites, stars in the disc move around the central bulge of a spiral galaxy in orbits shaped like the orbits of planets around our ...
Markov Chain Monte Carlo Modeling of High-Redshift Quasar
... the radio source 3C 273. It was found to have a blue non-thermal power-law continuum spectrum Fν ∝ ν 0.28 (Oke 1963), where Fν is the flux density per unit frequency and ν is the frequency. The power-law spectrum was punctuated by extremely broad emission lines (equivalent widths of '50 Å), indicat ...
... the radio source 3C 273. It was found to have a blue non-thermal power-law continuum spectrum Fν ∝ ν 0.28 (Oke 1963), where Fν is the flux density per unit frequency and ν is the frequency. The power-law spectrum was punctuated by extremely broad emission lines (equivalent widths of '50 Å), indicat ...
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Physics Department Physics 8.286: The Early Universe
... their distances measured by parallax using the orbit of the Earth. The vast majority of these were measured by the Hipparcos satellite, launched in 1989. This was a very important achievement, because among other benefits it allowed astronomers to recalibrate their distance and age estimates for glo ...
... their distances measured by parallax using the orbit of the Earth. The vast majority of these were measured by the Hipparcos satellite, launched in 1989. This was a very important achievement, because among other benefits it allowed astronomers to recalibrate their distance and age estimates for glo ...
Hubble Deep Field Academy -- Overview
... description, the concepts covered, prerequisites, and the target audience. Science Background: Provides information about the science behind the activity. It clarifies important concepts used in the activity and contains a message from the scientist who worked with the team to develop it. Lesson Pla ...
... description, the concepts covered, prerequisites, and the target audience. Science Background: Provides information about the science behind the activity. It clarifies important concepts used in the activity and contains a message from the scientist who worked with the team to develop it. Lesson Pla ...
Mapping of the extinction in giant molecular clouds using optical star
... using an adaptive grid and a wavelet decomposition applied to the optical data provided by the USNO-Precision Measuring Machine. The distribution of the extinction in the clouds leads to estimate their total individual masses M and their maximum of extinction. I show that the relation between the ma ...
... using an adaptive grid and a wavelet decomposition applied to the optical data provided by the USNO-Precision Measuring Machine. The distribution of the extinction in the clouds leads to estimate their total individual masses M and their maximum of extinction. I show that the relation between the ma ...
Astronomy Astrophysics Kuiper belts around nearby stars &
... very extended dust, originating in Kuiper-belt analogues (of the order of 100 AU from the star), observations at submillimetre (submm) wavelengths are needed. Although very few older stars show evidence of hot dust, likely due to clearing by planets (e.g. Beichman et al. 2006b; Meyer et al. 2008), c ...
... very extended dust, originating in Kuiper-belt analogues (of the order of 100 AU from the star), observations at submillimetre (submm) wavelengths are needed. Although very few older stars show evidence of hot dust, likely due to clearing by planets (e.g. Beichman et al. 2006b; Meyer et al. 2008), c ...
Star Formation and Dynamics in the Galactic Centre
... Fig. 2 Left-hand panel: estimate of the enclosed mass versus projected distance (black line), derived with the Bahcall-Tremaine (BT, Bahcall & Tremaine 1981) mass estimator, assuming a broken power-law structure of the stellar cluster and a constant line-of-sight velocity dispersion outside of the b ...
... Fig. 2 Left-hand panel: estimate of the enclosed mass versus projected distance (black line), derived with the Bahcall-Tremaine (BT, Bahcall & Tremaine 1981) mass estimator, assuming a broken power-law structure of the stellar cluster and a constant line-of-sight velocity dispersion outside of the b ...
Document
... in the Galaxy. On a grander scale, the Milky Way is embedded in an even larger halo of invisible dark matter. Catalogues of stellar positions based on ground-based observations are limited in precision by the turbulence of Earth’s atmosphere. Another limitation is that they can probe at most some th ...
... in the Galaxy. On a grander scale, the Milky Way is embedded in an even larger halo of invisible dark matter. Catalogues of stellar positions based on ground-based observations are limited in precision by the turbulence of Earth’s atmosphere. Another limitation is that they can probe at most some th ...
A Teacher`s Guide to the Universe
... all of these systems together is gravity. Each of these structures is formed out of smaller building blocks, so the higher the level of structure the bigger the structure gets. In other words, as you build a building out of bricks the building becomes bigger than the bricks. Cities become even bigge ...
... all of these systems together is gravity. Each of these structures is formed out of smaller building blocks, so the higher the level of structure the bigger the structure gets. In other words, as you build a building out of bricks the building becomes bigger than the bricks. Cities become even bigge ...
MORPHOLOGICAL CLASSIFICATION OF GALAXIES INTO
... Google Earth and found that their approach was quite successful in detecting regular shapes in these images. The authors in [11] trained a convolutional neural network to classify the 1.2 million images in the Image Net LSVRC-2010 contest into 1000 different classes. This was a deep learning approac ...
... Google Earth and found that their approach was quite successful in detecting regular shapes in these images. The authors in [11] trained a convolutional neural network to classify the 1.2 million images in the Image Net LSVRC-2010 contest into 1000 different classes. This was a deep learning approac ...
Finding high-redshift dark stars with the James Webb Space
... using the JWST. When attempting to assess the detectability of dark stars at high redshifts, the expected lifespan of such objects represents a crucial aspect. In principle, dark stars could live indefinitely, provided that there is ample dark matter available to fuel them. Dark stars are powered by ...
... using the JWST. When attempting to assess the detectability of dark stars at high redshifts, the expected lifespan of such objects represents a crucial aspect. In principle, dark stars could live indefinitely, provided that there is ample dark matter available to fuel them. Dark stars are powered by ...
PDF - NMSU Astronomy
... wavelength of spectral lines in nanometers, and measure the sizes of features on the Sun that are larger than 100,000 kilometers. ...
... wavelength of spectral lines in nanometers, and measure the sizes of features on the Sun that are larger than 100,000 kilometers. ...
(Download from http://astronomy.nmsu.edu/astro/) c NMSU
... wavelength of spectral lines in nanometers, and measure the sizes of features on the Sun that are larger than 100,000 kilometers. ...
... wavelength of spectral lines in nanometers, and measure the sizes of features on the Sun that are larger than 100,000 kilometers. ...
arXiv:astro-ph/9712176v1 15 Dec 1997
... for good seeing conditions. The three individual exposures did not produce significant differences within the errors. Line strength indices were derived following Faber et al. (1985) and Worthey (1992) from flux calibrated spectra, rebinned radially as before. Furthermore, we corrected for velocity ...
... for good seeing conditions. The three individual exposures did not produce significant differences within the errors. Line strength indices were derived following Faber et al. (1985) and Worthey (1992) from flux calibrated spectra, rebinned radially as before. Furthermore, we corrected for velocity ...
L43 THE STARFISH TWINS: TWO YOUNG
... N1 with S4, N2 with S3, and N3 with S1 is equally plausible. A comparison of the fluxes of both PNs at different wavelengths indicates that they are intrinsically similar in size and brightness but are located at different distances. We find that the stellar blue and visual (continuum) fluxes, the H ...
... N1 with S4, N2 with S3, and N3 with S1 is equally plausible. A comparison of the fluxes of both PNs at different wavelengths indicates that they are intrinsically similar in size and brightness but are located at different distances. We find that the stellar blue and visual (continuum) fluxes, the H ...
Rapid Rotation of Low-Mass Red Giants Using APOKASC: A
... Spuriously high measurements of broadening (individual measurements more than five times the values measured for the other two wavelength sections) arose in a few cases where the template spectrum was already broader than the observed spectrum or did not fit well. These values were removed and the m ...
... Spuriously high measurements of broadening (individual measurements more than five times the values measured for the other two wavelength sections) arose in a few cases where the template spectrum was already broader than the observed spectrum or did not fit well. These values were removed and the m ...
2. The X-ray-Radio correlation for bulgeless galaxies
... evolution of massive stars and their destruction, suggesting the possibility of using X-ray emission to determine the star formation rates. This work presents a study on the presence of this correlation in bulgeless galaxies at intermediate redshifts ( 0.4≤z≤1.0 ). To this effect, the VLA and Chandr ...
... evolution of massive stars and their destruction, suggesting the possibility of using X-ray emission to determine the star formation rates. This work presents a study on the presence of this correlation in bulgeless galaxies at intermediate redshifts ( 0.4≤z≤1.0 ). To this effect, the VLA and Chandr ...
Testing MOND gravity in the shell galaxy NGC 3923
... brightness, which does not necessarily need to be the same as the position of the edge. This uncertainty of radii of the shells reaches several percent. The shell edges form almost spherical caps. Therefore, the three-dimensional radius of a shell must be the same as the projected one. There are fiv ...
... brightness, which does not necessarily need to be the same as the position of the edge. This uncertainty of radii of the shells reaches several percent. The shell edges form almost spherical caps. Therefore, the three-dimensional radius of a shell must be the same as the projected one. There are fiv ...
On the role of the WNH phase in the evolution of very massive stars
... They noted that this relation might not be adequate for WNH stars, but they also note that when masses measured in binary systems are available for the same stars for which they estimated a spectroscopic mass, the two methods show no wild disagreement. For example, the spectroscopic mass they derive ...
... They noted that this relation might not be adequate for WNH stars, but they also note that when masses measured in binary systems are available for the same stars for which they estimated a spectroscopic mass, the two methods show no wild disagreement. For example, the spectroscopic mass they derive ...
The Case for an Accelerating Universe from
... Cosmology Project (SCP) in the detection rate of highredshift SNe Ia by employing large-format CCDs, largeaperture telescopes, and more sophisticated image-analysis techniques (Perlmutter et al. 1995). These advances led to the detection of seven SNe Ia at z B 0.4 between 1992 and 1994, yielding a c ...
... Cosmology Project (SCP) in the detection rate of highredshift SNe Ia by employing large-format CCDs, largeaperture telescopes, and more sophisticated image-analysis techniques (Perlmutter et al. 1995). These advances led to the detection of seven SNe Ia at z B 0.4 between 1992 and 1994, yielding a c ...
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.