Stricter truck pollution rule would prevent 500 deaths a year in Chicago region, study shows
It would require that manufacturers of medium and heavy-duty trucks slowly ramp up the number of zero-emissions vehicles sold.
NASA's stuck astronauts finally on their way back to Earth after 9 months in space
Butch Wilmore and Suni Williams left the International Space Station in a SpaceX capsule early Tuesday, checking out with the cosmonaut and astronaut.