New brown dwarfs and giant planets
... decreasing TiO, VO - dust depletion increasing FeH, CrH, water lower opacities increasingly strong alkali absorption Na, K, Cs, Rb, Li ...
... decreasing TiO, VO - dust depletion increasing FeH, CrH, water lower opacities increasingly strong alkali absorption Na, K, Cs, Rb, Li ...
ASTR-1020: Astronomy II Course Lecture Notes - Faculty
... Astronomy II at East Tennessee State University. ...
... Astronomy II at East Tennessee State University. ...
The Montreal White Dwarf Database: a Tool for the Community
... available data about the spectroscopically identified white dwarf that have been discovered to this day. Interactive tables and tools to easily make plots, histograms or display data have also been implemented (see below). The structure and philosophy behind MWDD was inspired in parts by other datab ...
... available data about the spectroscopically identified white dwarf that have been discovered to this day. Interactive tables and tools to easily make plots, histograms or display data have also been implemented (see below). The structure and philosophy behind MWDD was inspired in parts by other datab ...
What is it? - Carmenes - Calar Alto Observatory
... high temperatures that resemble those of the coolest stars and orbit very close to their suns (and their years last only a few days). With the improvement of the technology for the detection of exoplanets, especially through highly-stabilised spectroscopy for measuring the radial velocity reflex mot ...
... high temperatures that resemble those of the coolest stars and orbit very close to their suns (and their years last only a few days). With the improvement of the technology for the detection of exoplanets, especially through highly-stabilised spectroscopy for measuring the radial velocity reflex mot ...
Astronomy Final C - Tarleton State University
... 4. Genetic replication involves A.nucleic acids B.ATP C.amino acids D.genetic replication involves all of these 5. Degenerate gases ? cool without losing their pressure. A.can B.cannot 6. ? develop where supernova explosions leave behind a “core” of approximately 1.4 to 2 or 3 stellar masses. A.Brow ...
... 4. Genetic replication involves A.nucleic acids B.ATP C.amino acids D.genetic replication involves all of these 5. Degenerate gases ? cool without losing their pressure. A.can B.cannot 6. ? develop where supernova explosions leave behind a “core” of approximately 1.4 to 2 or 3 stellar masses. A.Brow ...
Abundance of Elements
... lifetime on main sequence is longer than the age of universe the chemical evolution of the universe ...
... lifetime on main sequence is longer than the age of universe the chemical evolution of the universe ...
takes its time doing so. The coolest white dwarfs
... hole. These stars (usually ranging from 1 to 8 solar masses) merely shrug off their outer layers leaving a core of mostly ionized carbon and oxygen. The average mass of a white dwarf is .6 solar masses, but they have been known to have a radius of about 1 earth radius. These stars are very dense. At ...
... hole. These stars (usually ranging from 1 to 8 solar masses) merely shrug off their outer layers leaving a core of mostly ionized carbon and oxygen. The average mass of a white dwarf is .6 solar masses, but they have been known to have a radius of about 1 earth radius. These stars are very dense. At ...
The Hertzsprung-Russell Diagram
... Giants and Supergiants are cool, but bright so they must be very large. ...
... Giants and Supergiants are cool, but bright so they must be very large. ...
white dwarf supernova
... When the white dwarf hits the mass limit, it gets hot enough for carbon fusion to start. It undergoes carbon fusion everywhere at once, so it’s a HUGE release of energy. This is called a “light curve” It plots luminosity as a function of time ...
... When the white dwarf hits the mass limit, it gets hot enough for carbon fusion to start. It undergoes carbon fusion everywhere at once, so it’s a HUGE release of energy. This is called a “light curve” It plots luminosity as a function of time ...
The H-R Diagram
... main sequence. Most white dwarfs have approximately the mass of the sun, but a radius about 0.01 to 0.001 of the radius of the sun (roughly about the size of a the earth). Their average density is about 106 to 108 solar density. They have exhausted all of their nuclear fuel, are no longer generating ...
... main sequence. Most white dwarfs have approximately the mass of the sun, but a radius about 0.01 to 0.001 of the radius of the sun (roughly about the size of a the earth). Their average density is about 106 to 108 solar density. They have exhausted all of their nuclear fuel, are no longer generating ...
M WHITE DWAR F The WhiTe-hoT Core
... When a star has used up all its hydrogen fuel, it expands rapidly. Eventually, it collapses under its own gravity and becomes a white dwarf. Although it’s out of fuel, a white dwarf still shines brightly, like an electric burner that glows after you turn off the stove. Like the electric burner, a wh ...
... When a star has used up all its hydrogen fuel, it expands rapidly. Eventually, it collapses under its own gravity and becomes a white dwarf. Although it’s out of fuel, a white dwarf still shines brightly, like an electric burner that glows after you turn off the stove. Like the electric burner, a wh ...
Stages 12 to 14
... The carbon rich core continues to contract and heat up. Carbon fusion requires a temperature of 500 to 600 million K. The core will contract until electron degeneracy pressure once again takes over, and contraction ends If the star is similar to the sun, the mass is too small, the ignition temperatu ...
... The carbon rich core continues to contract and heat up. Carbon fusion requires a temperature of 500 to 600 million K. The core will contract until electron degeneracy pressure once again takes over, and contraction ends If the star is similar to the sun, the mass is too small, the ignition temperatu ...
Poster 49 | PDF (852 kB)
... at a distance of 300 pc; from Burrows et al. (2001). (Fig 2., A. K. Mainzer, et al. 2003) Using the data acquired from our search we will be able to distinguish objects to 2MJ. ...
... at a distance of 300 pc; from Burrows et al. (2001). (Fig 2., A. K. Mainzer, et al. 2003) Using the data acquired from our search we will be able to distinguish objects to 2MJ. ...
At the Heart of the Matter: The Blue White Dwarf in M 57. Paul Temple
... DO He rich objects with temperatures in excess of 45,000K. The spectrum is dominated by the signature of HeII, although H and higher elements may be observed in smaller amounts. DB This class may be regarded as an extension of the DO group into lower temperature regions (below around 30,000K). The c ...
... DO He rich objects with temperatures in excess of 45,000K. The spectrum is dominated by the signature of HeII, although H and higher elements may be observed in smaller amounts. DB This class may be regarded as an extension of the DO group into lower temperature regions (below around 30,000K). The c ...
Brown Dwarfs and M Dwarfs
... Allard, Hauschildt, Tsuji, etc. • Major issues include: completeness of molecular opacities, convection (ML or 3D hydro), dust formation and opacity, initial conditions for young (t
... Allard, Hauschildt, Tsuji, etc. • Major issues include: completeness of molecular opacities, convection (ML or 3D hydro), dust formation and opacity, initial conditions for young (t
A Universe of Dwarfs and Giants
... own light. These objects are either very dim or even black when looked at in visible light. The little they radiate is mainly infra-red light. Brown dwarfs can be thought of as failed stars; much bigger than a planet but just not big enough to make it as a star. D type stars: These are also dwarf st ...
... own light. These objects are either very dim or even black when looked at in visible light. The little they radiate is mainly infra-red light. Brown dwarfs can be thought of as failed stars; much bigger than a planet but just not big enough to make it as a star. D type stars: These are also dwarf st ...
File - We All Love Science
... – Hot, compact stars. Mass of about our Sun but radius of our Earth (about 1% of the Sun) – Little surface area means they are dim, even though hot – Light not from burning fuel, as none is left – Light from residual heat as they cool – Temps range from 25,000K-4,000K ...
... – Hot, compact stars. Mass of about our Sun but radius of our Earth (about 1% of the Sun) – Little surface area means they are dim, even though hot – Light not from burning fuel, as none is left – Light from residual heat as they cool – Temps range from 25,000K-4,000K ...
White Dwarfs - Indiana University
... – All WDs have a common origin (PNN) with some hydrogen, upper limit of 10-4 solar masses to 10-15 solar masses of hydrogen (recall that 10-4 is the limit where H burning stops) – Only about 10-15 is needed to produce an optically thick H layer at the ...
... – All WDs have a common origin (PNN) with some hydrogen, upper limit of 10-4 solar masses to 10-15 solar masses of hydrogen (recall that 10-4 is the limit where H burning stops) – Only about 10-15 is needed to produce an optically thick H layer at the ...
Stellar Remnants
... – Adding mass to a white dwarf makes it shrink • the white dwarf will collapse when enough mass is added • maximum mass for collapse is called the Chandrasekhar Limit and has a value of 1.4 M • NO white dwarfs have masses above 1.4 solar masses ...
... – Adding mass to a white dwarf makes it shrink • the white dwarf will collapse when enough mass is added • maximum mass for collapse is called the Chandrasekhar Limit and has a value of 1.4 M • NO white dwarfs have masses above 1.4 solar masses ...
Student 1
... their cores and energy is generated at a slow rate through nuclear fusion of hydrogen into helium. These stars emit little light. In general, Red dwarfs less than 0.35 M☉ transport energy from the core to the surface by convection. Convection occurs because of opacity of the interior, which has a hi ...
... their cores and energy is generated at a slow rate through nuclear fusion of hydrogen into helium. These stars emit little light. In general, Red dwarfs less than 0.35 M☉ transport energy from the core to the surface by convection. Convection occurs because of opacity of the interior, which has a hi ...
Brown dwarf
Brown dwarfs are substellar objects not massive enough to sustain hydrogen-1 fusion reactions in their cores, unlike main-sequence stars. They occupy the mass range between the heaviest gas giants and the lightest stars, with an upper limit around 75 to 80 Jupiter masses (MJ). Brown dwarfs heavier than about 13 MJ are thought to fuse deuterium and those above ~65 MJ, fuse lithium as well. Brown dwarfs may be fully convective, with no layers or chemical differentiation by depth.The defining differences between a very-low-mass brown dwarf and a giant planet (~13 MJ) are debated. One school of thought is based on formation; the other, on the physics of the interior.Part of the debate concerns whether ""brown dwarfs"" must, by definition, have experienced fusion at some point in their history.Stars are categorized by spectral class, with brown dwarfs being designated as types M, L, T, and Y. Despite their name, brown dwarfs are of different colors. Many brown dwarfs would likely appear magenta to the human eye, or possibly orange/red. Brown dwarfs are not very luminous at visible wavelengths.Some planets are known to orbit brown dwarfs: 2M1207b, MOA-2007-BLG-192Lb, and 2MASS J044144bAt a distance of about 6.5 light years, the nearest known brown dwarf is Luhman 16, a binary system of brown dwarfs discovered in 2013. One brown dwarf, DENIS-P J082303.1-491201 b, from an ultracool binary system, has a mass of about 28 MJ, making it the largest known exoplanet (as of March 2014).