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New study: Sea level rise accelerating

Global sea level rise has been accelerating in recent decades, rather than increasing steadily, according to a new study based on 25 years of NASA and European satellite data.

When can you see Earth’s shadow?

Like all worlds orbiting suns, our planet Earth casts a shadow. Here are some times to look for it.

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.

Great Backyard Bird Count February 16–19

Scientists need your help counting birds for the 21st annual Great Backyard Bird Count. It is free and easy to participate. Find out how here.

What is radiocarbon dating?

At a very steady rate, unstable carbon-14 gradually decays to carbon-12. The ratio of these carbon isotopes reveals the ages of some of Earth’s oldest inhabitants.

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.

Humans witnessed fire-covered Earth at end of Ice Age

New research suggests that some 12,800 years ago, an astonishing 10 percent of the Earth’s land surface was consumed by fires, thanks to a cosmic impact.

Volcán de Fuego from Earth and space

Volcán de Fuego – literally “fire volcano” – is one of Central America’s most active volcanos. Photos of its recent eruption here.

Scientists solve a methane puzzle

Since 2006, levels of heat-trapping methane in Earth’s atmosphere have risen sharply. A new study settles a disagreement about the source.

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.

Tides, and the pull of the moon and sun

Expect higher-than-usual tides in the days following the January 31, 2018, full supermoon.

These clouds are called ship tracks

Ship tracks typically form among low-lying stratus and cumulus clouds. They form around exhaust particles released by ships.

Swollen Seine causing Paris floods

Eastern France experienced unusually heavy rainfall throughout January 2018, and last week the Seine, in Paris, began a precipitous rise. Videos here.

Ingredients for life in space rocks that fell to Earth

Two rocks that crashed to Earth from space in 1998 are the 1st meteorites found to contain both liquid water and a mix of complex organic compounds such as hydrocarbons and amino acids.

Analysis reveals tiny dino with rainbow feathers

This bird-like dinosaur lived in China about 161 million years ago. Scientists think it might have used its rainbow ruff to dazzle potential mates.

Tsunami warnings issued – later canceled – after powerful Alaska quake

A powerful earthquake struck 174 miles (280 km) southeast of Kodiak, Alaska, early on January 23. Tsunami watches or warnings were issued – later canceled – for western North America and Hawaii.

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.

NASA and NOAA: 2017 was record-setting for warmth

NASA says 2nd-warmest year on record. NOAA says 3rd-warmest. Their methodologies differ slightly, but – by both standards – the 2017 results make the past 4 years the hottest yet recorded.

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?