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Gravitational anomaly seen in lab crystal

An exotic effect in particle physics, theorized to occur in immense gravitational fields — near a black hole, or in conditions just after the Big Bang — has been seen in laboratory crystal.

How to watch Shark Week

This is a week of dueling shark-athons on television. A biologist advises viewers to take what they see with a large grain of sea salt.

Synchronized symphony of fireflies

This video shows a timelapse journey through Smoky Mountains National Park during world’s largest gathering of synchronized fireflies. Beautiful!

Why fireflies light up

A firefly’s familiar glow is caused by chemical reaction. Explanation here, plus many wonderful firefly photos.

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New moon comes on July 23

This July 23 new moon is the last one before the much-anticipated Great American Eclipse!

Watch for Delta Aquariid meteors

They’re the reason it’s fun to begin watching for meteors in late July. The Delta Aquarid shower is long and rambling and overlaps with the Perseids.

Hubble sees Phobos orbiting Mars

This image and video aren’t artists’ illustrations. They’re from a real time-lapse sequence of images – acquired by the Hubble Space Telescope – of the tiny moon Phobos orbiting Mars. Cool!

How close will asteroid 2012 TC4 come?

Asteroid 2012 TC4 might give Earth a close shave in October, 2017. Or the asteroid could pass more distantly. Astronomers are keen to observe it now, to learn more about its orbit.

Where’s the moon? Waning crescent

Will you see the moon Saturday morning from the Americas? Not likely, especially as the line of moonrise, and sunrise, edge farther west today. New moon will come on July 23 at 9:46 UTC.

Star of the week: Vega

One of the prettiest stories in all skylore surrounds this star. “On the 7th night of the 7th moon … “

Video: Moon hoax not

SG Collins explains why the Apollo moon landings on the moon in the late 1960s and early ’70s couldn’t have been faked.

Today in science: 1st footsteps on moon

Today is the 48th anniversary of humanity’s historic first steps on the moon. The story in pictures, here.

A shadow-band project for August 21

Shadow bands are elusive ripples of alternate light and dark, flitting over the ground or the sides of buildings during a total solar eclipse. How to take part in an International Shadow Band Campaign during the August 21 eclipse.