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Full-Text Articles in Stars, Interstellar Medium and the Galaxy

Statistical Analysis Of Stellar Evolution, David A. Van Dyk, Ted Von Hippel, Steven Degenarro, Nathan Stein, William Jefferys Aug 2019

Statistical Analysis Of Stellar Evolution, David A. Van Dyk, Ted Von Hippel, Steven Degenarro, Nathan Stein, William Jefferys

Ted von Hippel

Color-Magnitude Diagrams (CMDs) are plots that compare the magnitudes (luminosities) of stars in different wavelengths of light (colors). High nonlinear correlations among the mass, color, and surface temperature of newly formed stars induce a long narrow curved point cloud in a CMD known as the main sequence. Aging stars form new CMD groups of red giants and white dwarfs. The physical processes that govern this evolution can be described with mathematical models and explored using complex computer models. These calculations are designed to predict the plotted magnitudes as a function of parameters of scientific interest, such as stellar age, mass, …


Basic Astronomy Labs, Terry L. Smith, Michael D. Reynolds, Jay S. Huebner Jul 2014

Basic Astronomy Labs, Terry L. Smith, Michael D. Reynolds, Jay S. Huebner

Jay S Huebner

Providing the tools and know-how to apply the principles of astronomy first-hand, these 43 laboratory exercises each contain an introduction that clearly shows budding astronomers why the particular topic of that lab is of interest and relevant to astronomy. About one-third of the exercises are devoted solely to observation, and no mathematics is required beyond simple high school algebra and trigonometry.Organizes exercises into six major topics—sky, optics and spectroscopy, celestial mechanics, solar system, stellar properties, and exploration and other topics—providing clear outlines of what is involved in the exercise, its purpose, and what procedures and apparatus are to be used. …


Discovery Of A Massive Young Stellar Object In G10.47+0.27 By Way Of Meta Analysis Of Previously Published Data., Hontas F. Farmer Jul 2013

Discovery Of A Massive Young Stellar Object In G10.47+0.27 By Way Of Meta Analysis Of Previously Published Data., Hontas F. Farmer

Hontas F Farmer

We report the finding of a previously unidentified candidate massive young stellar object at the precise coordinates right ascension 18 08 38.2 and declination -19 51 50 in the region G10.47+0.27. This object was found by correlation of previously published data. At these coordinates the following key tracers of massive star formation are in a compact area; 4.5 micrometer infrared, a Class II methanol maser, two ionized hydrogen regions and three water masers. We also present a physical model of the disk and outflow in this region based on the morphology and kinematics of the methanol and water masers. Perhaps …


Insights Into High Mass Star Formation From Methanol Maser Observations., Hontas Freeman Farmer Jun 2013

Insights Into High Mass Star Formation From Methanol Maser Observations., Hontas Freeman Farmer

Hontas F Farmer

We present high angular resolution data on Class I and Class II methanol masers, together with other tracers of star formation like H2O masers, ultracompact (UC) ionized hydrogen (H II) regions, and 4.5 μm infrared sources, taken from the literature. The aim is to study what these data tell us about the process of high mass star formation; in particular, whether disk-outflow systems are compatible with the morphology exhibited by Class I and Class II methanol masers. Stars form in the dense cores inside molecular clouds, and while the process of the formation of stars like our Sun is reasonably …