Chapter 26: Stars, Galaxies, and the Universe Stars
... collapse shrinks the star's core to a white, glowing object about the size of Earth. A star at this point is called a white dwarf. Eventually, a white dwarf cools down and its light fades out. Supergiants and Supernovas A star that has much more mass than the Sun will end its life in a more dramatic ...
... collapse shrinks the star's core to a white, glowing object about the size of Earth. A star at this point is called a white dwarf. Eventually, a white dwarf cools down and its light fades out. Supergiants and Supernovas A star that has much more mass than the Sun will end its life in a more dramatic ...
The Essential Cosmic Perspective, 6e
... 2) Briefly explain what we mean by the statement "The farther away we look in distance, the further back we look in time." Answer: It means that when we look at a distant object, we see it as it was some time in the past, rather than as it is now. This is because the light we see has taken time to t ...
... 2) Briefly explain what we mean by the statement "The farther away we look in distance, the further back we look in time." Answer: It means that when we look at a distant object, we see it as it was some time in the past, rather than as it is now. This is because the light we see has taken time to t ...
the magellanic clouds newsletter - Keele University Astrophysics
... The two Large Magellanic Cloud star clusters NGC 1805 and NGC 1818 are approximately the same chronological age (∼ 30 Myr), but show different radial trends in binary frequency. The F-type stars (1.3–2.2 M⊙ ) in NGC 1818 have a binary frequency that decreases towards the core, while the binary frequ ...
... The two Large Magellanic Cloud star clusters NGC 1805 and NGC 1818 are approximately the same chronological age (∼ 30 Myr), but show different radial trends in binary frequency. The F-type stars (1.3–2.2 M⊙ ) in NGC 1818 have a binary frequency that decreases towards the core, while the binary frequ ...
The Milky Way Galaxy
... The energy for the state where the spins are parallel is higher than for the state where the spins are anti-parallel The hydrogen atom, if it is in the spin parallel state, can make a transition to the spin anti-parallel state releasing energy When a transition does a occur, energy is released corre ...
... The energy for the state where the spins are parallel is higher than for the state where the spins are anti-parallel The hydrogen atom, if it is in the spin parallel state, can make a transition to the spin anti-parallel state releasing energy When a transition does a occur, energy is released corre ...
PDF format
... more compact than a white dwarf. b) True, neutron stars had been observed before at optical wavelengths but it was only after they were found to pulsate at radio wavelengths that astronomers realized their nature. c) False, the existence of neutron stars was predicted by theory and it was widely a ...
... more compact than a white dwarf. b) True, neutron stars had been observed before at optical wavelengths but it was only after they were found to pulsate at radio wavelengths that astronomers realized their nature. c) False, the existence of neutron stars was predicted by theory and it was widely a ...
The formation of the galaxy is believed to be similar
... One model for the formation of the Milky Way can be divided into 2 phases: a spherical gas cloud (halo) collapsed to form the stars in the Milky Way's ...
... One model for the formation of the Milky Way can be divided into 2 phases: a spherical gas cloud (halo) collapsed to form the stars in the Milky Way's ...
flare swg usa
... Large telescope for point source sensitivity 2) Large-Scale Patterns in the Background Small telescope with fidelity on degree scales → the amplitude of large-scale (clustering) fluctuations proportional to total light production ...
... Large telescope for point source sensitivity 2) Large-Scale Patterns in the Background Small telescope with fidelity on degree scales → the amplitude of large-scale (clustering) fluctuations proportional to total light production ...
PPT
... • How do we measure the distances to galaxies? – The distance-measurement chain begins with parallax measurements that build on radar ranging in our solar system – Using parallax and the relationship between luminosity, distance, and brightness, we can calibrate a series of standard candles – We can ...
... • How do we measure the distances to galaxies? – The distance-measurement chain begins with parallax measurements that build on radar ranging in our solar system – Using parallax and the relationship between luminosity, distance, and brightness, we can calibrate a series of standard candles – We can ...
CHP 15
... b. gas in the spiral arms is hot enough to emit photons. c. dust in spiral arms is more dense than it is between the spiral arms. d. gas in spiral arms is more dense than it is between the spiral arms. e. stars in the spiral arms emit most of their energy at radio wavelengths. If the spiral density ...
... b. gas in the spiral arms is hot enough to emit photons. c. dust in spiral arms is more dense than it is between the spiral arms. d. gas in spiral arms is more dense than it is between the spiral arms. e. stars in the spiral arms emit most of their energy at radio wavelengths. If the spiral density ...
telescope
... The famous 100 inch (2.5 m) Hooker telescope at Mount Wilson Observatory near Los Angeles, California was one of the early reflecting telescopes of the 20th century. This is the telescope that Edwin Hubble used to measure galaxy redshifts. This led to the discovery that the Universe is expanding and ...
... The famous 100 inch (2.5 m) Hooker telescope at Mount Wilson Observatory near Los Angeles, California was one of the early reflecting telescopes of the 20th century. This is the telescope that Edwin Hubble used to measure galaxy redshifts. This led to the discovery that the Universe is expanding and ...
Part2
... How to make a good guess at LCO? o We’ve already seen that many galaxy properties are strongly covariant with one another. This include CO luminosity. o Both stellar luminosity and infrared luminosity (or some other tracer of star formation rate) are good places to start. ...
... How to make a good guess at LCO? o We’ve already seen that many galaxy properties are strongly covariant with one another. This include CO luminosity. o Both stellar luminosity and infrared luminosity (or some other tracer of star formation rate) are good places to start. ...
PPS
... Final evolutionary stages. White dwarfs, neutron stars, black holes. Variable stars. Cepheids. Novae and supernovae stars. Binary systems. Other galactic and extragalactic objects, nebulae, star clusters, galaxies. ...
... Final evolutionary stages. White dwarfs, neutron stars, black holes. Variable stars. Cepheids. Novae and supernovae stars. Binary systems. Other galactic and extragalactic objects, nebulae, star clusters, galaxies. ...
arXiv:1502.04693v1 [gr
... performance if no model of the CIB spectra is assumed, and instead the CIB spectra are marginalized over, when constraining r. We find that such uncertainty does not significantly affect B-mode surveys smaller than a few thousand degrees. Even for larger surveys it causes only a moderate reduction i ...
... performance if no model of the CIB spectra is assumed, and instead the CIB spectra are marginalized over, when constraining r. We find that such uncertainty does not significantly affect B-mode surveys smaller than a few thousand degrees. Even for larger surveys it causes only a moderate reduction i ...
Exploration of the Milky Way and Nearby galaxies
... peculiar abundance ratios, will provide useful constraints on the existence or fraction of very massive stars in the early universe (Karlsson et al. 2008). High resolution spectra for such studies can be obtained witth TMT/HROS. ...
... peculiar abundance ratios, will provide useful constraints on the existence or fraction of very massive stars in the early universe (Karlsson et al. 2008). High resolution spectra for such studies can be obtained witth TMT/HROS. ...
THE DAWN OF X-RAY ASTRONOMY
... and MIT groups. These observations clarified that the observed pulsations were not periodic but chaotic (Holt et al., 1971)16 (Rappaport et al., 1971).17 By 1974, the GSFC group had achieved a temporal resolution of 1 millisecond and showed large chaotic fluctuations occurring even on this time scal ...
... and MIT groups. These observations clarified that the observed pulsations were not periodic but chaotic (Holt et al., 1971)16 (Rappaport et al., 1971).17 By 1974, the GSFC group had achieved a temporal resolution of 1 millisecond and showed large chaotic fluctuations occurring even on this time scal ...
... around 280 parts per million (ppm) to around 380 ppm now. Studies of ice core show that concentrations of CO2 have not been so high for nearly half a million years. At the current rate of increase, they will have reached 800 ppm by the end of the 21st century! Beyond 550 ppm it would not be liveable ...
The Sculptor dwarf irregular galaxy SDIG: present and past
... SDIG lies near the South Galactic Pole, so the galactic extinction is small. Laustsen et al. (1977) adopted a colour excess of 0 mag, whereas LW81 suggested that the colour excess for SDIG should be similar to the colour excess of the Sculptor dwarf spheroidal, for which studies of the colourmagnitu ...
... SDIG lies near the South Galactic Pole, so the galactic extinction is small. Laustsen et al. (1977) adopted a colour excess of 0 mag, whereas LW81 suggested that the colour excess for SDIG should be similar to the colour excess of the Sculptor dwarf spheroidal, for which studies of the colourmagnitu ...
SUMSS - 京都大学
... What are the “high SFR” galaxies? • Radio LF for star-forming galaxies implies that galaxies with SFR > 30 Msun/yr are far more common than Ha surveys suggest, and may account for up to 40% of the local star-formation density. • Dust obscuration in star-forming regions could lead to under-estimate ...
... What are the “high SFR” galaxies? • Radio LF for star-forming galaxies implies that galaxies with SFR > 30 Msun/yr are far more common than Ha surveys suggest, and may account for up to 40% of the local star-formation density. • Dust obscuration in star-forming regions could lead to under-estimate ...
Gamma-ray burst
Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several hours. The initial burst is usually followed by a longer-lived ""afterglow"" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the ""short"" bursts) appear to originate from a different process – this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years). All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way. It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.GRBs were first detected in 1967 by the Vela satellites, a series of satellites designed to detect covert nuclear weapons tests. Hundreds of theoretical models were proposed to explain these bursts in the years following their discovery, such as collisions between comets and neutron stars. Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs. These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs. These facts definitively placed them in distant galaxies and also connected long GRBs with the explosion of massive stars, the only possible source for the energy outputs observed.