Die Sonne im Röntgenlicht
... early-type disk galaxies • For NGC 4594, hot gas radiative cooling rate ~ 2% of the energy input from Type Ia SNe alone • Not much cool gas to hide or convert the SN energy • Mass and metals are also missing! – Mass input rate of evolved stars ...
... early-type disk galaxies • For NGC 4594, hot gas radiative cooling rate ~ 2% of the energy input from Type Ia SNe alone • Not much cool gas to hide or convert the SN energy • Mass and metals are also missing! – Mass input rate of evolved stars ...
Elliptical galaxies
... •The spectrum of an E galaxy resembles that of a K giant star. •E galaxies appear generally red: •very few stars made in the last 1-2 Gyr (recall that after 1 Gyr, only stars with masses < 2 M¯ are still on the main sequence) •Most of the light is emitted while stars are on the giant branch •The sta ...
... •The spectrum of an E galaxy resembles that of a K giant star. •E galaxies appear generally red: •very few stars made in the last 1-2 Gyr (recall that after 1 Gyr, only stars with masses < 2 M¯ are still on the main sequence) •Most of the light is emitted while stars are on the giant branch •The sta ...
Coma Cluster of Galaxies Activity
... of the visible universe 13 billion light years away. Nobody knows for sure, but it is estimated that there are 100 billion galaxies or more in the visible universe, and many more beyond that. Galaxies live in a variety of environments. Sometimes large numbers of them are packed close together in clu ...
... of the visible universe 13 billion light years away. Nobody knows for sure, but it is estimated that there are 100 billion galaxies or more in the visible universe, and many more beyond that. Galaxies live in a variety of environments. Sometimes large numbers of them are packed close together in clu ...
Extragalactic Astrophysics 1 AA 2011-2012 Prof. LA Antonelli
... absolute value, but relative velocity has a transverse component as in figure this configuration of proper motions was already noted around 1900 and explained by Oort in 1927 with the differential rotation ...
... absolute value, but relative velocity has a transverse component as in figure this configuration of proper motions was already noted around 1900 and explained by Oort in 1927 with the differential rotation ...
Galactic Evolution:
... and object is still lacking. There are attempts to construct some comprehensive and software package for study of the galactic evolution. I just mention th Galaxy Evolution tool (GEtool) that is a software package currently being developed to selfconsistently model of chemical and spectral evolution ...
... and object is still lacking. There are attempts to construct some comprehensive and software package for study of the galactic evolution. I just mention th Galaxy Evolution tool (GEtool) that is a software package currently being developed to selfconsistently model of chemical and spectral evolution ...
The cosmic distance scale
... Use the relation you found in one of the preparatory exercises and the min/max magnitudes of each Cepheid to calculate the observed mean magnitudes. These have to be corrected for interstellar extinction. The light traveling to us from M100 is not just passing through the vacuum of space, some of it ...
... Use the relation you found in one of the preparatory exercises and the min/max magnitudes of each Cepheid to calculate the observed mean magnitudes. These have to be corrected for interstellar extinction. The light traveling to us from M100 is not just passing through the vacuum of space, some of it ...
The cosmic distance scale
... W20 needs to be corrected for 2 effects. The first one is that HI does not follow perfectly circular orbits, but has some random motion, whose effect is to broaden the observed lines. This can be estimated to be typically 10 km/s. The second effect is due to the inclination. The width that we measur ...
... W20 needs to be corrected for 2 effects. The first one is that HI does not follow perfectly circular orbits, but has some random motion, whose effect is to broaden the observed lines. This can be estimated to be typically 10 km/s. The second effect is due to the inclination. The width that we measur ...
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.