Post-Main Sequence Evolution – Low and Intermediate Mass Stars
... little helium burns before expansion puts out the runaway after only a few minutes (a factor of a few times the sound crossing time for the helium core). This large luminosity does not arrive at the surface but instead goes into expanding both the helium core and the envelope outside it. The hydroge ...
... little helium burns before expansion puts out the runaway after only a few minutes (a factor of a few times the sound crossing time for the helium core). This large luminosity does not arrive at the surface but instead goes into expanding both the helium core and the envelope outside it. The hydroge ...
Enhanced lithium depletion in Sun-like stars with orbiting planets.
... planets and the rest, which we will designate as a comparison sample, (we often call them “single” stars) have no detected planets so far. If there are planets around these “single” stars, their masses and orbital parameters will be different from those already known. We use this comparison sample t ...
... planets and the rest, which we will designate as a comparison sample, (we often call them “single” stars) have no detected planets so far. If there are planets around these “single” stars, their masses and orbital parameters will be different from those already known. We use this comparison sample t ...
The colours of the Universe, the amateur astronomical spectroscopy.
... Mintaka's spectrum is located mainly in the ultraviolet. It is a hot star, according to Planck's law we can estimate its temperature at about 25 000 K. Its lightness class is II, white coloured, bright giants. On the graph of this there star are presented some absorption lines of chemical elements s ...
... Mintaka's spectrum is located mainly in the ultraviolet. It is a hot star, according to Planck's law we can estimate its temperature at about 25 000 K. Its lightness class is II, white coloured, bright giants. On the graph of this there star are presented some absorption lines of chemical elements s ...
Read the information on Hertzsprung
... radiates in one second, but you can think of it as how bright or how dim the star appears. The luminosity scale is a "ratio scale" in which stars are compared to each other based upon a reference (our sun). The horizontal axis represents the star’s surface temperature (not the star’s core temperatur ...
... radiates in one second, but you can think of it as how bright or how dim the star appears. The luminosity scale is a "ratio scale" in which stars are compared to each other based upon a reference (our sun). The horizontal axis represents the star’s surface temperature (not the star’s core temperatur ...
Galaxies (and stars) in the far infrared: results from the AKARI All
... powerful tool to understand the properties of all classes of objects in the Universe. But first, we need to know: what they are? From our point of view, the crucial point was: which of these sources are the galaxies, how they can be distinguished from sources which belong ...
... powerful tool to understand the properties of all classes of objects in the Universe. But first, we need to know: what they are? From our point of view, the crucial point was: which of these sources are the galaxies, how they can be distinguished from sources which belong ...
Test 3 Review
... Mass of nuc. 3 is slightly less than mass of (nuc. 1 + nuc. 2). The lost mass is converted to energy. Why? Einstein's conservation of mass and energy, E = mc2. Sum of mass and energy always conserved in reactions. Fusion reactions power stars. Chain of nuclear reactions called "proton-proton chain" ...
... Mass of nuc. 3 is slightly less than mass of (nuc. 1 + nuc. 2). The lost mass is converted to energy. Why? Einstein's conservation of mass and energy, E = mc2. Sum of mass and energy always conserved in reactions. Fusion reactions power stars. Chain of nuclear reactions called "proton-proton chain" ...
REGIONAL exam 2013
... 32. In the Type II supernova spectrum shown above, which spectral feature shows a P Cygni profile? A. B. C. D. E. F. G. ...
... 32. In the Type II supernova spectrum shown above, which spectral feature shows a P Cygni profile? A. B. C. D. E. F. G. ...
nebula - Harding University
... of Orion – Monoceros Region The following image is a radar map of the Orion – Monoceros region of the sky taken at a wavelength of 2.6 mm. The 2.6 mm wavelength radar image maps CO concentrations. The concentrations of hydrogen are typically four orders of magnitude greater than CO in interstellar ...
... of Orion – Monoceros Region The following image is a radar map of the Orion – Monoceros region of the sky taken at a wavelength of 2.6 mm. The 2.6 mm wavelength radar image maps CO concentrations. The concentrations of hydrogen are typically four orders of magnitude greater than CO in interstellar ...
Lecture19
... White Dwarfs White dwarfs are supported by electron degeneracy pressure, which is why they don’t contract and burn their core material. They have no fusion going on; they cool and fade away. Usually made of carbon, but sometimes helium (very low mass stars can’t even burn helium). ...
... White Dwarfs White dwarfs are supported by electron degeneracy pressure, which is why they don’t contract and burn their core material. They have no fusion going on; they cool and fade away. Usually made of carbon, but sometimes helium (very low mass stars can’t even burn helium). ...
The Lives of Stars
... “evaporate,” from such a cluster • A stellar association is a group of newborn stars that are moving apart so rapidly that their gravitational attraction for one another cannot pull them into orbit about one another ...
... “evaporate,” from such a cluster • A stellar association is a group of newborn stars that are moving apart so rapidly that their gravitational attraction for one another cannot pull them into orbit about one another ...
Your Star: _____________________ Write down the wavelength at which the one
... If distance is in parsecs and parallax is in arcsec ...
... If distance is in parsecs and parallax is in arcsec ...
Helium Fusion What Will Happen When There Is No More Helium in
... • Early stages after main sequence – Similar to a low mass star, but happen much faster • No helium flash ...
... • Early stages after main sequence – Similar to a low mass star, but happen much faster • No helium flash ...
– 1 – 1. Historical Notes for Ay 123 1.1.
... Annie Jump Cannon – worked with Pickering at Harvard College Observatory, did most of the classifications for the Henry Draper Catalog, her job title was “computer”. Henrietta Leavitt – worked as an assistant to Baade at the Mount Wilson Observatory. In 1912 she discovered the period – luminosity la ...
... Annie Jump Cannon – worked with Pickering at Harvard College Observatory, did most of the classifications for the Henry Draper Catalog, her job title was “computer”. Henrietta Leavitt – worked as an assistant to Baade at the Mount Wilson Observatory. In 1912 she discovered the period – luminosity la ...
Stars - gilbertmath.com
... which in turn causes tightly packed ___________ to heat up. As the ____________________ climbs, the core begins to glow. This is called a __________________, a star in its __________ stage of formation. ...
... which in turn causes tightly packed ___________ to heat up. As the ____________________ climbs, the core begins to glow. This is called a __________________, a star in its __________ stage of formation. ...
The Milky Way
... So Can Stochastic Star Formation • Random birth of Massive Stars • Their SN explosions compress nearby clouds & make new stars • Differential rotation of galaxy yields spiral appearance by streching the stars out • This best explains "rattier", broken-up spirals (like the Milky Way, though some Den ...
... So Can Stochastic Star Formation • Random birth of Massive Stars • Their SN explosions compress nearby clouds & make new stars • Differential rotation of galaxy yields spiral appearance by streching the stars out • This best explains "rattier", broken-up spirals (like the Milky Way, though some Den ...
Supernovae Gamma-Ray Bursts and and some of their uses
... Occur in star-forming galaxies only Type I’s are further divided into subclasses (Ia, Ib, Ic) again based on their spectral properties. There are also “peculiar” cases. Type Ia SNe are believed to result from explosions of Chandrasekar mass white dwarfs. All other types are thought to result from th ...
... Occur in star-forming galaxies only Type I’s are further divided into subclasses (Ia, Ib, Ic) again based on their spectral properties. There are also “peculiar” cases. Type Ia SNe are believed to result from explosions of Chandrasekar mass white dwarfs. All other types are thought to result from th ...
– 1 – 1. Cosmochronology
... panoply of stellar evolution models, tracks, and isochrones. While ages can be derived for clusters, they are thus quite uncertain due to systematic modeling uncertainties, not to random observational errors. Another feature of stellar evolution which is somewhat more promising is the population of ...
... panoply of stellar evolution models, tracks, and isochrones. While ages can be derived for clusters, they are thus quite uncertain due to systematic modeling uncertainties, not to random observational errors. Another feature of stellar evolution which is somewhat more promising is the population of ...
Constituents of the Milky Way
... For individual stars that aren’t in clusters (like the Sun), we can’t use the cluster turnoff method to measure an age. For instance, a lone G star might be young, or it might be 10 billion years old. How do we measure its age? The universe contained only hydrogen, helium, and one other element (lit ...
... For individual stars that aren’t in clusters (like the Sun), we can’t use the cluster turnoff method to measure an age. For instance, a lone G star might be young, or it might be 10 billion years old. How do we measure its age? The universe contained only hydrogen, helium, and one other element (lit ...
SRP_Space_Lesson 5 - Scientist in Residence Program
... is to say, the stars do not really form that shape. The first observers of the sky thought that the stars in a constellation when connected resembled a shape that was familiar to them, and so they named it. This allowed them to map the movement of the stars throughout the seasons, which helped the d ...
... is to say, the stars do not really form that shape. The first observers of the sky thought that the stars in a constellation when connected resembled a shape that was familiar to them, and so they named it. This allowed them to map the movement of the stars throughout the seasons, which helped the d ...
Document
... E. Death of a Star - 4 Solar Masses or more (cont). -After Supernova explosion, stellar remnant is dependant upon how much of core is left. -1. Neutron “Star”-- Core remnant is between 1.4 and 3.0 solar masses - Compression will be so great that protons and electrons of matter in core will combine t ...
... E. Death of a Star - 4 Solar Masses or more (cont). -After Supernova explosion, stellar remnant is dependant upon how much of core is left. -1. Neutron “Star”-- Core remnant is between 1.4 and 3.0 solar masses - Compression will be so great that protons and electrons of matter in core will combine t ...
3-color photometry of stellar cluster - Kiepenheuer
... One way to organise stars is to plot the luminosity against their spectral type or effective temperature. This kind of diagrams are the so called Hertzsprung-Russell diagrams (HRD). If many stars are plotted it is immediately clear that stars appear in specific ranges of these diagrams. In the cente ...
... One way to organise stars is to plot the luminosity against their spectral type or effective temperature. This kind of diagrams are the so called Hertzsprung-Russell diagrams (HRD). If many stars are plotted it is immediately clear that stars appear in specific ranges of these diagrams. In the cente ...
Stellar Magnetic Activity
... Red dwarfs and BY Dra phenomenon Red dwarfs are main-sequence stars with the mass range from 0.08Mo . to 0.5 Mo .. The lower mass limit is the critical mass for hydrogen burning in the central cores of stars with solar abundances, while the upper limit corresponds to the spectral class M0. The radi ...
... Red dwarfs and BY Dra phenomenon Red dwarfs are main-sequence stars with the mass range from 0.08Mo . to 0.5 Mo .. The lower mass limit is the critical mass for hydrogen burning in the central cores of stars with solar abundances, while the upper limit corresponds to the spectral class M0. The radi ...
Spectral Variations of Three RV Tauri Stars Donald K. Walter
... conclusions other than to say that TT Oph moves around the HR diagram during its pulsation cycle. It may close the loop during the first part of the cycle (0 to 0.42) where there is currently a gap in the data. Future analysis of additional spectra should resolve ...
... conclusions other than to say that TT Oph moves around the HR diagram during its pulsation cycle. It may close the loop during the first part of the cycle (0 to 0.42) where there is currently a gap in the data. Future analysis of additional spectra should resolve ...
AST1100 Lecture Notes
... We have so far seen temperature on the x-axis. The temperature of a star is directly related to its color and one can therefore also use the B − V color index (see the lecture on cosmic distances) on the x-axis. There is also another another possibility: spectral classes. Stars are classified accord ...
... We have so far seen temperature on the x-axis. The temperature of a star is directly related to its color and one can therefore also use the B − V color index (see the lecture on cosmic distances) on the x-axis. There is also another another possibility: spectral classes. Stars are classified accord ...
PC3692: Physics of Stellar Structure (and Evolution)
... Note that the colour index is independent of the source distance. Very hot stars are blue, which may have B − V = −0.3, while cooler stars are red and may have B − V = 2. Example 1.4 For the Sun, the B − V colour index is B − V = MB − MV = 5.48 − 4.83 = 0.65 Stars can be divided into various classes ...
... Note that the colour index is independent of the source distance. Very hot stars are blue, which may have B − V = −0.3, while cooler stars are red and may have B − V = 2. Example 1.4 For the Sun, the B − V colour index is B − V = MB − MV = 5.48 − 4.83 = 0.65 Stars can be divided into various classes ...
Stellar classification
In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Light from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the rainbow of colors interspersed with absorption lines. Each line indicates an ion of a certain chemical element, with the line strength indicating the abundance of that ion. The relative abundance of the different ions varies with the temperature of the photosphere. The spectral class of a star is a short code summarizing the ionization state, giving an objective measure of the photosphere's temperature and density.Most stars are currently classified under the Morgan–Keenan (MK) system using the letters O, B, A, F, G, K, and M, a sequence from the hottest (O type) to the coolest (M type). Each letter class is then subdivided using a numeric digit with 0 being hottest and 9 being coolest (e.g. A8, A9, F0, F1 form a sequence from hotter to cooler). The sequence has been expanded with classes for other stars and star-like objects that do not fit in the classical system, such class D for white dwarfs and class C for carbon stars.In the MK system a luminosity class is added to the spectral class using Roman numerals. This is based on the width of certain absorption lines in the star's spectrum which vary with the density of the atmosphere and so distinguish giant stars from dwarfs. Luminosity class 0 or Ia+ stars for hypergiants, class I stars for supergiants, class II for bright giants, class III for regular giants, class IV for sub-giants, class V for main-sequence stars, class sd for sub-dwarfs, and class D for white dwarfs. The full spectral class for the Sun is then G2V, indicating a main-sequence star with a temperature around 5,800K.