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MightyMeanie
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How does other galaxies differ from out own?
With the caveat that there is still a little debate about it, using doppler shift to find distance (there are other ways for closer galaxies) and measuring the angular size will give the actual size.misskitty said:Is there a way to measure how big or small a galaxy is compared to ours?
It is estimated that there are approximately 2 trillion galaxies in the observable universe. However, this number is constantly growing as our technology and understanding of the universe improves.
Spiral galaxies have a flat disk shape with arms that spiral out from the center. Elliptical galaxies are round or oval in shape and have less defined structure. Irregular galaxies have no particular shape or structure, often due to interactions with other galaxies.
The sizes of galaxies can vary greatly, with the smallest being only a few hundred light years in diameter and the largest stretching over hundreds of thousands of light years. The size of a galaxy is typically determined by the amount of matter it contains and how it is distributed.
The ages of galaxies also vary, with some being as old as 13 billion years (about the age of the universe) and others being much younger. The age of a galaxy is often determined by studying the stars within it and their chemical composition.
The color of a galaxy is determined by the type and amount of stars within it. For example, younger galaxies with many hot, bright, blue stars will appear blue in color, while older galaxies with cooler, redder stars will appear red. The color can also be affected by the presence of dust and gas within the galaxy.