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Credit: Peter Wienerroither
Tonight | Apr 12, 2014

Brightest Mars in six years on eclipse night

Earth passed between Mars and the sun on April 8. Our two worlds are closest on April 14. On that night, Mars is near the moon at the time of a total eclipse!

Science Wire | Apr 11, 2014

Beauty from chaos on Mars

Catastrophic flooding is thought to have created the heavily eroded Osuga Valles on Mars … and the features within it.

Artist's illustration via NASA/JPL-Caltech
Science Wire | Apr 10, 2014

Astronomers may have spotted the first exomoon!

If it’s true this distant planet has a moon, the moon would weigh less than Earth, and the planet would be more massive than Jupiter.

During a total lunar eclipse, the moon looks red.
FAQs | Apr 10, 2014

How to watch a total eclipse of the moon

A total lunar eclipse is one of the most dramatic and beautiful – and easiest-to-view – of all astronomical events. There’s one coming up on the night of April 14-15.

Artist's concept of asteroid collision via NASA
Science Wire | Apr 09, 2014

Cataclysmic asteroid impact some 3.26 billion years ago

Scientists have reconstructed a collision between the early Earth and an asteroid. It dwarfed the event that caused dinosaurs to go extinct 65 million years ago.

The planetary nebula Abell 33 captured using ESO's Very Large Telescope
Science Wire | Apr 09, 2014

Star aligns with planetary nebula to create diamond ring

It looks like the diamond ring effect seen during total solar eclipses. It’s really a distant, dying star and its shell of gas, with another star in front of it.

Photo Credit: jasonb42882
FAQs | Apr 08, 2014

Why is Mars sometimes bright and sometimes faint?

The brightness of Mars in our sky depends on where our two planets are in orbit around the sun.

Science Wire | Apr 07, 2014

Astronomers make most precise measurement yet of expanding universe

A new analysis says that 10.8 billion years ago, the universe was expanding by one percent every 44 million years.

Sentinel-1A liftoff
Blogs | Videos | Apr 07, 2014

If you could ride a rocket to space, here’s what you’d see

Cameras mounted on the upper stage of a Soyuz rocket last week looked earthward during a satellite launch.

View full size. This is a Hubble image of the most massive cluster of galaxies ever seen to exist when the universe was just half its current age of 13.8 billion years. The cluster contains several hundred galaxies. Image Credit: NASA, ESA, and J. Jee (University of California, Davis)
Science Wire | Apr 04, 2014

Biggest galaxy cluster bigger than thought

El Gordo – the largest galaxy cluster in the universe – is about 3 million billion times more massive than our sun, roughly 43 percent more massive than earlier estimates.