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Image via NASA

Watch spacewalk live August 19

Two ISS astronauts will perform a spacewalk on Friday. NASA TV’s live coverage starts at 6:30 a.m. EDT (10:30 UTC) and lasts about eight hours.

An artist's re-creation of the first human migration to North America. Image via DEA Picture Library / Deagostini / Getty Images

How did humans first reach America?

A new study suggests that the first people to reach America travelled via the Pacific coast rather than through a corridor between two giant ice sheets.

Seventy six of 77 atmospheric scientists responding to a survey agree these are contrails, not "chemtrails."

Atmospheric scientists say ‘no chemtrails’

Is there a large-scale, secret program to spray chemicals into Earth’s atmosphere, resulting in “chemtrails?” Leading atmospheric scientists just say no.

Image via www.sciencealert.com

Physicists confirm a possible 5th force

“If true, it’s revolutionary,” said Jonathan Feng, professor of physics and astronomy at University of California, Irvine and lead author of the new study.

A plate of Enterobacter aerogenes showing the bulls-eye pattern of swarming underneath a stylized clock face. Image via Jiffin Paulose.

The circadian clock in your gut

Our internal circadian clock tells our body when to sleep, wake and eat. New research says that bacteria living in our gut also have their own circadian clocks.

Camp Century doubled as a top-secret site for testing the feasibility of deploying nuclear missiles from the Arctic during the Cold War.

Ice melt may release Cold War-era toxins

Formerly secret Camp Century in Greenland was abandoned beneath ice and snow. But the ice is melting, and biological, chemical and nuclear waste may be released as early as 2090.

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Today in science: 7 minutes of terror

To celebrate the 4-year anniversary of Curiosity rover’s arrival on Mars, here’s a video on the final 7 minutes of its chilling descent on August 5-6, 2012.

Image via Sarah2 / shutterstock / theconversation

Parakeet takeover ahead?

“Parakeets are Britain’s fastest growing bird population and are on a trajectory to global domination.”

Geminid meteor in 2012 by Henry Shaw.

Learn to shoot photos of meteors

Want to try to capture a meteor on film? The first step is planning. The next step is to gather your equipment. Then on to the capture process itself.

Artist's concept of Emirates Mars Mission

Emirates Mars Mission to launch in 2020

The Emirates Mars Mission – which carries the name Hope – will become the first-ever mission to the Red Planet by any Arab country.