SPACE SHUTTLE COLUMBIA MOURNING: This is an excerpt from the NASA Columbia Condolences book:

"The greatest heroes are those who ride the leading edge of technology, often at great peril, to pave the way for the advancement of humanity. The crew of STS-107 are among the greatest of heroes. May their sacrifice be transformed into a beacon of hope for all -- that we may continue to learn from our mistakes and carry on our mission of discovery. And even beyond discovery, these heroes served an even greater goal - the unity of humankind. For it has been said that, from space, one can see no political borders -- from that vantage, we are not residents of any one country, rather, we are residents of Planet Earth. Your family members, as discoverers and uniters, are indeed the greatest of heroes. They will be missed."