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L10 - QUB Astrophysics Research Centre
L10 - QUB Astrophysics Research Centre

... The existence of a superwind is suggested by two independent variables. The high density observed within the observed shells in stellar ejecta, and relative paucity of very bright stars on the AGB. The latter (Prialnik P. 161) comes from the number of AGB stars expected compared to observed is >10. ...
Basics of chemical evolution
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Distances
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... in star clusters), the absolute distance to a pulsating variable star can be estimated by the BaadeWesselink method. This technique employs high-resolution spectroscopy to measure the variation of a star’s radial velocity as it expands and contracts. The time integral of the velocity gives the absol ...
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Planetary Configurations

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PPT
PPT

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astro2_lec1 - Astronomy & Astrophysics Group
astro2_lec1 - Astronomy & Astrophysics Group

... o Leavitt studied Cepheids in the Large Magellanic Cloud, a satellite galaxy of the Milky Way and known even then to be very distant. o Differences in apparent brightness of LMC Cepheids must be due to differences in intrinsic ...
HR Diagram Lab Handout
HR Diagram Lab Handout

... Russell Diagram. Background: You are about to create your own HR Diagram, a chart that revolutionized the study of stars. You will have a labeled chart and a series of points to plot. From these points, you can deduce a lot of information about stars! Please read the directions in each step of the a ...
Stellar Luminosity and Mass Functions * * * * * History and
Stellar Luminosity and Mass Functions * * * * * History and

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Astronomy (C) - North Carolina Science Olympiad
Astronomy (C) - North Carolina Science Olympiad

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Lecture102802 - FSU High Energy Physics
Lecture102802 - FSU High Energy Physics

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The solar system rotates around the sun due to the sun`s

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R and FUV Observations of Star Formation in

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Death of High Mass Stars
Death of High Mass Stars

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Linking Asteroids and Meteorites through Reflectance Spectroscopy
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Opakování z minulého cvičení

... One of the minor constituents of the Solar System, a comet is a lump of icy material and dust (perhaps several lumps moving together), which becomes visible if it approaches the Sun. The heat of the Sun makes material evaporate from the comet, forming a cloudy coma around the Icy nucleus and a strea ...
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Beyond the Solar System Homework for Geology 8

... 20. A collection or cluster of stars and solar systems such as the Milky Way or Andromeda. 21. This type of nebula is a cloud of glowing gas excited by ultraviolet radiation from hot stars. ...
Stellar Evolution (Formation)
Stellar Evolution (Formation)

... Example: in the dense core of a typical giant molecular cloud: T~ 10 K;  ~ 3 x 10-17 kg/m3;  ~ 2 for pure H2 gas (X= 1, Y = Z = 0) Thus MJ ~ 2 Msun The characteristic mass of these dense cores is ~ 10 Msun so they are unstable to gravitational collapse - consistent with them being sites of star fo ...
June 2016 - Flint River Astronomy Club
June 2016 - Flint River Astronomy Club

... Neutron stars emit radiation from their magnetic poles. That radiation can be detected by x-ray, infrared and visual means. When a neutron star’s magnetic poles and axis of rotation are aligned, the radiation emission is constant. In some cases, however, a neutron star’s magnetic poles are not align ...
Test 1 - Brock physics
Test 1 - Brock physics

... 5. Dark nebulae appear dark because they contain a large amount of (a) dark matter. (b) dust. (c) nebulinos. (d) helium. 6. Emission nebulae appear (a) yellow, because they emit a significant amount of yellow electromagnetic radiation. (b) blue, because they emit a significant amount of blue and ult ...
An analogy
An analogy

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A105 Stars and Galaxies

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MT 2 Answers Version C
MT 2 Answers Version C

... dropped from the same height and allowed to fall to the ground. How do their accelerations compare? (a) ...
MT 2 Answers Version A
MT 2 Answers Version A

... mostly at the poles that lie along the cloud’s axis of rotation. ...
MT 2 Answers Version D
MT 2 Answers Version D

... 31. Examine the figure below. On a typical H-R diagram, what are the stars that have the hottest surface temperatures and the smallest radii? ...
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H II region



An H II region is a large, low-density cloud of partially ionized gas in which star formation has recently taken place. The short-lived blue stars forged in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. The first known H II region was the Orion Nebula, which was discovered in 1610 by Nicolas-Claude Fabri de Peiresc.H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II, pronounced H-two by astronomers (an H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). Such regions have extremely diverse shapes, because the distribution of the stars and gas inside them is irregular. They often appear clumpy and filamentary, sometimes showing bizarre shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster of birthed stars such as the Pleiades.H II regions can be seen to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies. Spiral and irregular galaxies contain many H II regions, while elliptical galaxies are almost devoid of them. In the spiral galaxies, including the Milky Way, H II regions are concentrated in the spiral arms, while in the irregular galaxies they are distributed chaotically. Some galaxies contain huge H II regions, which may contain tens of thousands of stars. Examples include the 30 Doradus region in the Large Magellanic Cloud and NGC 604 in the Triangulum Galaxy.
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