How Big is the Universe?
Jun 5, 2019 12:32:11 GMT -5
Post by Radrook Admin on Jun 5, 2019 12:32:11 GMT -5
How Big is the Universe?
When measuring distances on Earth and in our solar system, we use kilometers or miles. But since the universe is so large, and other stars so far away, distances are measured in light years, that is the distance that light traveling at 186,000 miles per second, covers in one year. The nearest star is approx four light years away. But the farthest we can see is approx 13 billion light years in any direction. However, that doesn't mean that there is nothing beyond that distance. You see, the universe was set into motion at the time it emerged from seemingly nowhere in the event called the Big Bang and has been constantly expanding ever since.
But the expansion hasn't been at a steady rate. It was discovered that the farther away we look, the faster the universe seems to be expanding. Based on that increasing rate, it has been calculated to be expanding faster than the speed of light. The effect of such an expansion is that it has created two two universes, the detectable universe and the undetectable universe.
The detectable universe is the universe we can detect via opitcal and radio telescopes. The undetectable part is the region from which light will never reach us. So the figures provided for the size of the universe are for the detectable universe only or how large the detectable univer WAS at the time that the light from the objects began its journey towards our direction. That journey is estimated to have been approx 13 billion light years ago. In other words, no matter in what direction we look, the farthest we can see is 13 billion light years.
Which gives us a diameter to the visible universe at that time of approx 26 billion light years thirteen billion years ago. What its diameter is right now is impossible to calculate. Some have estimated that the part we can see might be like like a golf ball cos ago.mpared to the planet Pluto to the part we can't. This is understandable since the universe we are detecting now has hat approx 13 billion years to expand since that light left its source. You can do a lot of expanding in thirteen billion years.
BTW
To creatures living in the undetectable parts, we are undetectable and seem to be dtstancing ourselves at faster than the speed of light.