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The Vela supercluster in its wider surroundings. Image via Thomas Jarrett (UCT).

A new major supercluster of galaxies

The Vela supercluster had gone unnoticed due to its location behind the plane of the Milky Way, where dust and stars obscure the view.


What happens if the sun disappears?

Some things that would happen here on Earth if our giant source of heat and light were to vanish from the sky, and how long it would take.


Great Valley found on Mercury

Scientists have discovered a Great Valley on Mercury, hundreds of miles long and sunken by as much as 2 miles (3 km) below the surrounding terrain.

Image Credit: NASA/JHUAPL/SwRI

A slushy ocean beneath Pluto’s heart?

A bulging, viscous, liquid ocean may lie beneath Pluto’s heart-shaped Tombaugh Regio. If it exists, it solves a longstanding puzzle about this region.

Sun halo captured on June 6, 2016 by Amy Gray in Aiken, South Carolina.

Why a halo around the sun or moon?

A large ring or circle of light around the sun or moon is called a 22-degree halo by scientists.

Asteroid collision, via the AIM mission.

100 scientists say yes to asteroid mission

Scientists have signed an open letter in support of increased knowledge of Near-Earth Objects (NEOs), whose orbits carry them near Earth. You can sign it, too.


Super effect on us from a supermoon?

A supermoon’s pull of gravity creates higher-than-usual tides. But gravity doesn’t affect a human body as much as it does an ocean tide.

Sun's path through the zodiac.

What is the zodiac?

The zodiac is defined by 12 constellations that lie along the annual path of the sun across the sky.

Erik Verlinde of University of Amsterdam at the 29th Jerusalem Winter School in Theoretical Physics, 2010, via YouTube.

No need for dark matter?

Erik Verlinde just released the latest installment of his new theory of gravity. He now says he doesn’t need dark matter to explain the motions of stars in galaxies.

Image via NASA/JPL-Caltech/Space Science Institute

Watch summer clouds on Titan

Time-lapse by the Cassini spacecraft shows methane clouds moving across northern regions of Saturn’s largest moon, Titan, on October 29­­­­ and 30.