Morphology and Environment
... small galaxies. There is tantalizing evidence for intergalactic neutral hydrogen in the form of so-called “high-velocity clouds”. The local group is still collapsing from a point of maximum expansion. Other loose groups, such as the M81 system, are less extended and have undergone some dynamical evo ...
... small galaxies. There is tantalizing evidence for intergalactic neutral hydrogen in the form of so-called “high-velocity clouds”. The local group is still collapsing from a point of maximum expansion. Other loose groups, such as the M81 system, are less extended and have undergone some dynamical evo ...
z= 1000 - z= 10
... are no metals •Molecular hydrogen is the only significant cooling in primordial gas •Molecular hydrogen usually forms on dust…but there is no dust ...
... are no metals •Molecular hydrogen is the only significant cooling in primordial gas •Molecular hydrogen usually forms on dust…but there is no dust ...
Chapter 30: Stars
... made by the same element. Thus, by comparing laboratory spectra of different gases with the dark lines in the solar spectrum, it is possible to identify the elements that make up the Sun’s outer layers. You will experiment with identifying spectral lines in the GeoLab at the end of this chapter. ...
... made by the same element. Thus, by comparing laboratory spectra of different gases with the dark lines in the solar spectrum, it is possible to identify the elements that make up the Sun’s outer layers. You will experiment with identifying spectral lines in the GeoLab at the end of this chapter. ...
General Astrophysics And Comparative Planetology
... The size of a planet is key to many of its properties, including its albedo and thermal emission. A measured radius is especially important for classifying new kinds of planets such as super Earths, ocean planets, and planets around non-solar type stars (e.g., Kuchner 2003). Figure 2 shows the masse ...
... The size of a planet is key to many of its properties, including its albedo and thermal emission. A measured radius is especially important for classifying new kinds of planets such as super Earths, ocean planets, and planets around non-solar type stars (e.g., Kuchner 2003). Figure 2 shows the masse ...
Cold Gas and Star Formation in Elliptical Galaxies
... than a few µm. Long wavelength emission is also detected towards a significant fraction of early-type galaxies by IRAS (12µm, 25µm, 60µm and 100µm), ISO (between about 5µm and 200 µm; Malhotra et al. 1998, S. Madden, this conference) and at submillimeter wavelengths. The largest sample available is ...
... than a few µm. Long wavelength emission is also detected towards a significant fraction of early-type galaxies by IRAS (12µm, 25µm, 60µm and 100µm), ISO (between about 5µm and 200 µm; Malhotra et al. 1998, S. Madden, this conference) and at submillimeter wavelengths. The largest sample available is ...
The Hipparcos Star Globe Booklet - Cosmos
... cluster, the ‘jaw’ of the bull in the Taurus constellation. The data showed that some of the stars that were apparently part of this cluster were impostors: they are not in fact travelling with the cluster, and over time will part company with its true members. ...
... cluster, the ‘jaw’ of the bull in the Taurus constellation. The data showed that some of the stars that were apparently part of this cluster were impostors: they are not in fact travelling with the cluster, and over time will part company with its true members. ...
Atoms and Stars IST 3360 and IST 1990
... Built great observatories on his island Fights, duels, possibly died from being drunk, but also careful astronomical measurements • Convinced astronomy needed good measurements ...
... Built great observatories on his island Fights, duels, possibly died from being drunk, but also careful astronomical measurements • Convinced astronomy needed good measurements ...
Annual report 2004 - Département d`Astrophysique, Géophysique et
... spectrum and to identify the pulsation modes. Finally, if successful in the latter, an asteroseismological analysis will be performed in order to gain insight into the stellar structure and other physical properties of the pulsating star. A full dynamical analysis of the binary was performed. We fin ...
... spectrum and to identify the pulsation modes. Finally, if successful in the latter, an asteroseismological analysis will be performed in order to gain insight into the stellar structure and other physical properties of the pulsating star. A full dynamical analysis of the binary was performed. We fin ...
![Cosmic variance in [O/Fe] in the Galactic disk](http://s1.studyres.com/store/data/014331057_1-996ec6eddf93071c5e835624d4620c7e-300x300.png)
Cosmic variance in [O/Fe] in the Galactic disk
... of stars to the interstellar medium (ISM). At a given location within a galaxy, slower supernova (or star formation) rates and higher variance in the yields from different stars will contribute to higher cosmic variance in chemical abundances. If two metals are produced in the same proportions in su ...
... of stars to the interstellar medium (ISM). At a given location within a galaxy, slower supernova (or star formation) rates and higher variance in the yields from different stars will contribute to higher cosmic variance in chemical abundances. If two metals are produced in the same proportions in su ...
Astronomy 114 - Department of Astronomy
... Interstellar gas and dust are common in the disk of the Galaxy Interstellar medium (ISM) Diffuse gas (atomic H and molecular hydrogen H2 ) Dust (formed in the envelopes of stars) ...
... Interstellar gas and dust are common in the disk of the Galaxy Interstellar medium (ISM) Diffuse gas (atomic H and molecular hydrogen H2 ) Dust (formed in the envelopes of stars) ...
Unit 13―The “Fixed” Stars
... and so jump by whole factors of 100 on the energy or luminosity scale, but we need to know luminosity values for single values of magnitude. That means we are looking for a number which when multiplied by its self five times equals 100. That is called the “fifth-root of 100.” And the ancients stuck ...
... and so jump by whole factors of 100 on the energy or luminosity scale, but we need to know luminosity values for single values of magnitude. That means we are looking for a number which when multiplied by its self five times equals 100. That is called the “fifth-root of 100.” And the ancients stuck ...
NSDL/NSTA Web Seminar: Celebrating Astronomy: A Star`s Story
... http://www.compadre.org/Astronomy Hubble Space Telescope http://hubblesite.org International Year of Astronomy 2009 http://astronomy2009.us http://astronomy2009.org ...
... http://www.compadre.org/Astronomy Hubble Space Telescope http://hubblesite.org International Year of Astronomy 2009 http://astronomy2009.us http://astronomy2009.org ...
Celebrating Astronomy: The Life of a Star
... http://www.compadre.org/Astronomy Hubble Space Telescope http://hubblesite.org International Year of Astronomy 2009 http://astronomy2009.us http://astronomy2009.org ...
... http://www.compadre.org/Astronomy Hubble Space Telescope http://hubblesite.org International Year of Astronomy 2009 http://astronomy2009.us http://astronomy2009.org ...
Feedback in low-mass galaxies in the early Universe
... that fast outflows in some massive galaxies may be powered by starbursts rather than by active galactic nuclei38,39. At lower masses, the decreasing efficiency of star formation is likely to be due to processes associated with the formation and evolution of massive stars. Galactic winds are driven b ...
... that fast outflows in some massive galaxies may be powered by starbursts rather than by active galactic nuclei38,39. At lower masses, the decreasing efficiency of star formation is likely to be due to processes associated with the formation and evolution of massive stars. Galactic winds are driven b ...
Gilmore - Astrometry and Astrophysics in the Gaia sky
... shape and rotation of bulge, disk and halo internal motions of star forming regions, clusters, etc nature of spiral arms and the stellar warp space motions of all Galactic satellite systems ...
... shape and rotation of bulge, disk and halo internal motions of star forming regions, clusters, etc nature of spiral arms and the stellar warp space motions of all Galactic satellite systems ...
the solar neighborhood. xi. the trigonometric parallax of scr
... single, stellar images that are not affected by proximity to bright stars were selected as local astrometric reference stars. These reference stars were used to fit linear models for each of the plates with respect to the array of mean reference star positions. The residual errors from the reference ...
... single, stellar images that are not affected by proximity to bright stars were selected as local astrometric reference stars. These reference stars were used to fit linear models for each of the plates with respect to the array of mean reference star positions. The residual errors from the reference ...
Neutron Stars
... Periods shorter than this do not exist (such as in the previous calculation) because the object would have to rotate so fast it would overcome gravity and fly apart. ...
... Periods shorter than this do not exist (such as in the previous calculation) because the object would have to rotate so fast it would overcome gravity and fly apart. ...
BARS FROM THE INSIDE OUT: AN HST STUDY OF THEIR DUSTY
... emphasize structures on the scale of the PSF and deemphasize larger-scale spatial variations. In all of the structure maps shown here, dusty regions are dark and emission regions, such as star formation knots, are bright. Figure 3 shows images, color maps, and structure maps of four representative g ...
... emphasize structures on the scale of the PSF and deemphasize larger-scale spatial variations. In all of the structure maps shown here, dusty regions are dark and emission regions, such as star formation knots, are bright. Figure 3 shows images, color maps, and structure maps of four representative g ...
... the 2001 season, we could not resolve the pair. In 2000, the sky conditions were better and the star could be separated from the blend in all our images. Although noisy, the light curve phased with a period of about 1.15 days is shown in Figure 3. As seen, the star is indeed variable and brighter th ...
Constellation Classification Cards*
... Negative numbers, e.g., Sirius = -1.46, are the brightest stars; the highest positive numbers, e.g., Thuban = 3.65, are the dimmest stars. For Set B, there are six cards with three numbers. Stars with three numbers and a slash, e.g., Mintaka = 2.23 (3.2/3.3), are binary stars. Use the first number g ...
... Negative numbers, e.g., Sirius = -1.46, are the brightest stars; the highest positive numbers, e.g., Thuban = 3.65, are the dimmest stars. For Set B, there are six cards with three numbers. Stars with three numbers and a slash, e.g., Mintaka = 2.23 (3.2/3.3), are binary stars. Use the first number g ...
The 2008 RBSE Journal - National Optical Astronomy Observatory
... and usually end up being bigger than the originating galaxy. The smallest known are only a few tens of parsecs across, while the largest are known to be up to several megaparsecs. The average radio galaxy is usually typically hundreds of kiloparsecs across. This is about twice the size of the Milky ...
... and usually end up being bigger than the originating galaxy. The smallest known are only a few tens of parsecs across, while the largest are known to be up to several megaparsecs. The average radio galaxy is usually typically hundreds of kiloparsecs across. This is about twice the size of the Milky ...
THE PROPERTIES OF MAIN-SEQUENCE STARS - Cosmos
... of declination ,26 that (i) have MK spectral types in the Michigan catalogues and (ii) had spectroscopic parallaxes that placed them within 80 pc of the Sun. Of these, 3727 are well determined as luminosity class V and actually lie within 100 pc. From this subsample we can determine the distributio ...
... of declination ,26 that (i) have MK spectral types in the Michigan catalogues and (ii) had spectroscopic parallaxes that placed them within 80 pc of the Sun. Of these, 3727 are well determined as luminosity class V and actually lie within 100 pc. From this subsample we can determine the distributio ...
Big Bang Theory
... confirmed that these “nebulae” were in fact other galaxies much like our own Milky Way. In 1912 another American astronomer, Vesto Slipher, analyzed spectrographs of galaxies and measured their redshift. Hubble combined Slipher’s redshift data with his measurements of galactic distances to see how t ...
... confirmed that these “nebulae” were in fact other galaxies much like our own Milky Way. In 1912 another American astronomer, Vesto Slipher, analyzed spectrographs of galaxies and measured their redshift. Hubble combined Slipher’s redshift data with his measurements of galactic distances to see how t ...
P7 Further Physics : Observing the Universe
... materials introduces atomic and nuclear structure, neutrons, and protons – but not the evidence for them. ...
... materials introduces atomic and nuclear structure, neutrons, and protons – but not the evidence for them. ...
The effect of the environment on the HI scaling relations
... already known, but a detailed quantification of their properties, crucial for a comparison with models, was still missing. Luckily, the situation is rapidly changing for 21 cm studies. The advent of large Hi surveys, such as the Arecibo Legacy Fast ALFA Survey (Giovanelli et al. 2005), which eventua ...
... already known, but a detailed quantification of their properties, crucial for a comparison with models, was still missing. Luckily, the situation is rapidly changing for 21 cm studies. The advent of large Hi surveys, such as the Arecibo Legacy Fast ALFA Survey (Giovanelli et al. 2005), which eventua ...
H II region
An H II region is a large, low-density cloud of partially ionized gas in which star formation has recently taken place. The short-lived blue stars forged in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. The first known H II region was the Orion Nebula, which was discovered in 1610 by Nicolas-Claude Fabri de Peiresc.H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II, pronounced H-two by astronomers (an H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). Such regions have extremely diverse shapes, because the distribution of the stars and gas inside them is irregular. They often appear clumpy and filamentary, sometimes showing bizarre shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster of birthed stars such as the Pleiades.H II regions can be seen to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies. Spiral and irregular galaxies contain many H II regions, while elliptical galaxies are almost devoid of them. In the spiral galaxies, including the Milky Way, H II regions are concentrated in the spiral arms, while in the irregular galaxies they are distributed chaotically. Some galaxies contain huge H II regions, which may contain tens of thousands of stars. Examples include the 30 Doradus region in the Large Magellanic Cloud and NGC 604 in the Triangulum Galaxy.