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The scale of the universe: http://htwins.net/scale2/ http://htwins.net/scale2/

• joering2 15y ago
  wow this was amazing!! thanks for sharing!! everyone with kids aboard should watch it!!
• iwwr 15y ago
  The estimated size of the universe beyond the visible part is at most a guess. It could be infinite. This would mean that even at the time of the big bang there was a lot of volume, just very high energy density. What we do know is that the part universe we live in has an event horizon. We can see distant objects as they looked in the past. The distance to those objects may be as much as 40-50bn light years now, due to the expansion of space. And if we ventured to travel, even at the speed of light, there are sections of the universe visible now that will fall out of view, and we therefore never reach. If the universe is accelerating, the region of possible travel will shrink. So we have a so-called "visible universe", a region we can observe or directly infer the effects of. Then there is the "accessible universe", the region we could travel in at the speed of light. All this embedded in a presumably larger, but inaccessible universe.