Expanding universe, Science

The Expanding Universe:

Hubble's observations had proved  the existence of  galaxies. After mapping as many galaxies as could be seen by  the telescopes then'available, he turned his attention to the motion of  galaxies. He was motivated to do this by a puzzling report of  V.M.  Slipher, an American astronomer.  He  had  discovered  in 1912 that many of  the faint nebulae were moving away from the Earth at very great speeds. Their spectral lines exhibited large shifts towards the red end (what is called as red shift). This seemed peculiar because stars in  the Milky Way Galaxy move at much smaller speeds, some moving away from us with others moving towards us. Slipher had made these observations a decade before galaxies were discovered. Then it was thought that the nebulae were objects in our own galaxy. He did not know what  to make of  his observations. But as Hubble knew that these nebulae were galaxies, he began a systematic study of the relation between their speeds and their distances alongwith his colleague M.L. Humason. What they found was very interesting. To put  it  simply, his observations showed that; i)  all galaxies were moving away from us; ii)  the farther away a galaxy was from our Galaxy, the greater was the speed at which it moved away. Hubble's discovery put forth the picture of  an expanding universe. But if  all the galaxies are moving away from us, are we at the centre of  the Universe? No.  If  we were situated in another galaxy, even then the other galaxies would seem to move away from us. You can understand this picture of  an expanding universe if  you study Fig and also perform a simple activity. 

488_Expanding Universe.png

Posted Date: 9/28/2012 1:45:55 AM | Location : United States







Related Discussions:- Expanding universe, Assignment Help, Ask Question on Expanding universe, Get Answer, Expert's Help, Expanding universe Discussions

Write discussion on Expanding universe
Your posts are moderated
Related Questions
Define age related changes in Excretory System There is a progressive decrease in the number and size of nephrons fiasic unit of the kidney). There is a 10% decrease in renal p

The digestive system is made up of two groups of organs: Alimentary  tract, which  includes mouth, pharynx,  oesophagys,  stomach, small intestine,  large intestine, appendix

Explain Immune System The animals and the human beings are forced to encounter many dangerous microbe in their day-to-day life, through water, air and food. Inside our body the

how i can get the nams of all the body of the human

Explain Macrophages They are large, long living effective phagocytes, which enlarge out of monocytes. It is an irregular cell about 25-50 mm in size. It has a large ovoid nucle

Explain in detail about the Sedimentary rocks  Sedimentary rocks are formed from the breakdown of  igneous rocks.  These rocks are broken apart by plant roots, ice wedges, and

Studying broken rocks with a magnifying glass Study freshly broken rocks with a magnifying glass and try to find crystals of dissimilar minerals. The crystals of dissimilar mi

Ship-building: The shipbuilding industry in  the seventeenth century. witnessed far-reaching changes that mainly resulted from imitating European techniques. The Indian sea-g

Explain the Duodenum The first part of the small intestine is called the diodenum. It is about 10 inches in length. At the mid-point of the duodenum, there is a common opening

what are the reactions taking place during alcoholic acidity estimation for wheat flour