Hobbies And Interests
Size
The Milky Way galaxy alone is estimated to measure 1,000 light years from side to side. If the Milky Way were an ocean, the Earth would not even be as large as a drop of water. But how large is the universe? This we do not know, because we only can estimate the size of the observable universe, which has a diameter 280 billion light years across. Beyond that is a mystery, especially as light can't travel fast enough to go past the observable universe and give us a picture.
Considerations
Galaxies rotate, although they do it very slowly. Since galaxies rotate, the theory is the entire universe also rotates. The Milky Way galaxy looks like a spiral with two major arms. The Earth is located in a minor arm (Orion) that connects to a major arm (Perseus). The universe never really stays still. Also, it's now thought that other dimensions intersect with our 3-dimensional universe. So determining the size of the universe, to figure out where in it the Earth falls, is next to impossible to do.
Theories/Speculation
Another theory is that the universe is growing, and will at some point--billions and billions of years into the future--collapse into one giant black hole. The gist is that Earth and the Milky Way keep shifting positions in the universe as the universe itself changes.
Significance
Throughout history, many religious doctrines taught that the Earth was the center of the universe--which would explain why God bothers so much with it. As it becomes ever clearer that we cannot find the center of the universe, let alone our place in it, our importance as the pinnacle of creation dwindles.
Expert Insight
There has been an attempt by leading scientists at Princeton to make a 2-dimensional map of the universe, in which one end of the universe is where the Big Bang began and the other is the surface of the Earth. According to this map, the Milky Way galaxy is to the far right of the universe (see Resources). Also according to the map, the center of the universe is a galaxy known only as PSR-P1620-24.