The Ionized Nebula surrounding the Red Supergiant W26 in
... previous RSG phase (e.g., Smartt et al. 2002) and the detection of similar structures around a RSG might help resolve this. While Sher 25 does have two polar outflows, one side is notably brighter than the other, which might suggest that a second outflow exists around W26 but is not detected. Altern ...
... previous RSG phase (e.g., Smartt et al. 2002) and the detection of similar structures around a RSG might help resolve this. While Sher 25 does have two polar outflows, one side is notably brighter than the other, which might suggest that a second outflow exists around W26 but is not detected. Altern ...
minnesota
... 1) Metal deficient stars are a marvelous laboratory for studying nucleosynthesis in massive stars. Their nucleosynthesis is relatively uncontaminated by other sources. 2) Especially because of their reduced mass loss, low metallicity (very) massive stars have different properties when they die and p ...
... 1) Metal deficient stars are a marvelous laboratory for studying nucleosynthesis in massive stars. Their nucleosynthesis is relatively uncontaminated by other sources. 2) Especially because of their reduced mass loss, low metallicity (very) massive stars have different properties when they die and p ...
The Solar Nebula - Lincoln-Sudbury Regional High School
... Giant molecular clouds are extremely cold – only a few degrees warmer than the near-zero of space – and rotate very slowly. So at some stage gravity actually wins and the giant molecular cloud begins to collapse under its own gravity. The giant molecular cloud fragments, forming much smaller dense c ...
... Giant molecular clouds are extremely cold – only a few degrees warmer than the near-zero of space – and rotate very slowly. So at some stage gravity actually wins and the giant molecular cloud begins to collapse under its own gravity. The giant molecular cloud fragments, forming much smaller dense c ...
CAN COMBINATION OF `KOZAI EFFECT` AND TIDAL FRICTION
... In binary stars, tidal friction dissipates a fraction of the orbital energy at constant angular momentum and will circularise binary orbits on a rather short timescale compared with the nuclear timescale, provided that at least one star of the binary has a radius comparable to the separation between ...
... In binary stars, tidal friction dissipates a fraction of the orbital energy at constant angular momentum and will circularise binary orbits on a rather short timescale compared with the nuclear timescale, provided that at least one star of the binary has a radius comparable to the separation between ...
Misc-ReviewForAstroTest
... nuclei cannot exist. 6. The outer envelope is about a mile thick - a crust of nuclei and electrons. 7. The core is a super-fluid. ...
... nuclei cannot exist. 6. The outer envelope is about a mile thick - a crust of nuclei and electrons. 7. The core is a super-fluid. ...
Debris Disks with ALMA
... where planet formation got started – perturbations of dust disks indicate where distant giant planets are located – seen around main-sequence stars of any age ...
... where planet formation got started – perturbations of dust disks indicate where distant giant planets are located – seen around main-sequence stars of any age ...
Lecture 24: High Mass Star Formation Astro 6890/8980 Prof. Tom
... with a disk. Must overcome magnetic pressure, resulting in magnetospheric accretion for low mass stars. Must overcome photon pressure for high mass stars. ...
... with a disk. Must overcome magnetic pressure, resulting in magnetospheric accretion for low mass stars. Must overcome photon pressure for high mass stars. ...
galaxy phenomenology
... ‣ most massive gravitational bound objects in the Universe ‣ contain up to thousands of galaxies ‣ most baryons intracluster gas, T~107-108 K gas ‣ smaller collections of bound galaxies are called 'groups' ...
... ‣ most massive gravitational bound objects in the Universe ‣ contain up to thousands of galaxies ‣ most baryons intracluster gas, T~107-108 K gas ‣ smaller collections of bound galaxies are called 'groups' ...
The light curves for a nova look like the following.
... In this process the capture of neutrons happens in such a dense environment that the unstable isotopes do not have time to decay. The high density of neutrons needed is only found during a supernova explosion and, thus, all the heavy elements in the Universe (radium, uranium and plutonium) are produ ...
... In this process the capture of neutrons happens in such a dense environment that the unstable isotopes do not have time to decay. The high density of neutrons needed is only found during a supernova explosion and, thus, all the heavy elements in the Universe (radium, uranium and plutonium) are produ ...
2002 astronomy magazine index
... MCG-6-30-15 (spiral galaxy), 2:26 Mercury, 10:40–46 Messier Marathons, 3:64–71 Messier objects, viewing other objects near, 7:52–55 meteors and meteorites collision with Earth, 3:82–83 on Moon, from Earth, 11:28 Microscopium (constellation), 8:68–72 Milky Way Galaxy burst of star formation expected, ...
... MCG-6-30-15 (spiral galaxy), 2:26 Mercury, 10:40–46 Messier Marathons, 3:64–71 Messier objects, viewing other objects near, 7:52–55 meteors and meteorites collision with Earth, 3:82–83 on Moon, from Earth, 11:28 Microscopium (constellation), 8:68–72 Milky Way Galaxy burst of star formation expected, ...
T Tauri Variable Type Star
... Pre Main Sequence – young, low mass stars that are contracting as they evolve toward their main sequence stage. Mostly made of Hydrogen, some Helium, and some trace elements. Of the trace elements, Lithium appears which is an indicator of stellar youth. Often have large protoplanetary accretion disk ...
... Pre Main Sequence – young, low mass stars that are contracting as they evolve toward their main sequence stage. Mostly made of Hydrogen, some Helium, and some trace elements. Of the trace elements, Lithium appears which is an indicator of stellar youth. Often have large protoplanetary accretion disk ...
Cepheid variable stars
... Pulsating stars are a type of variable star in which brightness variations are caused by changes in the area and temperature of the star’s surface layers. Recent evidence suggests that all stars pulsate (if we measure them carefully enough), although the presence of concentrated populations of pulsa ...
... Pulsating stars are a type of variable star in which brightness variations are caused by changes in the area and temperature of the star’s surface layers. Recent evidence suggests that all stars pulsate (if we measure them carefully enough), although the presence of concentrated populations of pulsa ...
Ментальные карты нашей цивилизации в сознании эпохи
... In view of the aforesaid it is possible to tell (certainly, with the certain clauses), that at mapping extraterrestrial territories we directly reproduce space of geographical images on a map. Топонимы planetary objects, on the one hand, being carriers of images of in honour of whom them have approp ...
... In view of the aforesaid it is possible to tell (certainly, with the certain clauses), that at mapping extraterrestrial territories we directly reproduce space of geographical images on a map. Топонимы planetary objects, on the one hand, being carriers of images of in honour of whom them have approp ...
Photometric Mass-to-Light Ratio In addition to a population`s total
... Numerically, this works out to a mass loss rate of ∼ 0.02M¯ per Gigayear per unit solar luminosity for an old stellar population that is 1010 years old. When integrated over the lifetime of a galaxy, the result is that ∼ 15% of the original mass will be lost from stars during a Hubble time. ...
... Numerically, this works out to a mass loss rate of ∼ 0.02M¯ per Gigayear per unit solar luminosity for an old stellar population that is 1010 years old. When integrated over the lifetime of a galaxy, the result is that ∼ 15% of the original mass will be lost from stars during a Hubble time. ...
Lecture 21
... zone becomes more transparent, absorbs less energy => weight from higher layers pushes it back inward. => Contraction. Upon compression, partial He ionization zone becomes more opaque again, absorbs more energy than needed for equilibrium => Expansion ...
... zone becomes more transparent, absorbs less energy => weight from higher layers pushes it back inward. => Contraction. Upon compression, partial He ionization zone becomes more opaque again, absorbs more energy than needed for equilibrium => Expansion ...
Stellar populations and dynamics in the Milky Way galaxy
... galaxies are cold, with T Tvirial, energy must have been lost. Since this lost energy was in random motions of individual particles, the only possible loss mechanism is through an inelastic collision, leading to the internal excitation of the particles, and subsequent energy loss through radiative ...
... galaxies are cold, with T Tvirial, energy must have been lost. Since this lost energy was in random motions of individual particles, the only possible loss mechanism is through an inelastic collision, leading to the internal excitation of the particles, and subsequent energy loss through radiative ...
PowerPoint
... High-mass star forming regions are much more distant (in average) than those of low-mass stars (high-mass: 3-7kpc vs. low-mass: 0.1-0.3 kpc) OB stars - form preferentially in the centre of dense star clusters - seem to live pref. in (tight) binary and higher order systems ...
... High-mass star forming regions are much more distant (in average) than those of low-mass stars (high-mass: 3-7kpc vs. low-mass: 0.1-0.3 kpc) OB stars - form preferentially in the centre of dense star clusters - seem to live pref. in (tight) binary and higher order systems ...
SALT Science – UW Madison
... These line profiles were observed for the recurrent nova T Pyx a year and a half after the outburst. Nebular [O III] lines at 5007 Å were still very strong and confirmed a bipolar mass ejection. There seem to be two distincts region of emission, both asymmetric. The He II emission line at 4686 Å, mu ...
... These line profiles were observed for the recurrent nova T Pyx a year and a half after the outburst. Nebular [O III] lines at 5007 Å were still very strong and confirmed a bipolar mass ejection. There seem to be two distincts region of emission, both asymmetric. The He II emission line at 4686 Å, mu ...
journey to the stars - American Museum of Natural History
... heated this pocket within its birth cloud. If we speed up time, we can see the intense light of these bright stars driving the cloud away, revealing the stars within. Bright stars are bright because they’re massive and hot. Mass is how much stuff there is in something. The brightest, most massive st ...
... heated this pocket within its birth cloud. If we speed up time, we can see the intense light of these bright stars driving the cloud away, revealing the stars within. Bright stars are bright because they’re massive and hot. Mass is how much stuff there is in something. The brightest, most massive st ...
the chromospheres of classical cepheids. 111. a search for transition
... short ( < 1 hr). While emission was seen in most of the stars, in the shortest period star, 6 Cep, little significant emission was found. The upper limits we were able to place on the fluxes were, however, larger than the expected values based on the other Cepheids and on nonvariables. In order to d ...
... short ( < 1 hr). While emission was seen in most of the stars, in the shortest period star, 6 Cep, little significant emission was found. The upper limits we were able to place on the fluxes were, however, larger than the expected values based on the other Cepheids and on nonvariables. In order to d ...
Stellar Evolution
... The Period-Luminosity Relation The variability period P of a Cepheid variable is positively correlated with its luminosity: ...
... The Period-Luminosity Relation The variability period P of a Cepheid variable is positively correlated with its luminosity: ...
the Scientia Review
... the universe was created. Scientists cannot prove that the universe was created this way, but the vast majority accept the Big Bang. They also do not know what was there before the universe was made, or if there really was anything at all. The Big Bang Theory says that our universe started out as an ...
... the universe was created. Scientists cannot prove that the universe was created this way, but the vast majority accept the Big Bang. They also do not know what was there before the universe was made, or if there really was anything at all. The Big Bang Theory says that our universe started out as an ...
Slide 1
... -A final decision on the appropriate criteria for data selection (that is, the separation of the data into four regions of interest for fitting) will need to be made. -Since the data represents a two dimensional surface rather than a curve when the mass is not held constant, a multivariable fit will ...
... -A final decision on the appropriate criteria for data selection (that is, the separation of the data into four regions of interest for fitting) will need to be made. -Since the data represents a two dimensional surface rather than a curve when the mass is not held constant, a multivariable fit will ...
SN 2004dj
... Garnett et al. (1997) measured the metallity and its radial distribution in NGC 2403 ...
... Garnett et al. (1997) measured the metallity and its radial distribution in NGC 2403 ...
Planetary nebula
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.