“If the expansion of the space of the universe is uniform in all directions, an observer located in anyone of the galaxies will see all other galaxies running away from him at velocities proportional to their distances from the observer.” -George Gamow
When Einstein put forth his space-and-time changing theory of General Relativity, one of the consequences he didn’t anticipate — and, in fact, resisted — was the fact that a static Universe would be unstable, and that the Universe must be either expanding or contracting. While the theoretical work of many, such as de Sitter, Friedmann and Lemaître, pointed towards this conclusion, it was the observational work of Hubble in the 1920s that sealed the deal.
Image credit: ESO and Digitized Sky Survey 2. Acknowledgment: Davide De Martin.
By observing the distances and recessional velocities of a great many galaxies, he was able to not only show that the Universe was expanding, but he measured the expansion rate. Yet not every galaxy is as favorably situated as our own; while we have hundreds of thousands of galaxies within a few hundred million light years, some galaxies have none. In fact, if we were situated at the same location as MCG+01-02-015, we wouldn’t have discovered a single galaxy beyond our own until the 1960s.
Image credit: ESA/Hubble & NASA and N. Gorin (STScI); Acknowledgement: Judy Schmidt.
Would we have given up, and failed to discover not only the expanding Universe, but the Big Bang and dark matter as well? Find out about this unusual void galaxy, and be thankful for our abundant location in the Universe!
from ScienceBlogs http://ift.tt/1mizQrz
“If the expansion of the space of the universe is uniform in all directions, an observer located in anyone of the galaxies will see all other galaxies running away from him at velocities proportional to their distances from the observer.” -George Gamow
When Einstein put forth his space-and-time changing theory of General Relativity, one of the consequences he didn’t anticipate — and, in fact, resisted — was the fact that a static Universe would be unstable, and that the Universe must be either expanding or contracting. While the theoretical work of many, such as de Sitter, Friedmann and Lemaître, pointed towards this conclusion, it was the observational work of Hubble in the 1920s that sealed the deal.
Image credit: ESO and Digitized Sky Survey 2. Acknowledgment: Davide De Martin.
By observing the distances and recessional velocities of a great many galaxies, he was able to not only show that the Universe was expanding, but he measured the expansion rate. Yet not every galaxy is as favorably situated as our own; while we have hundreds of thousands of galaxies within a few hundred million light years, some galaxies have none. In fact, if we were situated at the same location as MCG+01-02-015, we wouldn’t have discovered a single galaxy beyond our own until the 1960s.
Image credit: ESA/Hubble & NASA and N. Gorin (STScI); Acknowledgement: Judy Schmidt.
Would we have given up, and failed to discover not only the expanding Universe, but the Big Bang and dark matter as well? Find out about this unusual void galaxy, and be thankful for our abundant location in the Universe!
from ScienceBlogs http://ift.tt/1mizQrz
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