In this issue:
"The Ultimate Social Network": Researchers are trying to sort out who is in charge - the friendly microbes that live inside all of us or people.
"Super Supernovae": The largest stars die in explosions more powerful than anyone previously thought possible.
"The Human Brain Project": A digital construction of the human brain could transform neuroscience and medicine and reveal new ways of making more powerful computers.
"Fusion's Missing Pieces": The world's most complex science experiment has encountered a few potholes.
©2012 Scientific American