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Future cities built with volcanic ash?

After water, concrete is the world’s most-used building material. MIT researchers worked with volcanic ash as a concrete additive and substantially reduced building costs.

Day Zero approaches as Cape Town’s water runs out

Cape Town – the South African city of 3.7 million people – is on the verge of running out of water. Day Zero is the day the taps will get turned off.

View of Winter Olympics from space

Ready for the Olympics? Here’s a look at the sites of the 2018 Winter Games, the South Korean cities of Pyeongchang and Gangneung, from above.

Harvard study links breast cancer to light at night

Artificial light has transformed the night sky, a change researchers continue to link to health problems.

Why no full moon in February 2018?

January and March 2018 have 2 full moons. February has none. Astronomer David Chapman explains moon cycles and calendars, with a word about moon names in the indigenous Mi’kmaw nation of Canada’s northern woodlands.

Is a major California earthquake overdue?

According to current forecasts, California has a 93% chance of an earthquake of magnitude 7 or greater occurring by 2045.

Scientists find oldest modern human fossil outside Africa

This fossil suggests Homo sapiens left Africa 50,000 years earlier than previously thought.

January 31 lunar eclipse: What scientists can learn

The lunar eclipse January 31 offers scientists a chance to see what happens when the surface of the moon cools quickly.

50 years ago: Thule incident

On January 21, 1968, in what came to be known as the Thule incident, a U.S. jet carrying 4 nuclear bombs crashed in Greenland, spreading radioactive wreckage across 3 square miles of a frozen fjord.

Why did passenger pigeons die out?

In the 19th century, passenger pigeons were so numerous that hunters competed to shoot as many as possible. But the last passenger pigeon died in the Cincinnati Zoo over 100 years ago. How did it all go so wrong?