Science

How the Challenger disaster changed space exploration

By Geoff Bennett

It’s been 40 years since the space shuttle Challenger exploded just after takeoff. Geoff Bennett speaks with science correspondent Miles O’Brien, who covered the aftermath of the disaster, about how it affected the U.S. space program.

Leader in smallpox eradication, Dr. William Foege, dies at 89

By Mike Stobbe, Associated Press

Dr. William Foege, a leader of one of humanity's greatest public health victories — the global eradication of smallpox — has died.

The last refuge for a tiny hummingbird facing extinction is an ancient forest in Ecuador

By Gonzalo Solano, Cesar Olmos, Associated Press

Deep in the Ecuadorian Andes, the Yanacocha Reserve is the last refuge for a tiny hummingbird teetering on the edge of extinction.

These rock salt alternatives for clearing ice and snow are safer for your pets and yards

By Alexa St. John, Caleigh Wells, Associated Press

It's easy to dash to the closest hardware store to grab a bag of salt, but experts say there are a lot of environmental and other factors to consider when tackling all that ice and snow.

Thousands of flights canceled as massive winter storm bears down across the U.S.

By Jeff Amy, Dave Collins, Thomas Peipert, Associated Press

Thousands of flights across the U.S. set to take off over the weekend were canceled as a monster storm started to wreak havoc Saturday across much of the country, knocking out power and snarling major roadways with dangerous ice.

Why Earth's melting glaciers matter more than we think

By William Brangham

Ice in the Arctic and Antarctica plays a critical role in maintaining life on Earth, and it is melting faster than previously thought. This is threatening our planet with potentially massive sea-level rise, weather disruptions and further global warming. Horizons…

Why Earth's melting glaciers matter more than we think

By William Brangham, Claire Mufson, Madison Staten, Satvi Sunkara, Juliet Fuisz, Alexa Gold, Zoie Lambert

WATCH: Returned astronauts say ultrasound machine 'really helped' during medical crisis

By Marcia Dunn, Associated Press

During their first public appearance since returning to Earth, the four astronauts refused Wednesday to say which one of them needed medical attention and for what reason. It was NASA's first medical evacuation in 65 years of human spaceflight.

Stretched polar vortex, moisture and a lack of sea ice all to blame for dangerous winter blast, meteorologists say

By Seth Borenstein, Associated Press

Meteorologists said the eastern two-thirds of the nation is threatened with a winter storm that could rival the damage of a major hurricane and has some origins in an Arctic that is warming from climate change.