![Deep HST Imaging of M33: Reliability and Recovery of the Star](http://s1.studyres.com/store/data/005809706_1-39438454d072732f4a3a34ff7bf913bb-300x300.png)
Deep HST Imaging of M33: Reliability and Recovery of the Star
... • Integrated SFH is not exponentially declining, SFR has been roughly constant, or even increased in past several Gyr ...
... • Integrated SFH is not exponentially declining, SFR has been roughly constant, or even increased in past several Gyr ...
Exploring the Helium Reionization Era
... subatomic particles as the universe expanded and cooled. Among these particles were abundant free electrons, which easily scattered light’s photons, making this early epoch look like an opaque fog. After about 400,000 years, the universe cooled to the point where the electrons could combine with pro ...
... subatomic particles as the universe expanded and cooled. Among these particles were abundant free electrons, which easily scattered light’s photons, making this early epoch look like an opaque fog. After about 400,000 years, the universe cooled to the point where the electrons could combine with pro ...
Planet formation around M-dwarfs: the moving snow line and super
... To reach isolation, protoplanets must overcome type I migration, where the object is torqued by density waves excited in the gas disk (e.g. Tanaka et al. 2002). Type I migration timescales are typically very short—of the order 104 yr for the Jovian core. Icy protoplanets in general may suffer simila ...
... To reach isolation, protoplanets must overcome type I migration, where the object is torqued by density waves excited in the gas disk (e.g. Tanaka et al. 2002). Type I migration timescales are typically very short—of the order 104 yr for the Jovian core. Icy protoplanets in general may suffer simila ...
ppt - SLAC
... powerful stellar wind. Wolf-Rayets are believed to be O stars that have lost their hydrogen envelopes, leaving their helium cores exposed, often in a binary system, and that are doomed, within a few million years, to explode as Type Ib or Ic supernovae. There are two spectral subclasses of Wolf-Raye ...
... powerful stellar wind. Wolf-Rayets are believed to be O stars that have lost their hydrogen envelopes, leaving their helium cores exposed, often in a binary system, and that are doomed, within a few million years, to explode as Type Ib or Ic supernovae. There are two spectral subclasses of Wolf-Raye ...
Overview Evolution of massive stars Evolution of massive stars
... shock. This is poorly understood and an active area of research. Eventually shock overcomes material falling inward: explosion – Supernova! ...
... shock. This is poorly understood and an active area of research. Eventually shock overcomes material falling inward: explosion – Supernova! ...
Massive star formation in 100000 years from turbulent and
... rate of the star; the value of the former quantity is currently uncertain by many orders of magnitude1,2,3,4,5,6 , leading to other astrophysical questions. For example, the variation of t∗f with stellar mass dictates whether massive stars can form simultaneously with low-mass stars in clusters. Her ...
... rate of the star; the value of the former quantity is currently uncertain by many orders of magnitude1,2,3,4,5,6 , leading to other astrophysical questions. For example, the variation of t∗f with stellar mass dictates whether massive stars can form simultaneously with low-mass stars in clusters. Her ...
lec-life-main-sequen..
... no longer balance in the layers of the star, and the layers begin to expand or contract quickly, then the star has left the main sequence. This is Eta Carinae, where in at least one shell, on at least one occasion, pressure won. In other stars, self-gravity wins. ...
... no longer balance in the layers of the star, and the layers begin to expand or contract quickly, then the star has left the main sequence. This is Eta Carinae, where in at least one shell, on at least one occasion, pressure won. In other stars, self-gravity wins. ...
Origin of close binary systems
... --------------1) Some of the most exciting cosmic phenemena due to the presence of massive close binaries 2) Studies of star forming regions & young clusters allow us to observe binary parameter distributions give extra info on massive star formation provide I.C. for models of interacting binary evo ...
... --------------1) Some of the most exciting cosmic phenemena due to the presence of massive close binaries 2) Studies of star forming regions & young clusters allow us to observe binary parameter distributions give extra info on massive star formation provide I.C. for models of interacting binary evo ...
1_Introduction
... If you know the luminosity L, and you measure the flux f, you can compute the distance r: ...
... If you know the luminosity L, and you measure the flux f, you can compute the distance r: ...
Autumn Night sky Guide
... responds well to high power in a telescope. M15 has the distinction of containing the first planetary nebula to be discovered in a globular cluster, Pease 1. Don’t expect to be able to see it though. M31 – the Andromeda Galaxy M31 is a spiral galaxy very similar but rather larger than our Milky Way. ...
... responds well to high power in a telescope. M15 has the distinction of containing the first planetary nebula to be discovered in a globular cluster, Pease 1. Don’t expect to be able to see it though. M31 – the Andromeda Galaxy M31 is a spiral galaxy very similar but rather larger than our Milky Way. ...
Lecture20
... Newer stars have 1% - 4% heavier elements Old stars have 1/10 to 1/100 as many heavier elements as the Sun ...
... Newer stars have 1% - 4% heavier elements Old stars have 1/10 to 1/100 as many heavier elements as the Sun ...
Formation of Solar System
... – Dense clouds litter the galaxy – Low temperature (10 K) – High density (1000 to 1 million times greater than interstellar medium) – Rich collection of molecules (but mostly H) – 1015 km in diameter – 2000 or so in Milky Way – Favorable places for star formation (and, therefore, perhaps planetary f ...
... – Dense clouds litter the galaxy – Low temperature (10 K) – High density (1000 to 1 million times greater than interstellar medium) – Rich collection of molecules (but mostly H) – 1015 km in diameter – 2000 or so in Milky Way – Favorable places for star formation (and, therefore, perhaps planetary f ...
vuorinen_neutron_stars
... 2. but not impossible if you systematically use 1st principles results at low and high density 3. Discovering massive stars places strong constraints on nuclear matter EoS due to tension with soft pQCD pressure 4. pQCD constraint useful even if no quark matter present in stars ...
... 2. but not impossible if you systematically use 1st principles results at low and high density 3. Discovering massive stars places strong constraints on nuclear matter EoS due to tension with soft pQCD pressure 4. pQCD constraint useful even if no quark matter present in stars ...
Study Guide for the Final Exam
... The mass of a star determines the size of its Roche Lobe - which can be teardrop-shaped for binary stars. Note that these are very important in our understanding of Supernovas and other phenomena! Sometimes what remains collapses into a hot, dense ball of non-fusible material collectively called a W ...
... The mass of a star determines the size of its Roche Lobe - which can be teardrop-shaped for binary stars. Note that these are very important in our understanding of Supernovas and other phenomena! Sometimes what remains collapses into a hot, dense ball of non-fusible material collectively called a W ...
ppt - ciera
... Chandra and XMM fields reveals no new 530 s pulsars, so there is a <0.5% chance of finding a magnetar in any field (Nechita, Gaensler, Muno, et al. in prep). • The pulsar is well within the cluster, with a <10% chance of being an unrelated X-ray source. ...
... Chandra and XMM fields reveals no new 530 s pulsars, so there is a <0.5% chance of finding a magnetar in any field (Nechita, Gaensler, Muno, et al. in prep). • The pulsar is well within the cluster, with a <10% chance of being an unrelated X-ray source. ...
Astronomy 104: Stellar Astronomy
... Where the Elements came from? • Big Bang made 75% H, 25% He – stars make everything else! ...
... Where the Elements came from? • Big Bang made 75% H, 25% He – stars make everything else! ...
Two extremely luminous WN stars in the Galactic center with
... λ 2.189 μm feature cannot be due to He ii emission from that star. Therefore we chose as our best-fitting model the grid point that lies closest to the intersection point of the contours for the strong He i λ2.06 μm and He i λ2.115 μm lines. The parameters are T ∗ = 25.1 kK and log Rt = 1.48 (large ...
... λ 2.189 μm feature cannot be due to He ii emission from that star. Therefore we chose as our best-fitting model the grid point that lies closest to the intersection point of the contours for the strong He i λ2.06 μm and He i λ2.115 μm lines. The parameters are T ∗ = 25.1 kK and log Rt = 1.48 (large ...
Galaxies - Stockton University
... interstellar extinction is very significant. This has the effect of making the distribution of stars appear more centered upon us than it really is (Kapteyn's model) as well as rather small. At the same time, it makes the globular clusters appear fainter and more distant so makes Shapley's model too ...
... interstellar extinction is very significant. This has the effect of making the distribution of stars appear more centered upon us than it really is (Kapteyn's model) as well as rather small. At the same time, it makes the globular clusters appear fainter and more distant so makes Shapley's model too ...
Review for Astronomy 3 Midterm #2
... -- First, a supernova shock will perturb a cloud and cause it to begin collapsing. -- The cloud will break into fragments that continue to collapse, and those fragments in turn will break into smaller fragments, and so on, until they are the right size for forming a star -- Nuclear burning starts as ...
... -- First, a supernova shock will perturb a cloud and cause it to begin collapsing. -- The cloud will break into fragments that continue to collapse, and those fragments in turn will break into smaller fragments, and so on, until they are the right size for forming a star -- Nuclear burning starts as ...
Classifying Stellar Spectra
... We have learned that astronomers classify stars by their spectra. The particular spectral class of a star tells us the star's surface temperature. In this activity, you will take part in a project called Stellar Classification Online Public Exploration (SCOPE). Follow the directions below to take pa ...
... We have learned that astronomers classify stars by their spectra. The particular spectral class of a star tells us the star's surface temperature. In this activity, you will take part in a project called Stellar Classification Online Public Exploration (SCOPE). Follow the directions below to take pa ...
Xtra_credit_MC_chapt_10−12_2014.txt Xtra_credit_MC_chapt_10
... 1) In the video at the instant of the first appearance of the Sun on the eastern horizon (called dawn) then the video says to look in the sky: a) just above the sun b) straight up (at 90−degrees from the direction to the sun) c) directly opposite the sun (at 180−degrees from the sun) d) a) or c) dep ...
... 1) In the video at the instant of the first appearance of the Sun on the eastern horizon (called dawn) then the video says to look in the sky: a) just above the sun b) straight up (at 90−degrees from the direction to the sun) c) directly opposite the sun (at 180−degrees from the sun) d) a) or c) dep ...
Stellar Temperatures
... Stellar temperatures range from ~3000 K to ~100,000 K (although there are exceptions). To zeroth order, they can be considered blackbodies, with stellar absorption lines on top. There is a great variety of stellar absorption lines; the strength of any individual line is determined by the star’s • T ...
... Stellar temperatures range from ~3000 K to ~100,000 K (although there are exceptions). To zeroth order, they can be considered blackbodies, with stellar absorption lines on top. There is a great variety of stellar absorption lines; the strength of any individual line is determined by the star’s • T ...
Science Implications of Various Servicing Options
... • Distant objects move away from us faster than nearby objects. • As a result, distant objects appear redder than they would if they were nearby - they are redshifted. ...
... • Distant objects move away from us faster than nearby objects. • As a result, distant objects appear redder than they would if they were nearby - they are redshifted. ...
S E D
... The Sun is our closest star with a mass of 1 solar mass, or ~2*1030kg. The mass of it, categorizes it under the lower mass stars. It has a very long timescale, 1010years, and an convective envelope. All our fundamental equations are all a result from the measurements to the sun; T, P, p, f(frequency ...
... The Sun is our closest star with a mass of 1 solar mass, or ~2*1030kg. The mass of it, categorizes it under the lower mass stars. It has a very long timescale, 1010years, and an convective envelope. All our fundamental equations are all a result from the measurements to the sun; T, P, p, f(frequency ...
observational requirements, feasability, expectations
... Need for a precise correction of very low frequency instrumental noise!! Good to have ground observations to have Ca H & K measurements (Mt Wilson index) ...
... Need for a precise correction of very low frequency instrumental noise!! Good to have ground observations to have Ca H & K measurements (Mt Wilson index) ...
Planetary nebula
![](https://commons.wikimedia.org/wiki/Special:FilePath/NGC6543.jpg?width=300)
A planetary nebula, often abbreviated as PN or plural PNe, is a kind of emission nebula consisting of an expanding glowing shell of ionized gas ejected from old red giant stars late in their lives. The word ""nebula"" is Latin for mist or cloud and the term ""planetary nebula"" is a misnomer that originated in the 1780s with astronomer William Herschel because when viewed through his telescope, these objects appeared to him to resemble the rounded shapes of planets. Herschel's name for these objects was popularly adopted and has not been changed. They are a relatively short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years.A mechanism for formation of most planetary nebulae is thought to be the following: at the end of the star's life, during the red giant phase, the outer layers of the star are expelled by strong stellar winds. Eventually, after most of the red giant's atmosphere is dissipated, the exposed hot, luminous core emits ultraviolet radiation to ionize the ejected outer layers of the star. Absorbed ultraviolet light energises the shell of nebulous gas around the central star, appearing as a bright coloured planetary nebula at several discrete visible wavelengths.Planetary nebulae may play a crucial role in the chemical evolution of the Milky Way, returning material to the interstellar medium from stars where elements, the products of nucleosynthesis (such as carbon, nitrogen, oxygen and neon), have been created. Planetary nebulae are also observed in more distant galaxies, yielding useful information about their chemical abundances.In recent years, Hubble Space Telescope images have revealed many planetary nebulae to have extremely complex and varied morphologies. About one-fifth are roughly spherical, but the majority are not spherically symmetric. The mechanisms which produce such a wide variety of shapes and features are not yet well understood, but binary central stars, stellar winds and magnetic fields may play a role.