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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.

What is the edge of the universe like? Is it a brick wall or what? Will we be able to go past our universe someday?

Too bad it's not a brick wall or something like that. Actually, there really is no "edge" of the universe so we can't go past it.

Scientists don't know what will happen to the universe. One possibility is that the universe will expand forever. This means that the universe is infinite in size so it doesn't have an edge. It just goes on and on and on.

The second possibility is that the universe will end in a Big Crunch. In this case the universe is finite in size because of gravity.

So if it's finite in size, why isn't there an edge we can go to? That's because of a weird little thing gravity does to space--it curves it!

Einstein first came up with the idea of gravity curving space. That's how the Earth orbits the sun. It wants to go straight but the Sun curves the space around it so the Earth can't go flying off.

There is so much matter that space is bent back on itself! It's sort of like how you can bend a wire so much that its ends will touch. You bent the wire back on itself and came up with a circle. When you walk around a true circle you can go forever without coming to an edge. That's the same with the universe.

Submitted by Lance (Utah, USA)
Submitted by Brent (Tenessee, USA)
Submitted by Alyssa (California, USA)
(August 21, 1997)



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Learn about Earth and space science, and have fun while doing it! The games section of our online store includes a climate change card game and the Traveling Nitrogen game!

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF