Sirius Astronomer - Orange County Astronomers
... HST has also found evidence for a cluster of young blue stars encircling one of the 1 st intermediate-mass black holes ever discovered. Small black holes (formed from a star collapsing) and supermassive black holes (found at the centers of most large galaxies) are both common. But intermediate-mass ...
... HST has also found evidence for a cluster of young blue stars encircling one of the 1 st intermediate-mass black holes ever discovered. Small black holes (formed from a star collapsing) and supermassive black holes (found at the centers of most large galaxies) are both common. But intermediate-mass ...
Presentation
... Stellar mass within the red galaxy population doubles. Star forming blue galaxies are being transformed. The most luminous galaxies were assembled at z>1. Some simulations overestimate z<1 galaxy assembly. ...
... Stellar mass within the red galaxy population doubles. Star forming blue galaxies are being transformed. The most luminous galaxies were assembled at z>1. Some simulations overestimate z<1 galaxy assembly. ...
Sloan Great Wall
... A process called gravitational lensing is able to prove the existence of dark matter process is used to measure the mass of a galaxy or galaxy cluster separation of the angles of the multiple images gives us mass of galaxy B If the mass derived is greater than visible mass then dark matter is presen ...
... A process called gravitational lensing is able to prove the existence of dark matter process is used to measure the mass of a galaxy or galaxy cluster separation of the angles of the multiple images gives us mass of galaxy B If the mass derived is greater than visible mass then dark matter is presen ...
public_lector_10
... The black hole itself is invisible, but we can measure its gravitational effect on nearby stars. Turbulence in the earth’s atmosphere blurs out any details smaller than about 0.5 arcsec (0.25 mm at 100 m). To see stars close enough to the black hole (0.1 arcsec), adaptive optics are needed to corre ...
... The black hole itself is invisible, but we can measure its gravitational effect on nearby stars. Turbulence in the earth’s atmosphere blurs out any details smaller than about 0.5 arcsec (0.25 mm at 100 m). To see stars close enough to the black hole (0.1 arcsec), adaptive optics are needed to corre ...
Where in the Milky Way Are We
... Part II: Mapping the Milky Way with Globular Clusters Galaxies like the Milky Way have objects, called “globular clusters” that exist in the outer regions of the galaxy (or halo). Globular clusters are dense clusters of stars that are generally free of gas and dust. In galaxies like the Milky Way, t ...
... Part II: Mapping the Milky Way with Globular Clusters Galaxies like the Milky Way have objects, called “globular clusters” that exist in the outer regions of the galaxy (or halo). Globular clusters are dense clusters of stars that are generally free of gas and dust. In galaxies like the Milky Way, t ...
Chapter 15, Galaxies
... around 1.0 M⊙, its luminosity is very consistent, and can be used as a standard candle for the measurement of distance to distant galaxies (Chapter 15). The amount of energy produced by white dwarf supernovae and massive star supernovae are about the same. But the properties of the light emitted fro ...
... around 1.0 M⊙, its luminosity is very consistent, and can be used as a standard candle for the measurement of distance to distant galaxies (Chapter 15). The amount of energy produced by white dwarf supernovae and massive star supernovae are about the same. But the properties of the light emitted fro ...
The Milky Way
... Dark – it doesn’t produce light (any kind) Does have mass, produces gravity Nature is unknown Might be normal matter in a form that doesn’t emit much light – very small and dim star, little black holes • More likely it is elementary particles other than normal matter ...
... Dark – it doesn’t produce light (any kind) Does have mass, produces gravity Nature is unknown Might be normal matter in a form that doesn’t emit much light – very small and dim star, little black holes • More likely it is elementary particles other than normal matter ...
Summary Of the Structure of the Milky Way
... • The Distribution of stars can reveal part of the disk-like nature of the Milky Way galaxy, but are not “deep” enough probes to fully reveal the structure of the Milky Way. • Open clusters can define the thickness of the Milky Way’s thin disk where star formation is active. • Globular clusters allo ...
... • The Distribution of stars can reveal part of the disk-like nature of the Milky Way galaxy, but are not “deep” enough probes to fully reveal the structure of the Milky Way. • Open clusters can define the thickness of the Milky Way’s thin disk where star formation is active. • Globular clusters allo ...
Lecture 32 Quasars
... – A typical quasar has a luminosity 100 times as large as the Milky Way's luminosity. – Because of luminosity and distance, observing quasars can tell us about the intergalactic medium (IGM) between us and the source. Apr 12, 2006 ...
... – A typical quasar has a luminosity 100 times as large as the Milky Way's luminosity. – Because of luminosity and distance, observing quasars can tell us about the intergalactic medium (IGM) between us and the source. Apr 12, 2006 ...
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.