Unravelling the Origin and Evolution of Our Galaxy
... than our Sun. These are all within a distance of about 100 light-years. The planets detectable by this method are rather massive, comparable to Jupiter (which has about 300 times the mass of Earth). The systems have some surprising properties: two thirds of these giant planets are orbiting their hos ...
... than our Sun. These are all within a distance of about 100 light-years. The planets detectable by this method are rather massive, comparable to Jupiter (which has about 300 times the mass of Earth). The systems have some surprising properties: two thirds of these giant planets are orbiting their hos ...
Linking Gas Fractions to Bimodalities in Galaxy Properties
... mHI from mu is not correlation strength but scatter. Most of the 0.92 mag scatter in the mu –mHI relation is not explained by the errors. This scatter likely represents variations in u-band extinction, molecular-to-atomic gas ratios, and the physical conditions required to convert a gas reservoir in ...
... mHI from mu is not correlation strength but scatter. Most of the 0.92 mag scatter in the mu –mHI relation is not explained by the errors. This scatter likely represents variations in u-band extinction, molecular-to-atomic gas ratios, and the physical conditions required to convert a gas reservoir in ...
Velocity dispersion around ellipticals in MOND
... the velocity-dispersion profiles were found to decline with radius, up to 5 effective radii, thereby requiring no dark matter at all. Dekel et al. (2005) show that the data are still compatible with the usual dark matter models, if the planetary nebulae tracers have particularly radial orbits in the ...
... the velocity-dispersion profiles were found to decline with radius, up to 5 effective radii, thereby requiring no dark matter at all. Dekel et al. (2005) show that the data are still compatible with the usual dark matter models, if the planetary nebulae tracers have particularly radial orbits in the ...
Teacher`s Guide - Cornell Science Inquiry Partnerships
... This activity makes an analogy between stars and humans, which are easier to relate to. By having students graph properties of populations of humans based on a “snapshot” in time (i.e., a photograph or a census) and seeing what they can infer about these populations and how they change, the activity ...
... This activity makes an analogy between stars and humans, which are easier to relate to. By having students graph properties of populations of humans based on a “snapshot” in time (i.e., a photograph or a census) and seeing what they can infer about these populations and how they change, the activity ...
white paper
... frequency, along with other existing and planned facilities. The ngVLA fills the gap around 1cm, providing a resolution of better than 10mas at 1cm. As we shall see below, coupled with the high sensitivity of the array, this resolution provides a unique window into the formation of planets on scales ...
... frequency, along with other existing and planned facilities. The ngVLA fills the gap around 1cm, providing a resolution of better than 10mas at 1cm. As we shall see below, coupled with the high sensitivity of the array, this resolution provides a unique window into the formation of planets on scales ...
Public outreach: any limit?
... 66 candidates selected so far (follow-up spectroscopy in course) ...
... 66 candidates selected so far (follow-up spectroscopy in course) ...
$doc.title
... obje t brighter than about 1/3 L , whi h orresponds to a period of about 5 minutes for a 1.4 M neutron star mass donor. Additionally, ultra ompa t binaries should stand out as being too hot for their magnitudes when plotted in a olor magnitude diagram. We note that ar hival HST data an be used ...
... obje t brighter than about 1/3 L , whi h orresponds to a period of about 5 minutes for a 1.4 M neutron star mass donor. Additionally, ultra ompa t binaries should stand out as being too hot for their magnitudes when plotted in a olor magnitude diagram. We note that ar hival HST data an be used ...
ATLAS lifts the Cup: discovery of a new Milky Way satellite in Crater⋆†
... No globular cluster has ever accomplished the feat of prolonging its star formation by several Gyr. Therefore, if our hypothesis that the blue bright stars in Crater are blue loop giants is correct, the new satellite should be classified as a dwarf galaxy with unusual properties. Note that only 10◦ ...
... No globular cluster has ever accomplished the feat of prolonging its star formation by several Gyr. Therefore, if our hypothesis that the blue bright stars in Crater are blue loop giants is correct, the new satellite should be classified as a dwarf galaxy with unusual properties. Note that only 10◦ ...
Dynamical Properties of Infrared Dark Clouds
... Infrared Dark Clouds (IRDCs) are a new class of interstellar clouds seen as dark extinction features against the bright Galactic background at mid-infrared (mid-IR) wavelengths. Studies thus far have shown these IRDCs to be dense (>105 cm-3), cold (<25 K), and to have very high column densities (>10 ...
... Infrared Dark Clouds (IRDCs) are a new class of interstellar clouds seen as dark extinction features against the bright Galactic background at mid-infrared (mid-IR) wavelengths. Studies thus far have shown these IRDCs to be dense (>105 cm-3), cold (<25 K), and to have very high column densities (>10 ...
“White Hot” Star Lab
... tape or placing a ruler next to an object to find out how long it is. Direct measurements are made on objects that can be easily handled. If objects are too big or too far away, such as the case with planets and stars, indirect measurements must be made. Parallax is an example of an indirect measure ...
... tape or placing a ruler next to an object to find out how long it is. Direct measurements are made on objects that can be easily handled. If objects are too big or too far away, such as the case with planets and stars, indirect measurements must be made. Parallax is an example of an indirect measure ...
ALFALFA H-alpha: The Star-Formation-Rate Density
... For astronomers studying past star-formation rates (SFRs), distances play the role of a time machine. Light travels at a finite speed; it travels slowly enough that astronomers can still view light from the Big Bang. Light emitted by the Sun takes more than eight minutes to reach Earth, roughly five ...
... For astronomers studying past star-formation rates (SFRs), distances play the role of a time machine. Light travels at a finite speed; it travels slowly enough that astronomers can still view light from the Big Bang. Light emitted by the Sun takes more than eight minutes to reach Earth, roughly five ...
GUM31 Y ALREDEDORES
... bubble. Since the dynamical age is larger than the duration of the WR phase of the star, the progenitor of the current WR star has also contributed in shaping the nebula. The nebula is in the momentum conserving stage or in an intermediate stage between energy and momentum conservation. ...
... bubble. Since the dynamical age is larger than the duration of the WR phase of the star, the progenitor of the current WR star has also contributed in shaping the nebula. The nebula is in the momentum conserving stage or in an intermediate stage between energy and momentum conservation. ...
Written by G. Jeffrey Taylor
... predicted for formation in material flowing from asymptotic giant branch starts, nicknamed AGB stars. Stars with masses not too much different from the Sun reach this stage after using up all their hydrogen via nuclear fusion. Astrophysicists calculate that the nuclear environment in AGB stars would ...
... predicted for formation in material flowing from asymptotic giant branch starts, nicknamed AGB stars. Stars with masses not too much different from the Sun reach this stage after using up all their hydrogen via nuclear fusion. Astrophysicists calculate that the nuclear environment in AGB stars would ...
Are WE CORRECTLY Measuring the Star formation in galaxies?
... Input the CMD-SFRs into different models to predict the UV fluxes Compare the UV fluxes to the observations ...
... Input the CMD-SFRs into different models to predict the UV fluxes Compare the UV fluxes to the observations ...
The LMC transition star R84 and the core of the LH 39 OB association
... data. If the PSF used for the deconvolution is derived from stars as bright as the object to deconvolve, Magain et al. (1997) have shown that the photometry of the point sources is basically photon noise limited even in the case of rather strong blends (e.g. two stars as close as one fwhm). However, ...
... data. If the PSF used for the deconvolution is derived from stars as bright as the object to deconvolve, Magain et al. (1997) have shown that the photometry of the point sources is basically photon noise limited even in the case of rather strong blends (e.g. two stars as close as one fwhm). However, ...
CEA - Nuclear astrophysics
... stronomy deals with the position and observation of the objects in our Universe, from planets to galaxies. It is the oldest of the sciences. Astrophysics is the study of the physical properties of these objects. It dates from the start of the 20th century. Nuclear astrophysics is the marriage of nuc ...
... stronomy deals with the position and observation of the objects in our Universe, from planets to galaxies. It is the oldest of the sciences. Astrophysics is the study of the physical properties of these objects. It dates from the start of the 20th century. Nuclear astrophysics is the marriage of nuc ...
Document
... astronomers can carry out look-back studies to assess empirically when and how galaxies formed. The distant universe became a prominent field of astronomical research during the final decade of the twentieth century. At that time the Lyman break technique in combination with the new generation of 8- ...
... astronomers can carry out look-back studies to assess empirically when and how galaxies formed. The distant universe became a prominent field of astronomical research during the final decade of the twentieth century. At that time the Lyman break technique in combination with the new generation of 8- ...
Star-Galaxy Classification in Multi
... entire sample of sources can inform the prior probabilities for each individual source. Consider the scenario where a G model fits data F i only slightly better than the best S model, while all other G models give poor fits and all other S models give nearly as likely fits. In this case, ignoring al ...
... entire sample of sources can inform the prior probabilities for each individual source. Consider the scenario where a G model fits data F i only slightly better than the best S model, while all other G models give poor fits and all other S models give nearly as likely fits. In this case, ignoring al ...
Word
... Light and all electromagnetic waves travel at a speed of nearly 300 000 km s , which is found to be the same by all observers, no matter how they are moving relative to one another. Ultimately this is because the speed of light is the constant conversion factor between measures of space and time, th ...
... Light and all electromagnetic waves travel at a speed of nearly 300 000 km s , which is found to be the same by all observers, no matter how they are moving relative to one another. Ultimately this is because the speed of light is the constant conversion factor between measures of space and time, th ...
The quest for cradles of life: using the fundamental metallicity
... Sloan Digital Sky Survey (SDSS) show that the three key physical properties (total stellar mass, ongoing star formation rate and gas-phase metallicity) are intricately linked with minimal scatter for more than a 140,000 galaxies in the local Universe through an intrinsic “Fundamental Metallicity Rel ...
... Sloan Digital Sky Survey (SDSS) show that the three key physical properties (total stellar mass, ongoing star formation rate and gas-phase metallicity) are intricately linked with minimal scatter for more than a 140,000 galaxies in the local Universe through an intrinsic “Fundamental Metallicity Rel ...
supernova remnants: a link between massive stars and the
... Namely, free expansion, which lasts less than 200300 years, adiabatic, about 20,000 years in duration, and radiative, up to ∼500,000 to ∼700,000 years. The SNR disappears when the expansion velocity of the swept-up matter becomes comparable to the random motions of the interstellar clouds and it mer ...
... Namely, free expansion, which lasts less than 200300 years, adiabatic, about 20,000 years in duration, and radiative, up to ∼500,000 to ∼700,000 years. The SNR disappears when the expansion velocity of the swept-up matter becomes comparable to the random motions of the interstellar clouds and it mer ...
Gas and dust evolution in distant AGN
... Chemical version of the cosmic downsizing (anti-hierarchical growth) Evolution of the Mass-Metallicity relation: massive galaxies chemically evolve rapidly at high-z QSOs ...
... Chemical version of the cosmic downsizing (anti-hierarchical growth) Evolution of the Mass-Metallicity relation: massive galaxies chemically evolve rapidly at high-z QSOs ...
Observations of Near Infrared Extragalactic Background (NIR_EBL)
... a 100 s observation, including both instrument noise and sample variance. We assume there are no Pop III fluctuations detectable at I-band, following the IRB star spectrum in Fig. 3. NAME can easily detect the optimistic Pop III signal (this model produces a cumulative background of 25 nW m-2 sr-1, ...
... a 100 s observation, including both instrument noise and sample variance. We assume there are no Pop III fluctuations detectable at I-band, following the IRB star spectrum in Fig. 3. NAME can easily detect the optimistic Pop III signal (this model produces a cumulative background of 25 nW m-2 sr-1, ...
Ch. 22
... Astronomers now believe that most of any galaxy’s mass lies beyond the portions of the galaxy that we can see. a. Yes, because the orbital velocity of gas and stars remains fairly constant as we look farther from the galactic center, even beyond where most stars are found. b. Yes, because dark matt ...
... Astronomers now believe that most of any galaxy’s mass lies beyond the portions of the galaxy that we can see. a. Yes, because the orbital velocity of gas and stars remains fairly constant as we look farther from the galactic center, even beyond where most stars are found. b. Yes, because dark matt ...
Star counts in the Galaxy-Simulating from very deep to very shallow
... The code attempts to improve upon several technical aspects of star count models, by: dealing with very complete input libraries of evolutionary tracks; using a stellar spectral library to simulate the photometry in virtually any broad-band system; being very versatile allowing easy changes in the i ...
... The code attempts to improve upon several technical aspects of star count models, by: dealing with very complete input libraries of evolutionary tracks; using a stellar spectral library to simulate the photometry in virtually any broad-band system; being very versatile allowing easy changes in the i ...
Cosmic distance ladder
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A real direct distance measurement of an astronomical object is possible only for those objects that are ""close enough"" (within about a thousand parsecs) to Earth. The techniques for determining distances to more distant objects are all based on various measured correlations between methods that work at close distances and methods that work at larger distances. Several methods rely on a standard candle, which is an astronomical object that has a known luminosity.The ladder analogy arises because no one technique can measure distances at all ranges encountered in astronomy. Instead, one method can be used to measure nearby distances, a second can be used to measure nearby to intermediate distances, and so on. Each rung of the ladder provides information that can be used to determine the distances at the next higher rung.