Changes

The USA is not the only country to lack a legal definition of outer space; however, one common definition in countries which use the [[metric system]] is the Kármán line, which labels "space" as anything about 62.1 miles in altitude.<ref>http://books.google.com/books?id=NR7mFXCB-wgC&pg=PA239&lpg=PA239&dq=legal+boundary+of+space&source=web&ots=Q56qiINocX&sig=bP5Ye5YBYytJpikkfp-lUznLJUk&hl=en</ref><ref>http://www.fai.org/press_releases/2004/documents/12-04_100km_astronautics.doc</ref>

The USA is not the only country to lack a legal definition of outer space; however, one common definition in countries which use the [[metric system]] is the Kármán line, which labels "space" as anything about 62.1 miles in altitude.<ref>http://books.google.com/books?id=NR7mFXCB-wgC&pg=PA239&lpg=PA239&dq=legal+boundary+of+space&source=web&ots=Q56qiINocX&sig=bP5Ye5YBYytJpikkfp-lUznLJUk&hl=en</ref><ref>http://www.fai.org/press_releases/2004/documents/12-04_100km_astronautics.doc</ref>

Signatories of the so-called Outer Space Treaty have agreed not to test nuclear weapons in space, or claim land in outer space as sovereign territory. <ref>http://www.unoosa.org/oosa/SpaceLaw/outerspt.html</ref>

Signatories of the so-called Outer Space Treaty have agreed not to test nuclear weapons in space, or claim land in outer space as sovereign territory.<ref>http://www.unoosa.org/oosa/SpaceLaw/outerspt.html</ref>

==Greek philosophy==

==Greek philosophy==

The [[Ancient Greece|ancient Greek]]s debated whether space was finite or infinite. The ancient Greeks recognized that it was difficult to imagine what an infinite universe might look like. But they also wondered that if the universe were finite, and you stuck out your hand at the edge, where would your hand go? The Greeks' two problems with the universe represented a [[paradox]] - the universe had to be either finite or infinite, and both alternatives presented problems. <ref>[http://skyserver.sdss.org/dr1/en/astro/universe/universe.asp The Expanding Universe], Sloan Sky Survey </ref>

The [[Ancient Greece|ancient Greek]]s debated whether space was finite or infinite. The ancient Greeks recognized that it was difficult to imagine what an infinite universe might look like. But they also wondered that if the universe were finite, and you stuck out your hand at the edge, where would your hand go? The Greeks' two problems with the universe represented a [[paradox]] - the universe had to be either finite or infinite, and both alternatives presented problems.<ref>[http://skyserver.sdss.org/dr1/en/astro/universe/universe.asp The Expanding Universe], Sloan Sky Survey</ref>

==Notes==

==Notes==