What could be the largest structure yet seen in the observable universe has emerged from data taken during a 12-year survey of the night sky.
The discovery is an apparent cluster of quasars some 4 billion light-years across. If it holds up to further scrutiny, it could challenge a long-held assumption that at the cosmos's largest scales, the physical processes at work and the distribution of matter and energy are the same, regardless of an observer's location.




A new report warns that climate change driven by human activity already is affecting the American people and economy, with more frequent and intense heat waves, heavy downpours and, in some places, floods and droughts.
Robert F. Kennedy Jr. is convinced that a lone gunman wasn't solely responsible for the assassination of his uncle, President John F. Kennedy, and said his father believed the Warren Commission report was a "shoddy piece of workmanship."
Future generations of Americans can expect to spend 25 days a year sweltering in temperatures above 100F (38C), with climate change on course to turn the country into a hotter, drier, and more disaster-prone place.
A persistent drought held its grip on America's bread basket on Thursday, with no sign of relief for the four main wheat-growing states.





























