Today, scientists are fascinated by many things in the outer space and the universe. With constant discoveries of new planets and new moons the discoveries of evidence of life on other planets and galaxies, the work of astronomers is truly interesting. Today, scientists are looking for answers to one of the undying questions: is our universe expanding?
From the time that Einstein constructed his theory of general relativity and was applied to the universe, there have been suspicions that our universe was expanding. In the 1920s, when Milton Humason and Edwin Hubble discovered that practically all the galaxies that were in the sky were actually moving away from us and our galaxy at great speeds, scientists started considering that the universe could be expanding at a fast rate. However it was not until the year 2000 at the turn of the millennium that some key evidence were found to support the expansion of the universe. These key pieces of evidence were in the form of extensive redshift surveys that were done of very distant objects.
Our expanding universe is usually referred to as the most significant discovery in modern cosmology. Back in Einstein’s time, the predominant theory was his steady-state theory that stated the universe remained to be the same size and balanced. Einstein’s equations back then predicted universal contraction or expansion but not stasis. With his equations, he artificially introduced some kind of a stabilizing variable into them, which he referred to as the “cosmological constant.” Once he found out about the observations of Hubble that supported the theory of the expansion of the universe, he called his findings his “greatest blunder.”
The phenomenon which first led astronomers and cosmologists to predict that the universe was indeed expanding was the analysis of redshift by Hubble. Through using the Mount Wilson Observatory, the best telescope during that time, Hubble was able to view the distant galaxies and saw that they appeared to be progressively redder. He then looked further away into space, and through extension as well as further back in time, as light takes several billions of years to travel to Earth; and because the redness factor was able to correlate so well with the increases in the distances, Hubble has reason to believe that the expansion of the universe was a reliable phenomenon that has a physical cause. The cause that he established was this: as the universe continues to expand, the underlying space increases its volume, but the light which is traveling through it stays the same. This expanding space stretches out the light’s wavelength, making it longer and consequently, more red.
In 1998, there was a discovery made which proved that the universe is not only expanding, but is also expanding at a rate which continues to accelerate. Aside from this cosmological and astronomical discovery, there have been a lot of other scientific discoveries made in outer space and the universe. Some information has even been gathered by missions to space and space shuttles. If you would like to know more about our universe and other heavenly bodies, you can always look for information online. Aside from useful information, you would also be able to do some internet shopping for all kinds of items such as designer sunglasses like Marc Jacobs sunglasses.