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Another Planet 9 search! You can help

This one will use images of the sky visible from Earth’s Southern Hemisphere. You can help from anyplace on the globe. The search is for a 9th major planet in our system, nicknamed Planet 9.

Super halos around very young galaxies

Astronomers directly observed a pair of Milky-Way-like galaxies, seen when the universe was 8% of its current age. They were excited to find the young galaxies surrounded by huge halos.

New map of space dust in 3-D

Sure, we’re all collections of space dust. But astronomers also want to study it in order to understand how space dust in our Milky Way obscures starlight from afar.

Does Mars sometimes have rings?

It’s possible that Mars’ closer moon – Phobos – might alternate between becoming a planetary ring and clumping together to form a moon.

Star’s death spiral into black hole

What happens when a star with about our sun’s mass spirals into a black hole? With the distant event known as ASASSN-14li, astronomers have figured out some details.

What makes a pulsar pulse?

Hear the word “pulsar” and wonder what it is? Take 95 seconds to watch this video from NASA Astrophysics.

7 Earth-sized worlds? What we really see

A reality check from astrophysicist Brian Koberlein on what we actually see of the 7 recently discovered Earth-sized planets orbiting the star TRAPPIST-1.

Fizzy lakes for Saturn’s moon Titan?

Bright features – informally known as “magic islands” – seem to appear and disappear in a Titan sea. A new study shows that bubbles could, potentially, be the cause.

Bodies freed from gravity’s grip

Life on Earth is used to gravity. So what happens to our cells and tissues in space?

Where was dark matter in early universe?

Surprising new observations of distant galaxies suggest that dark matter was less influential in the early universe than it is today.

Celestial spiral is a double star

It’s not a spiral galaxy. It’s a double star system seen from Earth to create a spiral shape in a shell of gas.

Closest-yet star to black hole

Astronomers have found a star that whips around a black hole about twice an hour. That’s a very close orbit, possibly the tightest orbital dance ever witnessed for a star and black hole.

Back-to-back Mars dust storms

In the past few weeks, the Mars Reconnaissance Orbiter has reported 2 dust storms that sprang up in Mars northern hemisphere, then blew up to continent-size upon shifting southward.

Total eclipse of sun: August 21, 2017

All you need to know about the 1st total solar eclipse visible from the contiguous U.S. since 1979, from eclipse master Fred Espenak.

Moon shadow path in 2017 solar eclipse

Fly along with the moon’s shadow in this NASA video depicting the path of the August 21, 2017 total eclipse of the sun.

Today in science: Discovery of Uranus

It was the first planet found since ancient times. William Herschel noticed it in 1781 during a routine survey of the stars.

When galaxies collide, black holes eat

When our Milky Way galaxy and neighboring Andromeda galaxy collide, supermassive black holes will have a feast!

Cassini shows strange Saturn moon Pan

Wonderful Cassini spacecraft – now in its final year orbiting Saturn – shows us a tiny, walnut-shaped shepherding moon.

Comet Encke nearest sun March 10

Faithful Comet Encke is one of the shortest-period comets known. Its frequent returns near the sun helped reveal the true nature of comets.

Today in science: Yuri Gagarin’s birthday

Yuri Gagarin was a Russian pilot who became the first human to travel to space, in 1961. His story … plus links to a Yuri’s Night near you.