Clusters of galaxies
... ESO Distant Cluster Survey Identification, deep photometry and spectroscopy of 10 clusters around z ~ 0.5 and 10 around z ~ 0.8 Spectroscopy is FORS2 (R ~ 1200) Science goals are build up of stellar populations with redshift (plus weak lensing). ...
... ESO Distant Cluster Survey Identification, deep photometry and spectroscopy of 10 clusters around z ~ 0.5 and 10 around z ~ 0.8 Spectroscopy is FORS2 (R ~ 1200) Science goals are build up of stellar populations with redshift (plus weak lensing). ...
25.2 Stellar Evolution
... The Milky Way is a large spiral galaxy whose disk is about 100,000 light-years wide and about 10,000 light-years thick at the nucleus, as shown in Figure 17A. Our solar system orbits the galactic ...
... The Milky Way is a large spiral galaxy whose disk is about 100,000 light-years wide and about 10,000 light-years thick at the nucleus, as shown in Figure 17A. Our solar system orbits the galactic ...
E:\2012-2013\SSU\PHS 207spring 2013\3rd test 4
... The younger stars contain heavier elements created in massive stars and gathered from the supernovae of those stars. The older stars were created before the supernovae released the heavier elements. ...
... The younger stars contain heavier elements created in massive stars and gathered from the supernovae of those stars. The older stars were created before the supernovae released the heavier elements. ...
PH607 – Galaxies
... billion (109) years, which is nearly as old as the Universe itself. This estimate is based on Very Large Telescope measurements of the beryllium content of two stars in globular cluster NGC 6397. This allowed astronomers to deduce the elapsed time between the rise of the first generation of stars in ...
... billion (109) years, which is nearly as old as the Universe itself. This estimate is based on Very Large Telescope measurements of the beryllium content of two stars in globular cluster NGC 6397. This allowed astronomers to deduce the elapsed time between the rise of the first generation of stars in ...
GAIA Composition, Formation and Evolution of our Galaxy
... ⇒ every star in the Galaxy and Local Group will be seen to move ⇒ GAIA will quantify 6-D phase space for over 300 million stars, and 5-D phase-space for over 109 stars And an interesting data reduction challenge…. ...
... ⇒ every star in the Galaxy and Local Group will be seen to move ⇒ GAIA will quantify 6-D phase space for over 300 million stars, and 5-D phase-space for over 109 stars And an interesting data reduction challenge…. ...
Lecture Notes – Galaxies
... Galaxies were first systematically categorized by Edwin Hubble who in 1929 classified them according to shape: the Hubble Classification Scheme or Tuning Fork Diagram Elliptical galaxies (‘Early type’) E0 – E7 (0 spherical, 7 most distorted): S0 These galaxies are intermediate between E0 and Sa – th ...
... Galaxies were first systematically categorized by Edwin Hubble who in 1929 classified them according to shape: the Hubble Classification Scheme or Tuning Fork Diagram Elliptical galaxies (‘Early type’) E0 – E7 (0 spherical, 7 most distorted): S0 These galaxies are intermediate between E0 and Sa – th ...
www.univ-amu.fr www.lam.fr PhD Thesis PhD thesis director name
... several minutes, the radiation emitted in this interval is equivalent to that of the Sun over its entire life. They are hundreds of times brighter than a typical supernova, the ultimate end of a massive star. Due to the extreme luminosity of their multi-wavelength emissions, they are now considered ...
... several minutes, the radiation emitted in this interval is equivalent to that of the Sun over its entire life. They are hundreds of times brighter than a typical supernova, the ultimate end of a massive star. Due to the extreme luminosity of their multi-wavelength emissions, they are now considered ...
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.