3rd EXAM VERSION A key - Department of Physics and Astronomy
... D. The immense radiation output from the quasar carries away energy. The mass of the black hole gets smaller until it evaporates. 28. Observations indicate that blazers are A. quasars that have absorbed or merged with a smaller galaxy within a cluster B. distant spiral galaxies undergoing an intense ...
... D. The immense radiation output from the quasar carries away energy. The mass of the black hole gets smaller until it evaporates. 28. Observations indicate that blazers are A. quasars that have absorbed or merged with a smaller galaxy within a cluster B. distant spiral galaxies undergoing an intense ...
Active Galaxies
... •Emission lines from many ionization states •Nucleus does not dominate galaxy’s emission •Host galaxies are Elliptical/S0 Radio morphology first classified by Fanaroff & Riley (1974) •FR I: less luminous, 2-sided jets brightest closest to core and dominate over radio lobes •FR II: more luminous, edg ...
... •Emission lines from many ionization states •Nucleus does not dominate galaxy’s emission •Host galaxies are Elliptical/S0 Radio morphology first classified by Fanaroff & Riley (1974) •FR I: less luminous, 2-sided jets brightest closest to core and dominate over radio lobes •FR II: more luminous, edg ...
2.3 Peculiar galaxies
... the centre. Now imagine bringing another galaxy close. Our single star can then feel a force due to both galaxies. The net result is quite complicated, and whats more keeps changing with time, as the galaxies move closer. Rather than moving in a nice simple orbit, the stars do quite complex things. ...
... the centre. Now imagine bringing another galaxy close. Our single star can then feel a force due to both galaxies. The net result is quite complicated, and whats more keeps changing with time, as the galaxies move closer. Rather than moving in a nice simple orbit, the stars do quite complex things. ...
PH607 – Galaxies
... is such that the orbital speed of most stars in the galaxy does not depend strongly on its distance from the center. Away from the central bulge or outer rim, the typical stellar velocity is between 210 and 240 km/s. Hence the orbital period of the typical star is directly proportional only to the l ...
... is such that the orbital speed of most stars in the galaxy does not depend strongly on its distance from the center. Away from the central bulge or outer rim, the typical stellar velocity is between 210 and 240 km/s. Hence the orbital period of the typical star is directly proportional only to the l ...
Early Spring Observing – Millstone News Night Sky
... Although conspicuous and easily visible to the naked eye the cluster was not included in both the Messier or NGC catalogues due to its loose nature, large apparent size and unproven status as a genuine open cluster. It was only in 1938 that a study of 40 stellar members showed that these stars had ...
... Although conspicuous and easily visible to the naked eye the cluster was not included in both the Messier or NGC catalogues due to its loose nature, large apparent size and unproven status as a genuine open cluster. It was only in 1938 that a study of 40 stellar members showed that these stars had ...
M13 – The Great Hercules Cluster
... shaped like a flat, circular disk with a bulge at the center and arms that spiral around it like a pinwheel. On a clear, dark summer night in the country, you can see a pale glow arching overhead from South to North. This is just the glow of that disk of a hundred billion stars seen edge-on. When we ...
... shaped like a flat, circular disk with a bulge at the center and arms that spiral around it like a pinwheel. On a clear, dark summer night in the country, you can see a pale glow arching overhead from South to North. This is just the glow of that disk of a hundred billion stars seen edge-on. When we ...
Messier 87
Messier 87 (also known as Virgo A or NGC 4486, and generally abbreviated to M87) is a supergiant elliptical galaxy in the constellation Virgo. One of the most massive galaxies in the local universe, it is notable for its large population of globular clusters—M87 contains about 12,000 compared to the 150-200 orbiting the Milky Way—and its jet of energetic plasma that originates at the core and extends outward at least 1,500 parsecs (4,900 light-years), travelling at relativistic speed. It is one of the brightest radio sources in the sky, and is a popular target for both amateur astronomy observations and professional astronomy study.French astronomer Charles Messier discovered M87 in 1781, cataloguing it as a nebulous feature while searching for objects that would confuse comet hunters. The second brightest galaxy within the northern Virgo Cluster, M87 is located about 16.4 million parsecs (53.5 million light-years) from Earth. Unlike a disk-shaped spiral galaxy, M87 has no distinctive dust lanes. Instead, it has an almost featureless, ellipsoidal shape typical of most giant elliptical galaxies, diminishing in luminosity with distance from the centre. Forming around one sixth of M87's mass, the stars in this galaxy have a nearly spherically symmetric distribution, their density decreasing with increasing distance from the core. At the core is a supermassive black hole, which forms the primary component of an active galactic nucleus. This object is a strong source of multiwavelength radiation, particularly radio waves. M87's galactic envelope extends out to a radius of about 150 kiloparsecs (490,000 light-years), where it has been truncated—possibly by an encounter with another galaxy. Between the stars is a diffuse interstellar medium of gas that has been chemically enriched by elements emitted from evolved stars.