Galaxies are rotating collections of stars, dust, gas, and debris;galaxies may also contain stellar objects such as neutron stars. Galaxies are held together by their own gravity. The galaxy that the Earth is apart of is the Milky Way, a galaxy in a cluster of galaxies referred to as the Local Group.
There are two theories as to how galaxies are formed. One theory claims that after vast dust clouds collapse under their own gravitational pull, the conditions are right and star formation begins. The other theory states that when the universe was newly created that the small "pods" of matter clumped together. The Hubble Telescope has taken photographs of these "pods", providing some evidence for this theory.
It is also thought that early galaxies were spiral galaxies, and later merged to form elliptical galaxies. Whenever a larger galaxy collided with a smaller galaxy the larger galaxy will absorb the smaller one, resulting in an even bigger galaxy.
There are two theories as to how galaxies are formed. One theory claims that after vast dust clouds collapse under their own gravitational pull, the conditions are right and star formation begins. The other theory states that when the universe was newly created that the small "pods" of matter clumped together. The Hubble Telescope has taken photographs of these "pods", providing some evidence for this theory.
It is also thought that early galaxies were spiral galaxies, and later merged to form elliptical galaxies. Whenever a larger galaxy collided with a smaller galaxy the larger galaxy will absorb the smaller one, resulting in an even bigger galaxy.
1) What are galaxies?
3) What galaxy is the Earth apart of?
4) What cluster of galaxies is the Milky Way apart of?
5) What are "pods"?
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