Groups of Stars
... amounts of gas and dust to form new stars. They are spherical and have a dense concentration of stars in the center. Can contain more than a million stars. Usually do not have short-lived blue stars because these stars have already died out. Astronomers estimate that the oldest globular clust ...
... amounts of gas and dust to form new stars. They are spherical and have a dense concentration of stars in the center. Can contain more than a million stars. Usually do not have short-lived blue stars because these stars have already died out. Astronomers estimate that the oldest globular clust ...
Distant galaxies and quasars The ages of things Light
... estimate the total rate of star formation in the Universe (regardless which galaxies it is taking place in ... This, like the quasar evolution, shows a dramatic peak at earlier times ... but somewhat later than the quasars ...
... estimate the total rate of star formation in the Universe (regardless which galaxies it is taking place in ... This, like the quasar evolution, shows a dramatic peak at earlier times ... but somewhat later than the quasars ...
2.3 Peculiar galaxies
... Black hole accretion discs. If the available gas simply fell radially downwards towards the black hole, the energy it would gain would be kinetic energy, and it wouldn’t give much radiation; it would just disappear down the black hole. However, if, as is very likely, the gas is rotating around the b ...
... Black hole accretion discs. If the available gas simply fell radially downwards towards the black hole, the energy it would gain would be kinetic energy, and it wouldn’t give much radiation; it would just disappear down the black hole. However, if, as is very likely, the gas is rotating around the b ...
The extragalactic universe and distance measurements
... – Extended Messier’s list of nebula – Tried to determine distribution of stars in Milky Way – described Milky Way as “detached nebula”, with Sun near center. – Thought that the nebulae could be similar systems – Turns out that his conclusions were heavily effected by dust in the Milky Way – Milky Wa ...
... – Extended Messier’s list of nebula – Tried to determine distribution of stars in Milky Way – described Milky Way as “detached nebula”, with Sun near center. – Thought that the nebulae could be similar systems – Turns out that his conclusions were heavily effected by dust in the Milky Way – Milky Wa ...
Optics
... spectrum. Ultraviolet radiation begins just past the blue/violet region of the visible (optical) spectrum, and ends when X-rays take over. The boundaries between named regions can get a little blurred, especially if the broad-band regions (example: infrared) are further broken into sub-regions (exam ...
... spectrum. Ultraviolet radiation begins just past the blue/violet region of the visible (optical) spectrum, and ends when X-rays take over. The boundaries between named regions can get a little blurred, especially if the broad-band regions (example: infrared) are further broken into sub-regions (exam ...
Ch. 21 notes-1
... There are billions of galaxies in the universe. Astronomers have classified most galaxies into three main categories: spiral, elliptical and irregular. Spiral Galaxies A spiral galaxy is a galaxy that has the shape of twin spirals. They have arms that spiral outward, like pinwheels. The Milky Way ...
... There are billions of galaxies in the universe. Astronomers have classified most galaxies into three main categories: spiral, elliptical and irregular. Spiral Galaxies A spiral galaxy is a galaxy that has the shape of twin spirals. They have arms that spiral outward, like pinwheels. The Milky Way ...
chapter10
... The Deaths of Massive Stars: Supernovae Final stages of fusion in high-mass stars (> 8 Msun), leading to the formation of an iron core, happen extremely rapidly: Si burning lasts only for ~ 1 day. Iron core ultimately collapses, triggering an explosion that destroys the star: ...
... The Deaths of Massive Stars: Supernovae Final stages of fusion in high-mass stars (> 8 Msun), leading to the formation of an iron core, happen extremely rapidly: Si burning lasts only for ~ 1 day. Iron core ultimately collapses, triggering an explosion that destroys the star: ...
Word doc - UC-HiPACC - University of California, Santa Cruz
... explosion. The supermassive star Chen modeled had a radius of about 103 million miles—about 10% larger than Earth’s orbit—with a resolution of 30,000 miles, only 0.03% of the radius. Live fast, die young…leave no corpse The simulations revealed that a supermassive star burns hydrogen at a furious ra ...
... explosion. The supermassive star Chen modeled had a radius of about 103 million miles—about 10% larger than Earth’s orbit—with a resolution of 30,000 miles, only 0.03% of the radius. Live fast, die young…leave no corpse The simulations revealed that a supermassive star burns hydrogen at a furious ra ...
lecture25
... To study the structure of the Milky Way, we need to measure distances to stars There are well-tested methods for measuring distances over short length scales: ...
... To study the structure of the Milky Way, we need to measure distances to stars There are well-tested methods for measuring distances over short length scales: ...
Deep Space Mystery Note Form 3
... Small core of neutrons Spinning neutron star. Neutrons produce radio waves in a steady stream or random bursts. Stars 10 times the sun will leave a black hole. Leave behind a large core. With no energy fuse, it doesn’t have any out ward pressure so it gets engulfed in it’s own gravity an ...
... Small core of neutrons Spinning neutron star. Neutrons produce radio waves in a steady stream or random bursts. Stars 10 times the sun will leave a black hole. Leave behind a large core. With no energy fuse, it doesn’t have any out ward pressure so it gets engulfed in it’s own gravity an ...
Our Galaxy, the Milky Way Galaxy
... There is a super massive black hole at the center of our (and every other) galaxy that is maybe a billion solar masses Only important to find out how the stars near the center of a galaxy rotate We do not know where the black holes came from Black holes do not hold galaxies together and are light co ...
... There is a super massive black hole at the center of our (and every other) galaxy that is maybe a billion solar masses Only important to find out how the stars near the center of a galaxy rotate We do not know where the black holes came from Black holes do not hold galaxies together and are light co ...
Time From the Perspective of a Particle Physicist
... • if Mass(core) > 1.4 M(Sun) core collapses in SUPERNOVA (II) • leaves either Neutron Star or Black Hole • Most SN are this type PHYS 162 ...
... • if Mass(core) > 1.4 M(Sun) core collapses in SUPERNOVA (II) • leaves either Neutron Star or Black Hole • Most SN are this type PHYS 162 ...
Earth_Universe04
... • First one discovered in early 1970s • Pulsar (pulsating radio source) • Found in the Crab nebula (remnant of an A.D. 1054 supernova) ...
... • First one discovered in early 1970s • Pulsar (pulsating radio source) • Found in the Crab nebula (remnant of an A.D. 1054 supernova) ...
30galaxies and the universe
... Black holes in the centers of giant galaxies—some more than one billion solar masses—had enough infalling gas to once blaze as quasars. The final mass of a black hole is not primordial, but instead is determined during the galaxy formation process. This shows that there is a close relationship betwe ...
... Black holes in the centers of giant galaxies—some more than one billion solar masses—had enough infalling gas to once blaze as quasars. The final mass of a black hole is not primordial, but instead is determined during the galaxy formation process. This shows that there is a close relationship betwe ...
stargazing - davis.k12.ut.us
... heroines and beasts of their time and culture. Since those ancient times, people have continued to make up stories, develop religious practices and grow crops based on groups of stars. Groups of stars are called constellations, patterns of stars in the sky that have been identified and named. Some c ...
... heroines and beasts of their time and culture. Since those ancient times, people have continued to make up stories, develop religious practices and grow crops based on groups of stars. Groups of stars are called constellations, patterns of stars in the sky that have been identified and named. Some c ...
07-01TheColsmologicalDistanceLadder
... If you know the Earth-Mars distance, Kepler’s law RE3 = RM3 TE2 TM2 now lets you figure out the radius of Earth’s orbit. (Now we use radar to measure inter-orbit distances) ...
... If you know the Earth-Mars distance, Kepler’s law RE3 = RM3 TE2 TM2 now lets you figure out the radius of Earth’s orbit. (Now we use radar to measure inter-orbit distances) ...
Unit 3 - Section 9.7 2011 Universe Origin
... Scientifically, the size of a galaxy is estimated using, among other measures, luminosity. If I know an object’s luminosity, I can determine its mass. Yet, non-random discrepancies and errors occurred in the measurements. That is, the expected luminosity and the observed luminosity were slightly dif ...
... Scientifically, the size of a galaxy is estimated using, among other measures, luminosity. If I know an object’s luminosity, I can determine its mass. Yet, non-random discrepancies and errors occurred in the measurements. That is, the expected luminosity and the observed luminosity were slightly dif ...
Stellar Explosions
... A spiral galaxy approximately 2.5 million light-years away in the constellation Andromeda. It is the nearest spiral galaxy to our Milky Way Galaxy. It is also known as Messier 31, M31, and NGC 224. It was originally known as the Andromeda Nebula. ...
... A spiral galaxy approximately 2.5 million light-years away in the constellation Andromeda. It is the nearest spiral galaxy to our Milky Way Galaxy. It is also known as Messier 31, M31, and NGC 224. It was originally known as the Andromeda Nebula. ...
Activity 1 - Mathematical and Scientific Methods
... activities. Lowest 4 scores to be dropped. Math review counts as 2. ...
... activities. Lowest 4 scores to be dropped. Math review counts as 2. ...
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.