In the cover story, we'll learn about the illusion of gravity, nature's most baffling force. Then, we'll take a look at what must be done to prepare for a possible flu pandemic. Also, did life come from another world? New studies hint that microorganisms hitching onto meteorites could have survived an interplanetary journey. Finally, we'll take at look at how the brain's activity gives rise to a constant sense of being oneself.
©2005 Scientific American