AMNH_colloquium_2May07_v7b
... •The f/i line ratios are consistent with this spatial distribution •The line profile shapes are also consistent with this distribution (as already was shown for single, unblended lines) ...
... •The f/i line ratios are consistent with this spatial distribution •The line profile shapes are also consistent with this distribution (as already was shown for single, unblended lines) ...
printer-friendly version of benchmark
... 2. Students have a misconception that nighttime visible stars are located within our solar system. Such a notion has been considered since the times of the ancient Greeks. Aristotle proposed a geocentric model of the solar system with Earth at the center. Crystalline spheres surrounded Earth. Each o ...
... 2. Students have a misconception that nighttime visible stars are located within our solar system. Such a notion has been considered since the times of the ancient Greeks. Aristotle proposed a geocentric model of the solar system with Earth at the center. Crystalline spheres surrounded Earth. Each o ...
Stories in the Stars
... originally labeled as nebulae are now known in include galaxies (Andromeda is one), clouds of gas and dust (Orion nebula), and supernova remnants (Crab nebula). Nova. Latin for “new,” the sudden appearance of a star where none had previously been known. Sudden brightening of a star, followed by a le ...
... originally labeled as nebulae are now known in include galaxies (Andromeda is one), clouds of gas and dust (Orion nebula), and supernova remnants (Crab nebula). Nova. Latin for “new,” the sudden appearance of a star where none had previously been known. Sudden brightening of a star, followed by a le ...
– 1 – 1. Chemical Evolution 1.1.
... suggests that the Salpeter IMF is too steep to fit the observations for low mass stars below 0.5M⊙ , and that a flatter slope is required, reaching −0.3 ± 0.7 for 0.01 < M/M⊙ < 0.08. Note that the transformation from luminosity to mass (the IMF is a function of stellar mass) is not as well determine ...
... suggests that the Salpeter IMF is too steep to fit the observations for low mass stars below 0.5M⊙ , and that a flatter slope is required, reaching −0.3 ± 0.7 for 0.01 < M/M⊙ < 0.08. Note that the transformation from luminosity to mass (the IMF is a function of stellar mass) is not as well determine ...
17 April 2013 When Galaxies Collide Professor Carolin Crawford
... The bulge is a yellowy-white colour, revealing that it is an accumulation of older stars, similar to the population found in an elliptical galaxy. The spiral arms within the disc are notably much bluer, as they trace regions where massive star formation is currently active (blue stars are short-liv ...
... The bulge is a yellowy-white colour, revealing that it is an accumulation of older stars, similar to the population found in an elliptical galaxy. The spiral arms within the disc are notably much bluer, as they trace regions where massive star formation is currently active (blue stars are short-liv ...
norfolk skies - Norfolk Astronomical Society
... On a cold night last January (1980), Dr. Scarr and I stumbled onto a beautiful little cluster of stars, just south of Sirius, in the constellation pf Canis Major. It's a very impressive little group, with about 3040 little 10th magnitude stars, all bunched up around this bright 4th magnitude star. A ...
... On a cold night last January (1980), Dr. Scarr and I stumbled onto a beautiful little cluster of stars, just south of Sirius, in the constellation pf Canis Major. It's a very impressive little group, with about 3040 little 10th magnitude stars, all bunched up around this bright 4th magnitude star. A ...
BASIC PROPERTIES of STARS - 2
... With a Sun-centered Solar System and a moving Earth, objects outside the Solar System can potentially exhibit parallax. Whether we can measure it will depend on their distance. Tycho Brahe looked for parallax of the stars in the 1570’s as proof of the Copernican Theory. Did not see it - concluded th ...
... With a Sun-centered Solar System and a moving Earth, objects outside the Solar System can potentially exhibit parallax. Whether we can measure it will depend on their distance. Tycho Brahe looked for parallax of the stars in the 1570’s as proof of the Copernican Theory. Did not see it - concluded th ...
A Tour of the Radio Universe
... the sharp Hubble images. Most of the pale, white objects sprinkled around the body of M82 that look like fuzzy stars are actually individual star clusters about 20 light-years across and contain up to a million stars. The rapid rate of star formation in this galaxy eventually will be self-limiting. ...
... the sharp Hubble images. Most of the pale, white objects sprinkled around the body of M82 that look like fuzzy stars are actually individual star clusters about 20 light-years across and contain up to a million stars. The rapid rate of star formation in this galaxy eventually will be self-limiting. ...
H-Band spectroscopic classification of OB stars
... standard star which had first been corrected for intrinsic H absorption lines (Pβ 1.281 µm, and Brackett series 1.51 µm to 2.165 µm). The atmospheric standards were observed in pairs of A–type and G–type stars. The H lines in the A stars were corrected in the following way. The majority (seven) of o ...
... standard star which had first been corrected for intrinsic H absorption lines (Pβ 1.281 µm, and Brackett series 1.51 µm to 2.165 µm). The atmospheric standards were observed in pairs of A–type and G–type stars. The H lines in the A stars were corrected in the following way. The majority (seven) of o ...
High resolution spectroscopy: what`s next?
... The chemical composition of stars in local galaxies The most metal poor stars in our Galaxy as fossil records of PopIII stars Stellar oscillations, asteroseismology and variability The nature of galactic winds constrained with tomography of small fields with close quasar lines of sight The physical ...
... The chemical composition of stars in local galaxies The most metal poor stars in our Galaxy as fossil records of PopIII stars Stellar oscillations, asteroseismology and variability The nature of galactic winds constrained with tomography of small fields with close quasar lines of sight The physical ...
Altair - the hottest `cool` star in X-rays
... 2.4 MK and its emission measure distribution (EMD) is dominated by rather cool plasma at temperatures in the range of 1 – 4 MK, additionally a weak hotter component seems to contribute at a few percent level. These properties are quite typical for weakly active stars and similar to those of the quie ...
... 2.4 MK and its emission measure distribution (EMD) is dominated by rather cool plasma at temperatures in the range of 1 – 4 MK, additionally a weak hotter component seems to contribute at a few percent level. These properties are quite typical for weakly active stars and similar to those of the quie ...
Surveying the Stars
... • How hot are stars? • The surface temperatures of the hottest stars exceed 40,000 K and those of the coolest stars are less than 3,000 K. We measure a star’s surface temperature from its color or spectrum, and we classify spectra according to the sequence of spectral types ...
... • How hot are stars? • The surface temperatures of the hottest stars exceed 40,000 K and those of the coolest stars are less than 3,000 K. We measure a star’s surface temperature from its color or spectrum, and we classify spectra according to the sequence of spectral types ...
The Rigel Star - Emmi
... • Rigel is the ankle in the constellation Orion, a hunter from the Greek myths. • Orion was a great hunter and honest man. Because of this, he became the companion of Artemis, goddess of the hunt. This made Artemis’ twin, Apollo, jealous and he sent an enormous scorpion to sting Orion. Artemis was a ...
... • Rigel is the ankle in the constellation Orion, a hunter from the Greek myths. • Orion was a great hunter and honest man. Because of this, he became the companion of Artemis, goddess of the hunt. This made Artemis’ twin, Apollo, jealous and he sent an enormous scorpion to sting Orion. Artemis was a ...
october 2008 - Mahoning Valley Astronomical Society
... try for the brightest-- go for G1. Also known as Mayall II or Andromeda's Globular, it was discovered in 1953 by the astronomers Nicholas Mayall and Olin J. Eggen. G1 consists of 300,000 to 1 million old stars. It lies about 130,000 light years away from its home galaxy M31. From our perspective thi ...
... try for the brightest-- go for G1. Also known as Mayall II or Andromeda's Globular, it was discovered in 1953 by the astronomers Nicholas Mayall and Olin J. Eggen. G1 consists of 300,000 to 1 million old stars. It lies about 130,000 light years away from its home galaxy M31. From our perspective thi ...
Stars Part 1
... Two 3He nuclei may eventually (within ten thousand years) find each other. 3He ...
... Two 3He nuclei may eventually (within ten thousand years) find each other. 3He ...
Document
... Venn & Lambert (2008) have argued that this may not be the case. Peculiar stars such as post AGB stars and l Boo stars have iron abundances as low as [Fe/H] ~ –5. These are thought to be due to the separation of gas and dust beyond the stellar surface followed by an accretion of the dust-depleted g ...
... Venn & Lambert (2008) have argued that this may not be the case. Peculiar stars such as post AGB stars and l Boo stars have iron abundances as low as [Fe/H] ~ –5. These are thought to be due to the separation of gas and dust beyond the stellar surface followed by an accretion of the dust-depleted g ...
Stars part 1
... 2. Luminosity – the total amount of energy a star radiates each second. Luminosity of all visible stars range from 1/1,000,000 the luminosity of the sun to 1,000,000 time the luminosity of the sun. 90% of the stars are not as bright as the sun. ...
... 2. Luminosity – the total amount of energy a star radiates each second. Luminosity of all visible stars range from 1/1,000,000 the luminosity of the sun to 1,000,000 time the luminosity of the sun. 90% of the stars are not as bright as the sun. ...
Order-of-Magnitude Astrophysics
... 37. Consider a star near the Chandrasekhar mass limit, in which particles of mass m1 are supported by the degeneracy pressure of particles (similar in number) of mass m2 . (e.g., for a carbon white dwarf, m1 is the mass of a carbon nucleus and m2 is the mass of an electron; for a neutron star m1 and ...
... 37. Consider a star near the Chandrasekhar mass limit, in which particles of mass m1 are supported by the degeneracy pressure of particles (similar in number) of mass m2 . (e.g., for a carbon white dwarf, m1 is the mass of a carbon nucleus and m2 is the mass of an electron; for a neutron star m1 and ...
Zinc and chromium abundances in a third
... surface brightness and low metallicity ([Zn/H] = −1.21), consistent with the reduced star formation efficiencies typical of such galaxies (McGaugh 1994). The latter also has a relatively low abundance, [Zn/H] = −0.85, and a rest frame B-band absolute magnitude, MB ' −19.5, corresponding to ≈ 0.25L∗ ...
... surface brightness and low metallicity ([Zn/H] = −1.21), consistent with the reduced star formation efficiencies typical of such galaxies (McGaugh 1994). The latter also has a relatively low abundance, [Zn/H] = −0.85, and a rest frame B-band absolute magnitude, MB ' −19.5, corresponding to ≈ 0.25L∗ ...
The Stars education kit - Student activities 5-10
... Betelgeuse is a red supergiant star in the constellation of Orion. The surface temperature of Betelgeuse is approximately 3000 degrees Celsius. Its diameter fluctuates in size from about 300 to 400 times the Sun’s diameter. It is estimated to be about 427 light years away. Aldebaran is a red giant s ...
... Betelgeuse is a red supergiant star in the constellation of Orion. The surface temperature of Betelgeuse is approximately 3000 degrees Celsius. Its diameter fluctuates in size from about 300 to 400 times the Sun’s diameter. It is estimated to be about 427 light years away. Aldebaran is a red giant s ...
apparent magnitude - Harding University
... In addition to the spectral classification OBAFGKM, which is related closely to temperature, astronomers have subdivide stellar spectra into luminosity classes which are related more to the size (or surface density) of a star. For example, a B8 supergiant spectra exhibits narrower spectral lines tha ...
... In addition to the spectral classification OBAFGKM, which is related closely to temperature, astronomers have subdivide stellar spectra into luminosity classes which are related more to the size (or surface density) of a star. For example, a B8 supergiant spectra exhibits narrower spectral lines tha ...
CONSTELLATIONS OF THE SOUTHERN SKY VOLANS
... Created by Bayer in 1603, this constellation used to be called PiscisVolans, the Flying Fish, before it was shortened to Volans. Volans was one of the 12 new constellations introduced at the end of the 16th century by the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman. Volans repr ...
... Created by Bayer in 1603, this constellation used to be called PiscisVolans, the Flying Fish, before it was shortened to Volans. Volans was one of the 12 new constellations introduced at the end of the 16th century by the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman. Volans repr ...
J: Chapter 4: Stars and Galaxies
... How do scientists determine distance to stars from the solar system that Earth is part of? One way is to measure its parallax—the apparent shift in the position of an object when viewed from two different positions. Extend your arm and look at your thumb first with your left eye closed and then with ...
... How do scientists determine distance to stars from the solar system that Earth is part of? One way is to measure its parallax—the apparent shift in the position of an object when viewed from two different positions. Extend your arm and look at your thumb first with your left eye closed and then with ...
Some Introductory Physics of Sound
... We characterise waves in a number of ways, the simplest of which is the wavelength, measured as the distance between two successive compressions or rarefactions. We also use the term frequency, particularly in the case of sound, to specify an exact note being heard, as it tells how densely packed th ...
... We characterise waves in a number of ways, the simplest of which is the wavelength, measured as the distance between two successive compressions or rarefactions. We also use the term frequency, particularly in the case of sound, to specify an exact note being heard, as it tells how densely packed th ...
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.