Galaxy part 4

Magellan Cloud

1. Galaxy Irregular

A few percent of galaxies are very bright in the sky is classified as irregular galaxies. Type of irregular galaxy is divided into two groups: the so-called group I and group IRR IRR II. IRR Group I consists of classes O and B stars and bright nebulae. Examples of this first group of the IRR is Large Magellanic Cloud and Small Magellanic Cloud, a neighboring galaxy closest to us. This type of galaxy contains many star clusters, variable stars, maharaksasa, and nebula gas. These galaxies consist of old stars and young stars.

Galaxy II still resembles IRR IRR I, but did not reveal the existence of a star or star cluster that can be clearly separated from this galaxy that remain reveal the composition of an amorphous (amorphous). This marks the stars in this galaxy is not bright enough to be observed separately own. Besides the three types of galaxies that have been described, there are several other types such as type of CD, N, and S.



2. Radio Galaxy



The discovery of cosmic radio waves in 1931 showed that a continuous radio energy is emitted from the disk and halo of our galaxy. Since World War II have been found thousands of radio sources deskrit that each occupies a very small region in the sky. The vast majority of sources is known as ekstragalaktika deskrit.

The first identification of radio sources with ekstragalaktik object is made in the year 1951. One of the strongest radio sources in space was found in 1948, called Cygnus A in the constellation Cygnus. Although all the galaxies emit radio waves, most of them are normal, just like the Milky Way galaxy, which emits radio waves with continuous spectrum emitted from the disk and halo, and the amount of radiation between 1033 until 1034 reratanya Js, very small when compared to visible wave energy generated . Besides, in many galaxies have been observed the existence of neutral hydrogen line. Doppler shift of the emission line, indicating the same radial velocity for a galaxy, just as the shift of spectral lines kasatmatanya.

Instead there are galaxies that emit radio waves exceptional in very large quantities around 1037 Js, an amount of energy equal to or greater than the luminosity optisnya, so dinakan radio galaxies. Radio galaxies in all aspects of visual resemble normal galaxies, but others have a unique cirri, which is linked to its radio luminosity is extraordinary. For example, the galaxy NGC 1068, emit radio energy 100 times the ordinary spiral galaxy. Similarly, M87, a giant galaxy in the constellation Virgo eleptik emit radio energy thousands of times more of these types of galaxies are the brightest.

Cen A galaxy with radio track

Some types of radio galaxies are quite complex as the source Cygnus A that although the distance is 1 billion light years, but has the strongest radio sources observed. Power emitted by the source Cygnus A on the radio frequency of about 1038 J / s, far more than the visible light produced by the visible galaxy. It turns out some very strong sources of radio galaxies to determine its amazing, like having the power up to 1040 J / s or about 100 trillion times the luminosity of the sun. This is a very compressed object, and have a very strong magnetic field. All this indicates that this object is a powerful source of energy that clog small. It is estimated that energy comes from a thousand million times the mass of solar masses.