Beyond the milky way galaxy, Science

Beyond  the milky Way Galaxy:

Let us now move away from the Earth and venture into the space beyond. If we were at a point far out in space we would see scattered in space, a  large number of  faint, wispy tendrils of  light. These are all galaxies. As we have said earlier in Sec.  these galaxies are made up of billions of  stars, and clouds of gas and dust. The universe is full of galaxies. Some of them are  soliky wanderers. Most ofthem movein clust&s. drifting endlessly in the great cosmic dark. Shapes of  galaxies The galaxies are usually found in three shapes: spiral galaxies, elliptical galaxies and irregular galaxies (see Fig. 9.9). Further refinements have been suggested  in recent years, but we will not go into those details. The elliptical galaxies  are so  called because they have an elliptical  shape on a photographic plate. Elliptical galaxies in general do not have much gas or dust from which to form new stars, and they consist of old stars. The irregular galaxies do not show any coherent structure. 'he number of elliptical and spiral galaxies is almost equal, whereas the irregular ones comprise about  10%  of all salaxies.  

2315_Beyond  the milky Way Galaxy.png

Before going  too deep into the space, let's take a closer look at, what astronomers on' Earth like to call, the Local Group of Galaxies. Its cross-section is several million light years, it is made up of  around twenty galaxies. The nearest galaxies  to the Milky Way Galaxy are the Large and Small Magellanic Clouds, visible in the Southern hemisphere. They are irregular in shape. The galaxy Andromeda'lies nearly two million light years away and is visible to the unaided eye. It is a spiral galaxy, three times bigger and brighter than ours. As we move further out, we find that such groupings, or clusters of  galaxies, are extremely common. There are some hundreds of billions of  galaxies in the universe which form clusters of all kinds. There are rich clusters containing as many as ten thousand galaxies and poor clusters having only a few galaxies. Our own galaxy is a member of  a poor cluster. The nearest rich cluster, at a distance of about 70 million light years, is Virgo. It is irregular in shape and is huge, extending 7 million light years from end to end. Like galaxies, clusters are also shaped like spirals, ellipses or they may be irregular. In recent years, one more step has been added in understanding this physical structure of  the universe. There is evidence to suggest that the clusters of  galaxies, rich and poor, in turn form superclusters or supergalaxies  (i.e. clusters of clusters) that are 200-300 million light years in diameter. They may be made up of about a 100 member clusters. The clusters, Local Group and Virgo, are members of  the same supercluster. The superclusters are very much alike. They are rather evenly distributed in space. Thus, on a larger scale than this, the universe appears uniform, that is,  it  has the same structure and composition everywhere, it looks the same in all directions.  

Posted Date: 9/28/2012 1:25:59 AM | Location : United States







Related Discussions:- Beyond the milky way galaxy, Assignment Help, Ask Question on Beyond the milky way galaxy, Get Answer, Expert's Help, Beyond the milky way galaxy Discussions

Write discussion on Beyond the milky way galaxy
Your posts are moderated
Related Questions
The effect of petrol on surface tension Being sure that the plate is has to be clean. It is wise to rinse the plate in cold water for a time before filling it. Instead of soap,

What is a chemical compound? By definition, a compound is a substance in which two or more different elements have combined. There are millions of examples of compounds all aro

Cosmic Distances: If  we asked you what the distance between Delhi and Kanyakumari is, you would say that it  is roughly 3000 km. Another way of answering the question would

Explain an Amniocentesis An amniocentesis is a process used to obtain a small sample of the amniotic fluid which surrounds the foetus to diagnose chromosomal disorders and open

Explain the Conditions for Ventricular Fibrillation Ventricular fibrillation may be seen in the following two conditions: 1) When a person is electrocuted, and 2)  As a c

Define Growth Hormone (GH) It is a protein containing 19lamino acids in a single chain. It is secreted by somatotrophs throughout life even though growth stops at adolescence.

What is your evaluation of the effectiveness of the U.S. health care system in the context of delivery, finance, management, and/or sustainability? What are the issues that prompte

Emergence of Science: We gave you a glimpse of  the social structure in  India during the Iron Age. With the emergence of ordered urban societies, the stage was set for a tre


Question 1. Explain Sialography? How will you perform the same? 2. How will you set up your radiology department to take up the IVU studies? 3. Discuss how fluoroscopy di