Star Formation in the Galactic Center
... “Standard” Star formation models are forbidden around SMBH due to huge tidal forces. BH would shear gas clouds with densities higher than the highest density cores of observed GMCs. Need nH > 1011 cm-3 R0.1-3. ...
... “Standard” Star formation models are forbidden around SMBH due to huge tidal forces. BH would shear gas clouds with densities higher than the highest density cores of observed GMCs. Need nH > 1011 cm-3 R0.1-3. ...
Recent advances in star
... areas of astronomy today. It is a key to understanding not only the evolution of the Milky Way, but also the immense luminosities of starburst and merging galaxies and the emission from high-redshift galaxies. Inevitably, most work on star formation focuses on the Milky Way, as here we have a grands ...
... areas of astronomy today. It is a key to understanding not only the evolution of the Milky Way, but also the immense luminosities of starburst and merging galaxies and the emission from high-redshift galaxies. Inevitably, most work on star formation focuses on the Milky Way, as here we have a grands ...
Imaging and spectroscopy of ejected common envelopes
... we are viewing this object in cross-section, and in some respects there is some resemblance between this nebula and the central parts of Abell 63. In fact, under suitable scaling the object takes on the appearance of a figure eight with the central star situated at the junction of the two halves of ...
... we are viewing this object in cross-section, and in some respects there is some resemblance between this nebula and the central parts of Abell 63. In fact, under suitable scaling the object takes on the appearance of a figure eight with the central star situated at the junction of the two halves of ...
Maximum Mass Limit of Stars on the Main Sequence
... complex answer. The maximum mass of a star is dependent on many factors including, stellar winds, metallicity, and the cloud from which it is formed. Another concern is the existence of a maximum mass cut-off. Theorists have proposed such a limit for over 50 years, and the values are dependent on th ...
... complex answer. The maximum mass of a star is dependent on many factors including, stellar winds, metallicity, and the cloud from which it is formed. Another concern is the existence of a maximum mass cut-off. Theorists have proposed such a limit for over 50 years, and the values are dependent on th ...
5 log5 − = − d . N
... Orbital measurements of the binary system can give M, and thus R from the mass-radius relationship. If the disc can be resolved, Rd can be determined, thus allowing us to calculate m& from measurements of LAcc. Novae: Accretion transfers H on to the white dwarf. This mass ‘piles up’ on the surface, ...
... Orbital measurements of the binary system can give M, and thus R from the mass-radius relationship. If the disc can be resolved, Rd can be determined, thus allowing us to calculate m& from measurements of LAcc. Novae: Accretion transfers H on to the white dwarf. This mass ‘piles up’ on the surface, ...
Earth and Beyond - Swinton Community School
... In nuclear fusion reactions, lighter nuclei are joined together (fused)…… ….to form heavier atomic nuclei. This releases massive amounts or energy. In our Sun, a typical star, hydrogen is being fused into helium, this provides the energy for life on Earth. ...
... In nuclear fusion reactions, lighter nuclei are joined together (fused)…… ….to form heavier atomic nuclei. This releases massive amounts or energy. In our Sun, a typical star, hydrogen is being fused into helium, this provides the energy for life on Earth. ...
UV habitable zones around M stars - IAFE
... To date (June 2007) nine dM stars were found hosting planetary systems. Three of them were observed by IUE: HIP 74995 (M3V), HIP 109388 (M3.5V) and HIP 113020 (M4V). In Table 1 we list some physical parameters of the host stars and their corresponding planets. The flare stars AD Leo (M3.5Ve) and EV ...
... To date (June 2007) nine dM stars were found hosting planetary systems. Three of them were observed by IUE: HIP 74995 (M3V), HIP 109388 (M3.5V) and HIP 113020 (M4V). In Table 1 we list some physical parameters of the host stars and their corresponding planets. The flare stars AD Leo (M3.5Ve) and EV ...
Star Formation Triggers More Star Formation
... Fusion reactions begin as soon as the center of the protostar gets hot enough (~1 million K) Hydrogen to Helium fusion starts out slowly Heat doesn’t provide enough outward pressure to stop collapse. As core temperature goes up, fusion reactions happen ...
... Fusion reactions begin as soon as the center of the protostar gets hot enough (~1 million K) Hydrogen to Helium fusion starts out slowly Heat doesn’t provide enough outward pressure to stop collapse. As core temperature goes up, fusion reactions happen ...
protostars and pre-main
... using guessed central values for P, T, iterate until match with outer boundary conditions. ...
... using guessed central values for P, T, iterate until match with outer boundary conditions. ...
DETECTION OF PLANETARY TRANSITS ACROSS A SUN
... of A, the effective temperature of the planet is Tp ≈ 1400(1 ! A)1/4 K. This implies a thermal velocity for hydrogen of vt ! 6.0 km s!1. This is roughly a factor of 7 less than the calculated escape velocity of ve ≈ 42 km s!1, confirming that these planets should not be losing significant amounts of ...
... of A, the effective temperature of the planet is Tp ≈ 1400(1 ! A)1/4 K. This implies a thermal velocity for hydrogen of vt ! 6.0 km s!1. This is roughly a factor of 7 less than the calculated escape velocity of ve ≈ 42 km s!1, confirming that these planets should not be losing significant amounts of ...
L45 DETECTION OF PLANETARY TRANSITS ACROSS A SUN
... of A, the effective temperature of the planet is Tp ≈ 1400(1 2 A)1/4 K. This implies a thermal velocity for hydrogen of vt & 6.0 km s21. This is roughly a factor of 7 less than the calculated escape velocity of ve ≈ 42 km s21, confirming that these planets should not be losing significant amounts of ...
... of A, the effective temperature of the planet is Tp ≈ 1400(1 2 A)1/4 K. This implies a thermal velocity for hydrogen of vt & 6.0 km s21. This is roughly a factor of 7 less than the calculated escape velocity of ve ≈ 42 km s21, confirming that these planets should not be losing significant amounts of ...
Heading for the Pole - MNASSA Page
... but definitely not without some effort. This unknown, yet well-known, point in the starry sky is only 10′ north of the relatively bright 8.7 magnitude HD 98784, which is the middle star of a short star-string. (Because the pole is rotating relatively fast, directions count for early evenings towards ...
... but definitely not without some effort. This unknown, yet well-known, point in the starry sky is only 10′ north of the relatively bright 8.7 magnitude HD 98784, which is the middle star of a short star-string. (Because the pole is rotating relatively fast, directions count for early evenings towards ...
astrophysics - Uplift Summit Intl
... (c) Explain, by reference to the Chandrasekhar limit, why the final stage of the evolutionary path of the Sun is at F. White dwarfs are found in region F of the HR diagram. Main sequence stars that end up with a mass under the Chandrasekhar limit of 1.4 solar masses will become white dwarfs. (d) On ...
... (c) Explain, by reference to the Chandrasekhar limit, why the final stage of the evolutionary path of the Sun is at F. White dwarfs are found in region F of the HR diagram. Main sequence stars that end up with a mass under the Chandrasekhar limit of 1.4 solar masses will become white dwarfs. (d) On ...
David S. Stevenson
... focused on the overall size of the planet and its location within the stellar habitable zone. However, many additional factors exist that affect their potential ability to harbor life. This is particularly true of planets orbiting red dwarf stars, for it is these worlds that will have the most time ...
... focused on the overall size of the planet and its location within the stellar habitable zone. However, many additional factors exist that affect their potential ability to harbor life. This is particularly true of planets orbiting red dwarf stars, for it is these worlds that will have the most time ...
Hvězdný make up Proč jsou hvězdy skvrnité?
... spots - for decades or centuries. As the star rotates, periodic variations in the brightness, spectrum, and magnetic field are observed. ...
... spots - for decades or centuries. As the star rotates, periodic variations in the brightness, spectrum, and magnetic field are observed. ...
Document
... Earth has Newtonian Physics; BHs have Relativistic Physics if you ride into a BH you go in if you watch someone ride in they stay at Rs ...
... Earth has Newtonian Physics; BHs have Relativistic Physics if you ride into a BH you go in if you watch someone ride in they stay at Rs ...
AS 701 - INTRODUCTION TO ASTROPHYSICS COURSE OVERVIEW - FALL 2013
... and gravitational physics, properties of stars, stellar structure, stellar evolution, dynamics of binary stars systems and star clusters, types of galaxies, galactic structure and dynamics, active galaxies and some cosmological topics. COURSE STRUCTURE AND PHILOSOPHY: The course is intended to provi ...
... and gravitational physics, properties of stars, stellar structure, stellar evolution, dynamics of binary stars systems and star clusters, types of galaxies, galactic structure and dynamics, active galaxies and some cosmological topics. COURSE STRUCTURE AND PHILOSOPHY: The course is intended to provi ...
KS4 Earth and Beyond 2637KB
... object and contains about 98% of the total mass in the Solar System. The Sun is a massive ball of hot, glowing gas and is mostly made of hydrogen and helium. It is more than 4.5 billion years old! Scientists once thought that the Sun was powered by chemical reactions but this couldn’t explain how it ...
... object and contains about 98% of the total mass in the Solar System. The Sun is a massive ball of hot, glowing gas and is mostly made of hydrogen and helium. It is more than 4.5 billion years old! Scientists once thought that the Sun was powered by chemical reactions but this couldn’t explain how it ...
Earth and Beyond - Prairie Rose School Division No. 8
... object and contains about 98% of the total mass in the Solar System. The Sun is a massive ball of hot, glowing gas and is mostly made of hydrogen and helium. It is more than 4.5 billion years old! Scientists once thought that the Sun was powered by chemical reactions but this couldn’t explain how it ...
... object and contains about 98% of the total mass in the Solar System. The Sun is a massive ball of hot, glowing gas and is mostly made of hydrogen and helium. It is more than 4.5 billion years old! Scientists once thought that the Sun was powered by chemical reactions but this couldn’t explain how it ...
Hertzsprung-Russell Diagram, Flux, Luminosity, Magnitude—10 Oct Outline •
... of classifying spectra. Hertzsprung‐Russell diagram ...
... of classifying spectra. Hertzsprung‐Russell diagram ...
Astrophysics for the next decade
... How did stars and planets form? • Star formation shrouded in dust – Transition from absorbing cloud to self-luminous object ...
... How did stars and planets form? • Star formation shrouded in dust – Transition from absorbing cloud to self-luminous object ...
death_high_mass_2b
... The light-house effect • The pulsar is similar to a light house. As the beam of light passes by us we get a very large signal. When the beam moves away the signal dies out. • Some pulsars give a burst of light every second. This means the neutron star is ...
... The light-house effect • The pulsar is similar to a light house. As the beam of light passes by us we get a very large signal. When the beam moves away the signal dies out. • Some pulsars give a burst of light every second. This means the neutron star is ...
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.