arXiv:1502.04693v1 [gr
... We present a sample of brown dwarfs identified with the Wide-field Infrared Survey Explorer (WISE) for which we have obtained Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) near-infrared grism spectroscopy. The sample (twenty-two in total) was observed with the G141 grism covering 1.10−1.70 ...
... We present a sample of brown dwarfs identified with the Wide-field Infrared Survey Explorer (WISE) for which we have obtained Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) near-infrared grism spectroscopy. The sample (twenty-two in total) was observed with the G141 grism covering 1.10−1.70 ...
On the nature and detectability of Type Ib/c supernova progenitors
... YWL21) end their lives while they are filling their Rochelobes during Case ABB or BB mass transfer (i.e., mass transfer from the He star during/after the carbon-oxygen core contraction phase; see Yoon et al. 2010 for more details). For comparison, the evolutionary track of a single, pure helium star ...
... YWL21) end their lives while they are filling their Rochelobes during Case ABB or BB mass transfer (i.e., mass transfer from the He star during/after the carbon-oxygen core contraction phase; see Yoon et al. 2010 for more details). For comparison, the evolutionary track of a single, pure helium star ...
Precision age indicators that exploit chemically peculiar stars
... still of great value, blue photometric colors generally indicate galaxies with ongoing star formation, while red colors indicate galaxies that have not formed significant numbers of stars in the last few hundred million years. A technique that often gives higher precision is using Balmer feature str ...
... still of great value, blue photometric colors generally indicate galaxies with ongoing star formation, while red colors indicate galaxies that have not formed significant numbers of stars in the last few hundred million years. A technique that often gives higher precision is using Balmer feature str ...
Lives of the Stars Lecture 5: Star birth
... easily destroyed. Helium-4 is the only really stable one, so lots of Helium-4 was formed in the next few seconds. But apart from tiny amounts of Lithium-7, no other element can be easily formed. So when the era of fusion ended, about 3½ minutes after the Big Bang, the universe consisted of lots of h ...
... easily destroyed. Helium-4 is the only really stable one, so lots of Helium-4 was formed in the next few seconds. But apart from tiny amounts of Lithium-7, no other element can be easily formed. So when the era of fusion ended, about 3½ minutes after the Big Bang, the universe consisted of lots of h ...
our knowledge of high-mass star formation at the dawn of - CEA-Irfu
... high-mass star formation have been called massive starless or pre-stellar cores, massive cold molecular cores, or even infrared-dark clouds. In the subsequent phase, they have been named massive protostars, high-mass protostellar objects, or hot molecular cores. The better-known final phase would co ...
... high-mass star formation have been called massive starless or pre-stellar cores, massive cold molecular cores, or even infrared-dark clouds. In the subsequent phase, they have been named massive protostars, high-mass protostellar objects, or hot molecular cores. The better-known final phase would co ...
Chapter 12
... however, are as massive as 30 times the Sun’s mass (30 M) and are much hotter than the Sun and blue in color. Others are much less massive than the Sun, only one-tenth its mass, and are cool, red, and dim. Moreover, even stars similar to the Sun in composition and mass may differ enormously from it ...
... however, are as massive as 30 times the Sun’s mass (30 M) and are much hotter than the Sun and blue in color. Others are much less massive than the Sun, only one-tenth its mass, and are cool, red, and dim. Moreover, even stars similar to the Sun in composition and mass may differ enormously from it ...
Option D – Astrophysics
... The Sun and all the objects orbiting it are collectively known as the solar system. Our Sun is a star and it is very similar to billions of other stars in the universe. It has many objects orbiting around it that are held in their orbits by gravity. The solar system is an example of a planetary syst ...
... The Sun and all the objects orbiting it are collectively known as the solar system. Our Sun is a star and it is very similar to billions of other stars in the universe. It has many objects orbiting around it that are held in their orbits by gravity. The solar system is an example of a planetary syst ...
arXiv:astro-ph/0508448v1 22 Aug 2005
... notable that, in all five of the Galactic WC+O systems with measured masses, the WC star (which is a stripped core nearing the very end of its lifetime) is more massive than 8 M⊙ . These systems also have massive O star companions (23 – 34 M⊙ , van der Hucht 2001) which will quite probably still be ...
... notable that, in all five of the Galactic WC+O systems with measured masses, the WC star (which is a stripped core nearing the very end of its lifetime) is more massive than 8 M⊙ . These systems also have massive O star companions (23 – 34 M⊙ , van der Hucht 2001) which will quite probably still be ...
Today in Astronomy 102: black hole observations, v.2
... Discovery of “stellar” black holes: GRO J1655-40 GRO J1655-40 (a.k.a. Nova Scorpii 1994) is an X-ray transient source discovered by NASA’s Compton Gamma-Ray Observatory (GRO) in 1994. Rapidly-variable emission in its X-ray bursts: the X-ray object is a few hundred km around. The X-ray source ha ...
... Discovery of “stellar” black holes: GRO J1655-40 GRO J1655-40 (a.k.a. Nova Scorpii 1994) is an X-ray transient source discovered by NASA’s Compton Gamma-Ray Observatory (GRO) in 1994. Rapidly-variable emission in its X-ray bursts: the X-ray object is a few hundred km around. The X-ray source ha ...
Document
... – Open clusters are loosely packed and contain up to a few thousand stars. – Globular clusters are densely packed and contain hundreds of thousands of stars. • How do we measure the age of a star cluster? – A star cluster's age roughly equals the life expectancy of its most massive stars still on th ...
... – Open clusters are loosely packed and contain up to a few thousand stars. – Globular clusters are densely packed and contain hundreds of thousands of stars. • How do we measure the age of a star cluster? – A star cluster's age roughly equals the life expectancy of its most massive stars still on th ...
astronomy advisory panel strategy
... clusters via the Sunyaev-Zel’dovich (S-Z) effect. The formation and development of Galaxies Planck will perform all-sky survey of dusty galaxies and AGN down to fluxes of tens of mJy and investigate the demographics and evolution of dusty star-forming galaxies. The mission will allow a detailed cens ...
... clusters via the Sunyaev-Zel’dovich (S-Z) effect. The formation and development of Galaxies Planck will perform all-sky survey of dusty galaxies and AGN down to fluxes of tens of mJy and investigate the demographics and evolution of dusty star-forming galaxies. The mission will allow a detailed cens ...
When we look at a neighboring galaxy (such as M31, the
... this year, Maria Drout from the University of Iowa, who came to Lowell through the Research Experiences for Undergraduates (REU) program run through the National Science Foundation. Maria not only was able to separate the wheat from the chaff, but also carried the analysis to the point of drafting a ...
... this year, Maria Drout from the University of Iowa, who came to Lowell through the Research Experiences for Undergraduates (REU) program run through the National Science Foundation. Maria not only was able to separate the wheat from the chaff, but also carried the analysis to the point of drafting a ...
Early-type stars in the core of the young open cluster Westerlund 2
... is dominated by strong and broad H Balmer lines. Weak absorption lines of He λλ 4388, 4471, Mg λ 4481 and Si λ 4552 are also seen. The He λ 4471/Mg λ 4481 intensity ratio indicates a spectral type B8-A0. The appearance of some weak metallic lines favours an A0 classification, whilst ...
... is dominated by strong and broad H Balmer lines. Weak absorption lines of He λλ 4388, 4471, Mg λ 4481 and Si λ 4552 are also seen. The He λ 4471/Mg λ 4481 intensity ratio indicates a spectral type B8-A0. The appearance of some weak metallic lines favours an A0 classification, whilst ...
White dwarf cooling sequences and cosmochronology
... remaining quantities, the initial mass function, (M), and the star formation rate, (t), are not known a priori and depend on the astronomical properties of the stellar population under study. Since the total density of white dwarfs of a given population is not usually well known, to compare the th ...
... remaining quantities, the initial mass function, (M), and the star formation rate, (t), are not known a priori and depend on the astronomical properties of the stellar population under study. Since the total density of white dwarfs of a given population is not usually well known, to compare the th ...
The evolution of spiral galaxies in clusters Kutdemir, Elif
... Evidence have been accumulating, mainly from HI studies, on the importance of cold gas accretion in the local universe: A large number of galaxies are accompanied by gas-rich dwarfs or are surrounded by HI cloud complexes, tails and filaments (Sancisi et al. 2008). Most of the high-velocity clouds a ...
... Evidence have been accumulating, mainly from HI studies, on the importance of cold gas accretion in the local universe: A large number of galaxies are accompanied by gas-rich dwarfs or are surrounded by HI cloud complexes, tails and filaments (Sancisi et al. 2008). Most of the high-velocity clouds a ...
View the sky`s greatest nebula
... In the winter, we see the sky opposite the stellar traffic jam found toward the galaxy’s center. The winter Milky Way is there, but you need a dark sky to see it with unaided eyes. The winter sky is the brightest of the seasonal skies — it contains the highest concentration of bright stars — and its ...
... In the winter, we see the sky opposite the stellar traffic jam found toward the galaxy’s center. The winter Milky Way is there, but you need a dark sky to see it with unaided eyes. The winter sky is the brightest of the seasonal skies — it contains the highest concentration of bright stars — and its ...
Galaxy Formation and Evolution
... must involve cosmology, the study of the properties of space-time on large scales. Modern cosmology is based upon the Cosmological Principle, the hypothesis that the Universe is spatially homogeneous and isotropic, and Einstein’s theory of General Relativity, according to which the structure of spac ...
... must involve cosmology, the study of the properties of space-time on large scales. Modern cosmology is based upon the Cosmological Principle, the hypothesis that the Universe is spatially homogeneous and isotropic, and Einstein’s theory of General Relativity, according to which the structure of spac ...
Galaxies
... Galaxy mass measurements show that galaxies need between 3 and 10 times more mass than can be observed to explain their rotation curves. The discrepancy is even larger in galaxy clusters, which need 10 to 100 times more mass. The total needed is more than the sum of the dark matter associated with e ...
... Galaxy mass measurements show that galaxies need between 3 and 10 times more mass than can be observed to explain their rotation curves. The discrepancy is even larger in galaxy clusters, which need 10 to 100 times more mass. The total needed is more than the sum of the dark matter associated with e ...
A Comet-Hunter`s Legacy -
... interaction. M81's bright spiral arms are the site of star formation, partially caused by density waves raised by the most recent passage of M82, and the central portion of M82 is undergoing a starburst -- an explosively rapid surge of star formation and death -- which is violently blowing huge amou ...
... interaction. M81's bright spiral arms are the site of star formation, partially caused by density waves raised by the most recent passage of M82, and the central portion of M82 is undergoing a starburst -- an explosively rapid surge of star formation and death -- which is violently blowing huge amou ...
Perseus (constellation)
Perseus, named after the Greek mythological hero Perseus, is a constellation in the northern sky. It was one of 48 listed by the 2nd-century astronomer Ptolemy and among the 88 modern constellations defined by the International Astronomical Union (IAU). It is located in the northern celestial hemisphere near several other constellations named after legends surrounding Perseus, including Andromeda to the west and Cassiopeia to the north. Perseus is also bordered by Aries and Taurus to the south, Auriga to the east, Camelopardalis to the north, and Triangulum to the west.The galactic plane of the Milky Way passes through Perseus but is mostly obscured by molecular clouds. The constellation's brightest star is the yellow-white supergiant Alpha Persei (also called Mirfak), which shines at magnitude 1.79. It and many of the surrounding stars are members of an open cluster known as the Alpha Persei Cluster. The best-known star, however, is Algol (Beta Persei), linked with ominous legends because of its variability, which is noticeable to the naked eye. Rather than being an intrinsically variable star, it is an eclipsing binary. Other notable star systems in Perseus include X Persei, a binary system containing a neutron star, and GK Persei, a nova that peaked at magnitude 0.2 in 1901. The Double Cluster, comprising two open clusters quite near each other in the sky, was known to the ancient Chinese. The constellation gives its name to the Perseus Cluster (Abell 426), a massive galaxy cluster located 250 million light-years from Earth. It hosts the radiant of the annual Perseids meteor shower—one of the most prominent meteor showers in the sky.