Luis Kaim Gebara

Parts of rural Alaska have been experiencing unseasonable warmth this winter. Months of higher-than-normal temperatures have opened dangerous gaps in frozen rivers that residents use for travel since there are no roads. One particularly troublesome ice highway is the Kuskokwim River, where a family of six traveling on a snowmobile and sled plunged into a hole on New Year's Eve. One man died, and the others survived.

NASA has bumped an astronaut off an upcoming spaceflight, a rare move for the space agency. Astronaut Jeanette Epps was supposed to blast off on a Russian rocket in June, and would have been the first African-American astronaut to live on the International Space Station. Late Thursday, NASA announced it was pulling Epps off the mission but didn't disclose why. Another astronaut will take her place. In this Sept.

The first steps that could one day make smoking an obsolete habit get underway next week. U.S. regulators will hold a public meeting about a device that heats a Marlboro-branded tobacco, but doesn't burn it. It's part of a delicate plan that would drastically cut nicotine levels in cigarettes and allow lower-risk products for those who can't or won't quit. It's a thorny proposition because it offers a role for the tobacco industry in the effort to eliminate the diseases caused by smoking.