confirmed martian rocks on earth. millions of years ago something smashed into mars sending fragments hurling into space, and occasionally some of them fall to earth. and a new warning now for people who rely way too much on their headphones. a new study finds pedestrians who are regularly plugged into electronics are now three times more likely to die. trace gallagher live in los angeles. trace? >> reporter: you know, megyn, it was an emergency room doctor from the university of maryland medical center who decided to conduct this study after a local teenager was killed by a train. the teen was wearing headphones and never made any attempt to get out of the way of the train even though the train's horn was sounding. so the doctor gathered some other researchers, they went back and looked between 2004 and 2011, and they found 116 different incidents of people who were hit by trains and other vehicles while wearing headphones. 116.