Stellar Metamorphosis as Alternative to Nebular Hypothesis
... 2. The system TYC 8241 2652 had an alleged proto-planetary disk. This disk glowed brightly in the infrared when discovered in 1983, but as of 2 ½ years ago has stopped glowing in the infrared.[3] This system falsifies the idea that disks create Earth sized objects because the proto-planetary disk m ...
... 2. The system TYC 8241 2652 had an alleged proto-planetary disk. This disk glowed brightly in the infrared when discovered in 1983, but as of 2 ½ years ago has stopped glowing in the infrared.[3] This system falsifies the idea that disks create Earth sized objects because the proto-planetary disk m ...
The first carbon-enhanced metal-poor star found in the Sculptor
... carried out in the central field of Sculptor. Abundances have been measured for Fe, Mg, Ca, Si, and Ti with intermediate-resolution (IR) spectroscopy (Kirby et al. 2009) and high-resolution (HR) spectroscopy for ∼100 stars (Dwarf Abundances & Radialvelocities Team (DART) survey, Tolstoy et al. 2009; ...
... carried out in the central field of Sculptor. Abundances have been measured for Fe, Mg, Ca, Si, and Ti with intermediate-resolution (IR) spectroscopy (Kirby et al. 2009) and high-resolution (HR) spectroscopy for ∼100 stars (Dwarf Abundances & Radialvelocities Team (DART) survey, Tolstoy et al. 2009; ...
RHIC - HIM
... What is (perturbative) QGP above Tc ? weakly interacting regime: weak running coupling. quarks are not locked into hadrons. quarks, antiquarks & gluons are proper ...
... What is (perturbative) QGP above Tc ? weakly interacting regime: weak running coupling. quarks are not locked into hadrons. quarks, antiquarks & gluons are proper ...
Excitation of the Hydrogen 21
... astronomical situations, and it is shown that in the usual situation collisions with H atoms are very effective in establishing the spin temperature equal to the kinetic temperature. Under conditions of low-density and/or high-radiation intensity, however, important deviations from the usual are not ...
... astronomical situations, and it is shown that in the usual situation collisions with H atoms are very effective in establishing the spin temperature equal to the kinetic temperature. Under conditions of low-density and/or high-radiation intensity, however, important deviations from the usual are not ...
Astronomy Astrophysics
... for comparison with observations. Wavelength scales were adjusted by cross correlating the observed and the synthetic spectra. The rotational profile (in the notation of Gray 1992) was used for the line broadening of the synthetic spectra and a limb darkening coefficient of = 0.15 following Pilachow ...
... for comparison with observations. Wavelength scales were adjusted by cross correlating the observed and the synthetic spectra. The rotational profile (in the notation of Gray 1992) was used for the line broadening of the synthetic spectra and a limb darkening coefficient of = 0.15 following Pilachow ...
Cataclysmic Variables
... these systems are extremely hot, which suggests that the high accretion rates observed during the high states probably prevail for thousands of years. A completely different picture is found among the magnetic CVs. If the white dwarf has a very high magnetic field (> 10 MG), the mass transfer stre ...
... these systems are extremely hot, which suggests that the high accretion rates observed during the high states probably prevail for thousands of years. A completely different picture is found among the magnetic CVs. If the white dwarf has a very high magnetic field (> 10 MG), the mass transfer stre ...
Notes for Class 14, April 21
... • I have the experiments in this course to: o Give you direct experience o Illustrate experiments described in class o Illustrate social nature of science within the lab ...
... • I have the experiments in this course to: o Give you direct experience o Illustrate experiments described in class o Illustrate social nature of science within the lab ...
Cosmic Evolution - University of Southern Maine
... nanometers across. (Red denotes oxygen atoms; blue, nitrogen; green, carbon; yellow, phosphorus; hydrogen is not shown.) Likewise, images of colorful globular star clusters (as at bottom left, where thousands of aged red giants dominate youthful blue stars) exemplify change-filled events in the earl ...
... nanometers across. (Red denotes oxygen atoms; blue, nitrogen; green, carbon; yellow, phosphorus; hydrogen is not shown.) Likewise, images of colorful globular star clusters (as at bottom left, where thousands of aged red giants dominate youthful blue stars) exemplify change-filled events in the earl ...
Nuclear Astrophysics
... For temperatures T < 100 MK, the beta decay lifetimes of 13N and 15O are much shorter compared to the lifetimes of 12C and 14N to destruction by protons. In other words, as soon as a 12C + p (or 14N + p) reaction creates 13N (15O) , the newly produced 13N (15O) basically decay before the next new 1 ...
... For temperatures T < 100 MK, the beta decay lifetimes of 13N and 15O are much shorter compared to the lifetimes of 12C and 14N to destruction by protons. In other words, as soon as a 12C + p (or 14N + p) reaction creates 13N (15O) , the newly produced 13N (15O) basically decay before the next new 1 ...
Title of Book: Deep Simplicity, John Gribbin Seven
... stripes in a bar code, and are just as individual; one particular pattern will unambiguously reveal the presence of iron, say, while others (more relevant in the present context) are associated with oxygen, or methane, or carbon dioxide. The French observations showed for the first time that the atm ...
... stripes in a bar code, and are just as individual; one particular pattern will unambiguously reveal the presence of iron, say, while others (more relevant in the present context) are associated with oxygen, or methane, or carbon dioxide. The French observations showed for the first time that the atm ...
Signals from the Beginnings of the World - Max-Planck
... have put forward at least 150 different theories – most of which have since been dismissed. The issue is further complicated by two sub-classes that were discovered through Compton measurements: gamma-ray bursts with a short duration of less than one to two seconds, and those that typically last bet ...
... have put forward at least 150 different theories – most of which have since been dismissed. The issue is further complicated by two sub-classes that were discovered through Compton measurements: gamma-ray bursts with a short duration of less than one to two seconds, and those that typically last bet ...
Wind-Blown Bubbles around Evolved Stars
... has left the main sequence. Direct observations of the stellar winds of massive stars can give information on the current mass-loss rates, while studies of the ring nebulae and HI shells that surround many Wolf-Rayet (WR) and luminous blue variable (LBV) stars provide information on the previous mas ...
... has left the main sequence. Direct observations of the stellar winds of massive stars can give information on the current mass-loss rates, while studies of the ring nebulae and HI shells that surround many Wolf-Rayet (WR) and luminous blue variable (LBV) stars provide information on the previous mas ...
New Double Stars from Asteroidal Occultations, 1971 - 2008
... Asteroids and planetary moons will naturally occult many stars as they move through the sky. The biggest challenge in observing such occultations is to accurately predict the time of the occultation event and the location of the shadow path as it crosses the Earth. Since the Hipparcos mission, and t ...
... Asteroids and planetary moons will naturally occult many stars as they move through the sky. The biggest challenge in observing such occultations is to accurately predict the time of the occultation event and the location of the shadow path as it crosses the Earth. Since the Hipparcos mission, and t ...
ASTRONOMY 113 Laboratory Lab 5: Spectral Classification of the
... determine its spectral type. If it hasn't already been catalogued (by the Harvard astronomers or the many who followed in their footsteps), then the classification must be done by taking a spectrum of the star and comparing it with an atlas of standard stars which provides examples of each spectral ...
... determine its spectral type. If it hasn't already been catalogued (by the Harvard astronomers or the many who followed in their footsteps), then the classification must be done by taking a spectrum of the star and comparing it with an atlas of standard stars which provides examples of each spectral ...
December - Rose City Astronomers
... scanty star grouping of DolidzeDžimšelejšvili 1 (Do-Dž 1). This triple star and open cluster combo is a remarkable stroke of cosmic serendipity in an area nearly devoid of other major deep-sky objects. The refractor at 44x shows the 12' diameter star cluster as six stars (9th to 11thmagnitude) embed ...
... scanty star grouping of DolidzeDžimšelejšvili 1 (Do-Dž 1). This triple star and open cluster combo is a remarkable stroke of cosmic serendipity in an area nearly devoid of other major deep-sky objects. The refractor at 44x shows the 12' diameter star cluster as six stars (9th to 11thmagnitude) embed ...
1 December 2014 An Update on the Universe Professor Ian Morison
... massive amount of energy. Half of the gravitational potential energy that arose from this inflationary period was converted into kinetic energy from which arose an almost identical number of particles and antiparticles, but with a very small excess of matter particles (~1 part in several billion). A ...
... massive amount of energy. Half of the gravitational potential energy that arose from this inflationary period was converted into kinetic energy from which arose an almost identical number of particles and antiparticles, but with a very small excess of matter particles (~1 part in several billion). A ...
properties and evolution of disks around pre-main
... Much progress in our knowledge of HAeBe stars has been made since the time of the Protostars and Planets III conference. Many results are summarized in the proceedings of the conference on HAeBe stars held in Amsterdam in 1993 (The´ et al. 1994b), and recent work has been cov´ ered in a number of re ...
... Much progress in our knowledge of HAeBe stars has been made since the time of the Protostars and Planets III conference. Many results are summarized in the proceedings of the conference on HAeBe stars held in Amsterdam in 1993 (The´ et al. 1994b), and recent work has been cov´ ered in a number of re ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.