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Auroras over the South Pole

A strong G3-class geomagnetic storm sparked auroras over both poles of Earth this past weekend. Hunter Davis, at the South Pole, captured images.

Clouds that look like ocean waves

They’re called Kelvin Helmholzt clouds, aka billow clouds or shear-gravity clouds, and they look like breaking ocean waves.

Tides, and the pull of the moon and sun

Expect higher-than-usual tides for a few days following the May 25, 2017 new supermoon.

Top 10 new species 2017

This year’s list includes a spider and an ant with names drawn from popular books, a pink katydid and an omnivorous rat.

Denmark’s never-ending May twilights

Happening now in Denmark: “bright nights,” when the sun is never far below the horizon. Photographer and videographer Adrien Mauduit tells the story and provides stunning imagery.

2nd-warmest April and year-to-date

And, at both the poles, sea ice extents were at or near record low levels, according to the National Oceanic and Atmospheric Administration.

Humans and pufferfish share teeth genes

Our teeth evolved from the same genes that make the bizarre beaked teeth of the pufferfish, according to new research.

Alligator’s bellow communicates size

For an alligator, in both love and war, it’s good to be big . An alligator’s bellow communicates just how big it is.

NASA camera views sunglint from Earth

You’d expect sunglint from an ocean or other body of water. But the camera caught some glints over land as well. A new NASA video explains how scientists solved the mystery.

The oldest signs of life on land yet

Fossils found in Australia – in ancient hot spring deposits – have pushed back the earliest known evidence for land-based microbial life to 3.48 billion years.

Lake Baikal: Earth’s deepest, oldest lake

Controversy surrounds construction of hydropower stations on a river that feeds deep, ancient Lake Baikal.

Drought is gone from much of US

At the end of April, just 6% of the United States was afflicted by drought. That’s a substantial turnaround from a few years ago.

What makes a red rainbow?

Red rainbows happen when the sun is on the horizon. They’re created in much the same process that causes a sunset or sunrise to look red.

Video teaser: Noctilucent cloud season

Noctilucent clouds – aka night-shining clouds – can be seen at high latitudes in summer, typically beginning for northern latitudes in late May. French photographer Adrien Mauduit in Denmark assembled his best 2016 photos into a wondrous video.

Why did Tsavo lions eat people?

In 1898, a pair of lions ate 135 people at a railroad camp in Kenya. Scientists have analyzed microscopic wear on the lions’ teeth to find out why.

Earth clouds from space

New from NASA, a short video tour of unusual and beautiful clouds observed from space.

What’s the birthstone for May?

Happy birthday May babies! Your birthstone, the emerald, is a type of beryl colored green by chromium. Perfect emeralds are among the rarest of gemstones.

Why birds smash into windows

Up to 1 billion birds die each year in the U.S. due to collisions with windows. Why do birds slam into windows, and what can you do to prevent it?

Why cats can’t resist (even a phony) box

Twitter has been blowing up with posts on cats’ attraction to taped squares on the ground. An animal behavior expert explains what draws Fluffy to the #CatSquare.

Happy World Penguin Day

Antarctica has 12 million penguins and 5 penguin species, according to a new report released today. But at least 2 penguin species have recently and significantly declined.