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Sun on the sky’s equator

Another great explanation of Friday’s equinox – plus beautiful graphics – from astronomer Guy Ottewell.

A Chinese perspective on autumn

Autumn is connected in Chinese thought with the direction west, considered to be the direction of dreams and visions.

Zap! Biologist measures electric eel’s shock on his own arm

Talk about dedication to science! This biologist stuck his arm into an eel tank – 10 times – to get an accurate measure of an eel’s shock. He said it felt “like touching a horse fence.”

Wildlife Photographer of the Year 2017

Which one would you choose?

Dust devils on Earth and Mars

Researchers spent 5 years studying dust devils in earthly deserts. They said their research has implications for climate and weather on both Earth and Mars and for human health.

Day and night exactly equal at equinoxes?

On the day of an equinox, the center of the sun would set about 12 hours after rising – given a level horizon, as at sea, and no atmospheric refraction.

Irma turns Caribbean islands brown

Wow. Check out these satellite images of Caribbean islands before and after Hurricane Irma

Openings in Antarctic sea ice influence global climate

Heat escaping through openings in sea ice influences sea and atmospheric temperatures and wind patterns around the globe – even rainfall around the tropics, says new study.

Does organic material in comets predate our solar system?

“If cometary organic molecules were indeed produced in interstellar space—and if they played a role in the emergence of life on our planet—might they not also have seeded life on many other planets of our galaxy?”

Our Age of Humans in a galactic context

A proposed new classification system – somewhat like the well-known Kardashev scale for classifying extraterrestrial civilizations – and a new way of thinking about human sustainability on Earth.

Thursday night was fantastic for auroras

Space weather forecasters predicted the possibility of strong geomagnetic storms, resulting in a strong display of the aurora borealis, or northern lights … and they were right!

Human antidepressants found in brains of Great Lakes fish

“Fish are receiving this cocktail of drugs 24 hours a day, and we are now finding these drugs in their brains.”

See an extra-red moon or sun this week?

If you live in the U.S. or Canada, a peculiarly red moon – or very spectacular sunrise or sunset – might be due to smoke from wildfires. Click in for images from Earth and space.

How Harvey churned up, and cooled down, Gulf waters

These maps show how the deluge of fresh rainwater and ocean mixing from hurricane Harvey combined to dramatically alter the surface waters of the Gulf of Mexico.

Dark for 2 years after dino-killing asteroid?

Can you imagine a sky so laden with soot that all of Earth stayed dark for 2 years? New research suggests it happened, at the end of the age of the dinosaurs.

Earliest flying mammals discovered

Two 160 million-year-old fossils discovered in China are the oldest known mammal gliders. “These Jurassic mammals are truly ‘the first in glide.’”

Floods: Not just a coastal issue

As Hurricane Harvey shows, flooding can happen wherever large storms stall and dump lots of rain. A new study finds development is increasing in flood zones far from any coast.

Hidden river once flowed under Antarctica

“Ice, by itself, is only capable of flowing at velocities of no more than tens of meters per year. That means the ice is being helped along. It’s sliding on water or mud or both.”

July 2017 tied with 2016 for hottest July

It was another hot July. Last month was tied with July 2016 as the warmest July in the 137 years of modern record-keeping.

Today in science: Earth from the moon

This is the first photo of Earth from the moon, released in 1966. Later, NASA used modern digital technology to restore the photo to reveal more detail.