![The Local Bubble](http://s1.studyres.com/store/data/007879782_2-18cb85e9dc0dfc0f2790c1c3a589b79f-300x300.png)
The Local Bubble
... • EVAF: 3D parallelized adaptive mesh refinement (AMR) hydrocode [details in de Avillez & Breitschwerdt (2004, 2005)] • Solves full HD/MHD equations on large domain: 1 kpc × 1 kpc × ±10 kpc ...
... • EVAF: 3D parallelized adaptive mesh refinement (AMR) hydrocode [details in de Avillez & Breitschwerdt (2004, 2005)] • Solves full HD/MHD equations on large domain: 1 kpc × 1 kpc × ±10 kpc ...
Planet Formation and Evolution: The Solar System and Extrasolar
... The TCfA Transit Timing Survey On the origin of eccentricities among extrasolar planets H2 emission in the disk of HD97048 Precision Astrometry from Images Obtained with Adaptive Optics A dynamical analysis of the multiple planetary system of HR 8799 Planetary population synthesis: Correlations betw ...
... The TCfA Transit Timing Survey On the origin of eccentricities among extrasolar planets H2 emission in the disk of HD97048 Precision Astrometry from Images Obtained with Adaptive Optics A dynamical analysis of the multiple planetary system of HR 8799 Planetary population synthesis: Correlations betw ...
ppt
... – Spectrophotometry in the SDSS galaxies have been improved by a factor of 5 for the repeated observations. – Modeling of QSO continuum and line kinematics. – We demonstrate the importance of sampling the full probability distribution of parameters in the stellar population synthesis modeling of gal ...
... – Spectrophotometry in the SDSS galaxies have been improved by a factor of 5 for the repeated observations. – Modeling of QSO continuum and line kinematics. – We demonstrate the importance of sampling the full probability distribution of parameters in the stellar population synthesis modeling of gal ...
SHELL BURNING STARS: Red Giants and Red Supergiants
... composition. For example, the core may have no hydrogen, and mostly helium, while the envelope may be hydrogen rich. As a result, there is a nuclear burning shell at the bottom of the envelope; hydrogen burning shell in our example. The heat generated in the shell is diffusing out with radiation, an ...
... composition. For example, the core may have no hydrogen, and mostly helium, while the envelope may be hydrogen rich. As a result, there is a nuclear burning shell at the bottom of the envelope; hydrogen burning shell in our example. The heat generated in the shell is diffusing out with radiation, an ...
The Milky Way galaxy Contents Summary
... stars move on nearly circular orbits around the centre and never go far from the system’s equatorial plane. The morphological type of a galaxy is determined by the relative contributions of these two components to the system’s total luminosity. Early-type galaxies are dominated by their spheroids: i ...
... stars move on nearly circular orbits around the centre and never go far from the system’s equatorial plane. The morphological type of a galaxy is determined by the relative contributions of these two components to the system’s total luminosity. Early-type galaxies are dominated by their spheroids: i ...
What makes a planet habitable? - INAF
... The outer edge of the HZ is the distance from the star where a maximum greenhouse effect fails to keep the surface of the planet above the freezing point, or the distance from the star where CO2 starts condensing (Kasting et al. 1993). On an Earth-like planet where the carbonate–silicate cycle is at ...
... The outer edge of the HZ is the distance from the star where a maximum greenhouse effect fails to keep the surface of the planet above the freezing point, or the distance from the star where CO2 starts condensing (Kasting et al. 1993). On an Earth-like planet where the carbonate–silicate cycle is at ...
Document
... • The sun is not powered by cooling! • Nuclear fusion – We understand the physics of this very well indeed • We can create fusion reactions on Earth! • We can measure the sun’s energy output • We know the processes causing this • We know how much fuel the sun has ...
... • The sun is not powered by cooling! • Nuclear fusion – We understand the physics of this very well indeed • We can create fusion reactions on Earth! • We can measure the sun’s energy output • We know the processes causing this • We know how much fuel the sun has ...
spectral typing of late-type stellar companions to young stars
... of the SRF rather than the true spectra of the primary causes a small error. There are two components of this error. One is that there may be an error in the reported spectral type of the primary; it may be either later or earlier than what we use. On most stars, the difference between various deter ...
... of the SRF rather than the true spectra of the primary causes a small error. There are two components of this error. One is that there may be an error in the reported spectral type of the primary; it may be either later or earlier than what we use. On most stars, the difference between various deter ...
Red Giant Branch
... Fraction of the element Si condensed into forsterite grains on the tip of the RGB, with maximum possible growth coefficient. ...
... Fraction of the element Si condensed into forsterite grains on the tip of the RGB, with maximum possible growth coefficient. ...
Indroduction
... star forming medium (Padoan et al., 1997), which is likely to vary with galaxy mass. In regard to the second alternative, it is worth recalling that the mean lifetime of a binary system (Type Ia progenitors) is 1 Gyr, and therefore the contamination by Type Ia supernov occurs later as compared to ...
... star forming medium (Padoan et al., 1997), which is likely to vary with galaxy mass. In regard to the second alternative, it is worth recalling that the mean lifetime of a binary system (Type Ia progenitors) is 1 Gyr, and therefore the contamination by Type Ia supernov occurs later as compared to ...
Visible neutral helium lines in main sequence B-type stars
... The agreement is closer than Auer & Mihalas presumably because of the use of more realistic model atmospheres as far as line-blanketing is concerned and of more accurate transition probabilities. At the highest temperatures, observed EW’s of Hei 412.1 nm line are larger than computed because of the ...
... The agreement is closer than Auer & Mihalas presumably because of the use of more realistic model atmospheres as far as line-blanketing is concerned and of more accurate transition probabilities. At the highest temperatures, observed EW’s of Hei 412.1 nm line are larger than computed because of the ...
Winds of Main-Sequence Stars - Harvard
... The solar wind mass los rate • The sphere-averaged “M” isn’t usually considered by solar physicists! • Wang (1998, CS10) used empirical relationships between B-field, wind speed, and density to reconstruct M over two solar cycles. ...
... The solar wind mass los rate • The sphere-averaged “M” isn’t usually considered by solar physicists! • Wang (1998, CS10) used empirical relationships between B-field, wind speed, and density to reconstruct M over two solar cycles. ...
Astrophysical false positives in direct imaging for exoplanets: a white
... composed of 12 acquisitions on the source with small dithering and one acquisition on the sky. Immediately after observing our science targets, we observed the standard star HIP 17280 (B5V) following an AB pattern to correct our spectra for telluric features. HD 8049 and the standard were both obser ...
... composed of 12 acquisitions on the source with small dithering and one acquisition on the sky. Immediately after observing our science targets, we observed the standard star HIP 17280 (B5V) following an AB pattern to correct our spectra for telluric features. HD 8049 and the standard were both obser ...
The Eight Parts of Speech:
... The word altruism (AL-troo-izm) contains the Latin stems alter (other) and ism (doctrine). Altruism is the opposite of selfishness and egocentrism; it is the ability to do things that are selfless, out of a genuine concern for others or for the common good. In James Joyce’s A Portrait of the Artist ...
... The word altruism (AL-troo-izm) contains the Latin stems alter (other) and ism (doctrine). Altruism is the opposite of selfishness and egocentrism; it is the ability to do things that are selfless, out of a genuine concern for others or for the common good. In James Joyce’s A Portrait of the Artist ...
Supervisors
... The atmospheres of very hot stars cannot be assumed to be in LTE and non-LTE (NLTE) must be used (Przybilla et al., 2011). This is because of the general properties of stellar plasma. In the case of equal pressures hotter plasma has lower density than colder plasma. Lower density means less collisio ...
... The atmospheres of very hot stars cannot be assumed to be in LTE and non-LTE (NLTE) must be used (Przybilla et al., 2011). This is because of the general properties of stellar plasma. In the case of equal pressures hotter plasma has lower density than colder plasma. Lower density means less collisio ...
Forming Jupiter, Saturn, Uranus and Neptune in Few Million Years
... we consider that most of the planetesimal mass lies in kilometer-sized bodies, the formation time of the ice giants results much longer than the estimated lifetime of the protoplanetary disk. In order to evaluate the effects of the above mentioned inhibition on the solids accretion rate, we also com ...
... we consider that most of the planetesimal mass lies in kilometer-sized bodies, the formation time of the ice giants results much longer than the estimated lifetime of the protoplanetary disk. In order to evaluate the effects of the above mentioned inhibition on the solids accretion rate, we also com ...
Magnetic susceptibility, magnetization, magnetic moment and
... some cases, intensity ratios are very sensitive to both T e and ne . In this case, two or more diagnostics must be used at the same time to ...
... some cases, intensity ratios are very sensitive to both T e and ne . In this case, two or more diagnostics must be used at the same time to ...
Astronomy Astrophysics A VLT/FLAMES survey for massive binaries in Westerlund 1 &
... Context. There is growing evidence that a treatment of binarity amongst OB stars is essential for a full theory of stellar evolution. However the binary properties of massive stars – frequency, mass ratio & orbital separation – are still poorly constrained. Aims. In order to address this shortcoming ...
... Context. There is growing evidence that a treatment of binarity amongst OB stars is essential for a full theory of stellar evolution. However the binary properties of massive stars – frequency, mass ratio & orbital separation – are still poorly constrained. Aims. In order to address this shortcoming ...
OUTFLOW INFALL AND ROTATION IN HIGH
... • In Lstar ~ 104 LO (B stars) true disks found • In Lstar > 105 LO (O stars) no true disk (only toroids) found - but distance is large (few kpc) • Orion I (450 pc) does have disk, but luminosity ...
... • In Lstar ~ 104 LO (B stars) true disks found • In Lstar > 105 LO (O stars) no true disk (only toroids) found - but distance is large (few kpc) • Orion I (450 pc) does have disk, but luminosity ...
The fourth catalogue of Population I Wolf
... Finally, Azzopardi & Breysacher (1979, 1980), as a result of a new systematic search for W−R stars in the LMC with the ESO 40 cm GPO, using an interference filter centered at λ4650, were able to identify 17 new such objects in this galaxy. The LMC area covered by this survey (23 partially overlappin ...
... Finally, Azzopardi & Breysacher (1979, 1980), as a result of a new systematic search for W−R stars in the LMC with the ESO 40 cm GPO, using an interference filter centered at λ4650, were able to identify 17 new such objects in this galaxy. The LMC area covered by this survey (23 partially overlappin ...
Validation of Twelve Small Kepler Transiting Planets in the
... radius at which planets transition from being rocky to being dominated by thick hydrogen/helium envelopes, which presumably makes them unsuitable for life as we know it. The interface is currently thought to be between 1.5 and 2 R⊕ (e.g., Lopez & Fortney 2013; Weiss & Marcy 2014; Marcy et al. 2014; ...
... radius at which planets transition from being rocky to being dominated by thick hydrogen/helium envelopes, which presumably makes them unsuitable for life as we know it. The interface is currently thought to be between 1.5 and 2 R⊕ (e.g., Lopez & Fortney 2013; Weiss & Marcy 2014; Marcy et al. 2014; ...
Testing
... Infrared light reveals stars whose visible light is blocked by gas clouds. © 2010 Pearson Education, Inc. ...
... Infrared light reveals stars whose visible light is blocked by gas clouds. © 2010 Pearson Education, Inc. ...
VALIDATION OF TWELVE SMALL KEPLER TRANSITING PLANETS
... defined the local transit data as being within six transit durations either side of the mid-transit time, in order to provide an ample out-of-transit baseline. These local data were divided through by the final CoFiAM function and then stitched together to form our final light curve for analysis. 4. ...
... defined the local transit data as being within six transit durations either side of the mid-transit time, in order to provide an ample out-of-transit baseline. These local data were divided through by the final CoFiAM function and then stitched together to form our final light curve for analysis. 4. ...
rcw 49 at mid-infrared wavelengths: a glimpse from the
... radiation and as a consequence become bright in the neighborhood of a hot star if it is embedded in or surrounded by dust. Small dust grains can also be stochastically heated by absorption of UV radiation and reradiate at mid-IR wavelengths. IRAC [4.5] contains the bright hydrogen recombination line ...
... radiation and as a consequence become bright in the neighborhood of a hot star if it is embedded in or surrounded by dust. Small dust grains can also be stochastically heated by absorption of UV radiation and reradiate at mid-IR wavelengths. IRAC [4.5] contains the bright hydrogen recombination line ...
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.