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Star of the week: Epsilon Lyrae

Binoculars reveal that Epsilon Lyrae is a double star – two stars in one. A telescope shows that each component star is also a double. The double double star!

We are galaxy stuff

A new study – based on supercomputer simulations – reveals that each one of us may be made in part from matter that passes from one galaxy to another.

Gauging Arctic’s summer sea ice melt

This past winter, Arctic sea ice extent sank to a record low for the 3rd straight year. Now, NASA is looking at the summer melt season’s impact on the Arctic’s oldest, thickest sea ice.

Watch launch of new ISS crew July 28

Live launch coverage from Kazakhstan begins at 10:45 a.m. EDT (14:45 UTC). You can also watch the spacecraft dock with the ISS, starting at 5:15 p.m. EDT (21:15 UTC).

More From Latest

How to find Delta Aquarid radiant point

How to spot the radiant point for the Delta Aquarid meteor shower, going on now. Plus … why meteors in annual showers have radiant points.

Awesome beauty of the Eagle Nebula

The Eagle Nebula – aka Messier 16 or M16 – is home to several famous structures, including the Pillars of Creation and the Stellar Spire.

Close shave from an undetected asteroid

Whoosh! Astronomers discovered a small asteroid – now designated as asteroid 2017 OO1 – on July 23. That was 3 days after it passed 1/3 the moon’s distance from Earth.

How many distant comets?

Mysterious long-period comets might be more common – and bigger – than astronomers thought. Studies like this one will help reveal what kind of hazard they might pose.

Haze on Saturn’s horizon

Spectacular recent image from the Cassini spacecraft, now in its Grand Finale year around Saturn, taken from just above Saturn’s cloudtops, showing haze on the planet’s horizon.

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.