Chapter 30 - Todd County Schools
... • As gravity makes dense regions within a nebula more compact, these regions spin and shrink and begin to form a flattened disk.The disk has a central concentration of matter called a protostar. • The protostar continues to contract and increase in temperature for several million years. Eventually t ...
... • As gravity makes dense regions within a nebula more compact, these regions spin and shrink and begin to form a flattened disk.The disk has a central concentration of matter called a protostar. • The protostar continues to contract and increase in temperature for several million years. Eventually t ...
Standardized Test Prep Chapter 30 Multiple Choice, continued
... • As gravity makes dense regions within a nebula more compact, these regions spin and shrink and begin to form a flattened disk.The disk has a central concentration of matter called a protostar. • The protostar continues to contract and increase in temperature for several million years. Eventually t ...
... • As gravity makes dense regions within a nebula more compact, these regions spin and shrink and begin to form a flattened disk.The disk has a central concentration of matter called a protostar. • The protostar continues to contract and increase in temperature for several million years. Eventually t ...
MOLECULAR OUTFLOWS AND A MID
... Rathborne et al. (2005) identified four clumps in 1.2 mm continuum emission which they named MM1YMM4 (see their Fig. 1). MM1 corresponds to G34.4 MM, MM2 is coincident with the UC H ii region G34.4+0.23, MM3 is about 30 north of G34.4 MM, while MM4 is about 3000 south of the UC H ii region. IRAS 185 ...
... Rathborne et al. (2005) identified four clumps in 1.2 mm continuum emission which they named MM1YMM4 (see their Fig. 1). MM1 corresponds to G34.4 MM, MM2 is coincident with the UC H ii region G34.4+0.23, MM3 is about 30 north of G34.4 MM, while MM4 is about 3000 south of the UC H ii region. IRAS 185 ...
Evidence of suppression of star formation by quasar
... tribution of galaxy colors. If AGN feedback couples to the gas as efficiently as required by galaxy formation models, then massive, early-type galaxies will be gas-poor and passively aging, while younger galaxies, typically lower-mass, late-type galaxies will still have enough star formation materia ...
... tribution of galaxy colors. If AGN feedback couples to the gas as efficiently as required by galaxy formation models, then massive, early-type galaxies will be gas-poor and passively aging, while younger galaxies, typically lower-mass, late-type galaxies will still have enough star formation materia ...
Article PDF - IOPscience
... indicators, the white dwarf population sampled must be as close as possible to being statistically complete. The white dwarf population is composed mainly of lowluminosity stars that are rather difficult to study as we move further away from the Sun. Candidates are mainly discovered from either prop ...
... indicators, the white dwarf population sampled must be as close as possible to being statistically complete. The white dwarf population is composed mainly of lowluminosity stars that are rather difficult to study as we move further away from the Sun. Candidates are mainly discovered from either prop ...
The Life Cycle of Stars: Supernovae in Starbursts by Jason Kezwer
... nuclear background and find an absolute magnitude of MK = −22.19 ± 0.16 (nonabsorbed). This exceeds the luminosity of a typical core collapse supernova by roughly 3.5 magnitudes; rather, the observed variations in nuclear brightness are most likely the signature of an active galactic nucleus embedde ...
... nuclear background and find an absolute magnitude of MK = −22.19 ± 0.16 (nonabsorbed). This exceeds the luminosity of a typical core collapse supernova by roughly 3.5 magnitudes; rather, the observed variations in nuclear brightness are most likely the signature of an active galactic nucleus embedde ...
ASI 2017 Abstract Book - Astronomical Society of India
... Galaxy transformation in the local Universe One of the most outstanding challenges in extragalactic astronomy is to identify the astrophysical processes responsible for transforming simple dark matter haloes into the heterogenous population of galaxies inhabiting today's Universe. How did different ...
... Galaxy transformation in the local Universe One of the most outstanding challenges in extragalactic astronomy is to identify the astrophysical processes responsible for transforming simple dark matter haloes into the heterogenous population of galaxies inhabiting today's Universe. How did different ...
astro-ph/0301519 PDF
... than the values inferred from earlier pure H analyses. In the wider context of white dwarf evolution, we now have the opportunity of comparing the abundances of these very hot objects with their immediate hot white dwarf descendants. To facilitate this, we have re-examined all the archive far UV spe ...
... than the values inferred from earlier pure H analyses. In the wider context of white dwarf evolution, we now have the opportunity of comparing the abundances of these very hot objects with their immediate hot white dwarf descendants. To facilitate this, we have re-examined all the archive far UV spe ...
Galaxy And Mass Assembly (GAMA): Understanding the wavelength
... ellipticals and lenticulars on the Hubble tuning fork diagram (Liller 1966). They have since been referred to as E/S0 galaxies and discy ellipticals (Nieto, Capaccioli & Held 1988; Simien & Michard 1990). This view was later augmented to include parallel sequences for spirals and lenticulars, with ‘ ...
... ellipticals and lenticulars on the Hubble tuning fork diagram (Liller 1966). They have since been referred to as E/S0 galaxies and discy ellipticals (Nieto, Capaccioli & Held 1988; Simien & Michard 1990). This view was later augmented to include parallel sequences for spirals and lenticulars, with ‘ ...
Gamma-Ray Bursts and Puzzles of Core
... observable stellar magnitudes (or with upper R limits) and spectroscopic red shifts against the background of results of the photometric measurement of z applied to galaxies from the Hubble Deep Field (HDF) by Fernández et al. (1999). Circles denote the GRB host galaxies with the BTA photometry, ast ...
... observable stellar magnitudes (or with upper R limits) and spectroscopic red shifts against the background of results of the photometric measurement of z applied to galaxies from the Hubble Deep Field (HDF) by Fernández et al. (1999). Circles denote the GRB host galaxies with the BTA photometry, ast ...
Mapping of the extinction in giant molecular clouds using optical star
... been applied to Schmidt plates during several decades. It consists to count the number of stars by interval of magnitudes (i.e. between m − 1/2 and m + 1/2) in each cell of a regular rectangular grid in an obscured area and to compare the result with the counts obtained in a supposedly unextinguishe ...
... been applied to Schmidt plates during several decades. It consists to count the number of stars by interval of magnitudes (i.e. between m − 1/2 and m + 1/2) in each cell of a regular rectangular grid in an obscured area and to compare the result with the counts obtained in a supposedly unextinguishe ...
Multiplicity in Early Stellar Evolution
... al., 2009) and the number of brown dwarfs formed (e.g., Bonnell et al., 2008; Bate, 2009a,b; Attwood et al., 2009). 3D HD SPH calculations by Bate (2009a) made predictions of the frequency of single, binary, triple and quadruple star systems formed during the collapse of a highly unstable cloud with ...
... al., 2009) and the number of brown dwarfs formed (e.g., Bonnell et al., 2008; Bate, 2009a,b; Attwood et al., 2009). 3D HD SPH calculations by Bate (2009a) made predictions of the frequency of single, binary, triple and quadruple star systems formed during the collapse of a highly unstable cloud with ...
The isotopic mixture of barium in the metal-poor
... occur in the helium and carbon shells of massive stars in their hydrostatic burning phases. The r-process is likely associated with the deep interior of Type II supernovae. Since massive stars dying as Type II supernovae evolve faster than the stars that populate and evolve from the AGB, one anticip ...
... occur in the helium and carbon shells of massive stars in their hydrostatic burning phases. The r-process is likely associated with the deep interior of Type II supernovae. Since massive stars dying as Type II supernovae evolve faster than the stars that populate and evolve from the AGB, one anticip ...
Silicon isotopic abundance toward evolved stars and its application
... the local area and raises the pressure, which initiates an expansion and a series of convective and mixing events (Herwig 2005; Iben & Renzini 1983). During the so-called third dredgeup, the products of He burning and the s-process elements are brought to the surface, e.g., 12 C, which can lead to t ...
... the local area and raises the pressure, which initiates an expansion and a series of convective and mixing events (Herwig 2005; Iben & Renzini 1983). During the so-called third dredgeup, the products of He burning and the s-process elements are brought to the surface, e.g., 12 C, which can lead to t ...
The recent star-formation history of the Large and Small Magellanic
... concluded that field and cluster star-formation modes are tightly coupled. They found a quiescent epoch from 12 to 5 Gyr ago and star-formation peaks at 2 Gyr, 500 Myr, 100 Myr, and 12 Myr. The study of the spatial distribution of clusters as well as starformation rates are also equally interesting. ...
... concluded that field and cluster star-formation modes are tightly coupled. They found a quiescent epoch from 12 to 5 Gyr ago and star-formation peaks at 2 Gyr, 500 Myr, 100 Myr, and 12 Myr. The study of the spatial distribution of clusters as well as starformation rates are also equally interesting. ...
2 The Concept of “Spectral Classes”
... becomes a group containing as few as one member. There were two general problems that prevented the IUE Object Class system from succeeding and thereby preventing archival data users from conveniently retrieving archival information on groups of stars with common properties. One was that owing to it ...
... becomes a group containing as few as one member. There were two general problems that prevented the IUE Object Class system from succeeding and thereby preventing archival data users from conveniently retrieving archival information on groups of stars with common properties. One was that owing to it ...
Stellarium User Guide - Skolekonsulenterne.dk
... also notice that the stars have started to move slightly across the sky. If it’s daytime you might be able to see the sun moving (but it’s less apparent than the movement of the stars). Increase the rate at which time passes again by clicking on the button a third time. Now time is really flying! Le ...
... also notice that the stars have started to move slightly across the sky. If it’s daytime you might be able to see the sun moving (but it’s less apparent than the movement of the stars). Increase the rate at which time passes again by clicking on the button a third time. Now time is really flying! Le ...
The Relation between Interstellar Turbulence and Star Formation
... of radiation, with competition only from the 3K Since about a century ago we know that these black body radiation of the cosmic microwave clouds are associated with the birth of stars. The background and from accretion processes onto advent of new observational instruments and black holes in active ...
... of radiation, with competition only from the 3K Since about a century ago we know that these black body radiation of the cosmic microwave clouds are associated with the birth of stars. The background and from accretion processes onto advent of new observational instruments and black holes in active ...
CONSTELLATION PERSEUS The constellation
... Located 92.8 light-years from Earth, it varies in apparent magnitude from a minimum of 3.5 to a maximum of 2.3 over a period of 2.867 days. The star system is the prototype of a group of eclipsing binary stars named Algol variables. • Alpha Persei known as Mirfak (Arabic for elbow) is the brightest ...
... Located 92.8 light-years from Earth, it varies in apparent magnitude from a minimum of 3.5 to a maximum of 2.3 over a period of 2.867 days. The star system is the prototype of a group of eclipsing binary stars named Algol variables. • Alpha Persei known as Mirfak (Arabic for elbow) is the brightest ...
Circumstellar Material in Young Stellar Objects
... high luminosity. The first one to incorporate the physics of cloud collapse into a numerical evolution code was Shu (1977), who showed that it would start in the cloud center and work from the inside-out, due to the limited sound speed in the cloud. The timescale for this collapse would be determine ...
... high luminosity. The first one to incorporate the physics of cloud collapse into a numerical evolution code was Shu (1977), who showed that it would start in the cloud center and work from the inside-out, due to the limited sound speed in the cloud. The timescale for this collapse would be determine ...
THE UV-OPTICAL COLOR MAGNITUDE DIAGRAM. II. PHYSICAL
... We use the UV-optical color magnitude diagram in combination with spectroscopic and photometric measurements derived from the SDSS spectroscopic sample to measure the distribution of galaxies in the local universe (z < 0:25) and their physical properties as a function of specific star formation rate ...
... We use the UV-optical color magnitude diagram in combination with spectroscopic and photometric measurements derived from the SDSS spectroscopic sample to measure the distribution of galaxies in the local universe (z < 0:25) and their physical properties as a function of specific star formation rate ...
2 Statistical properties of a sample of periodically variable B-type supergiants
... chapter contains a follow-up study of the latter sample. Our goal is to evaluate the suggestion by Waelkens et al. (1998) that these periodically variable B-type supergiants experience oscillations excited by the opacity mechanism, in analogy to main sequence B stars. The suggestion of the occurrenc ...
... chapter contains a follow-up study of the latter sample. Our goal is to evaluate the suggestion by Waelkens et al. (1998) that these periodically variable B-type supergiants experience oscillations excited by the opacity mechanism, in analogy to main sequence B stars. The suggestion of the occurrenc ...
Starspots: A Key to the Stellar Dynamo | SpringerLink
... The multitude of activity phenomena on the Sun are related to magnetic fields which are generated by cyclonic turbulence in the outer convection zone and penetrate the solar atmosphere forming sunspots, plages, network, etc. They further expand into the outer atmosphere and exhibit themselves as hig ...
... The multitude of activity phenomena on the Sun are related to magnetic fields which are generated by cyclonic turbulence in the outer convection zone and penetrate the solar atmosphere forming sunspots, plages, network, etc. They further expand into the outer atmosphere and exhibit themselves as hig ...
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.