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Did Ceres once have an ocean?

Two recent studies explore the possibility of an ancient ocean on dwarf planet Ceres, largest world in the asteroid belt. If it existed, what happened to it? And could Ceres still have liquid water today?

A potential human habitat on the moon?

A new study says a hole in the moon’s Marius Hills region is the skylight of an underground lava tube large enough to house a city.

Webcam surveys high clouds on Mars

A webcam on ESA’s Mars Express has acquired an unprecedented catalog of more than 21,000 images, providing a global survey of unusual, high-altitude, martian clouds.

Fornax Galaxy Cluster reveals its secrets

This new 2.3-gigapixel image of the Fornax Galaxy Cluster – one of the largest images ever released by European Southern Observatory – might make you feel small.

How the universe creates gold

Finally, scientists know how the universe makes gold. They’ve seen it created in the cosmic fire of 2 colliding stars via the gravitational wave they emitted.

Pluto: Preparing for the perfect alignment

Pluto will cross the plane of the ecliptic – the Earth-sun plane – in 2018. This hasn’t happened since 1931, near the time of the Pluto’s discovery. Astronomers are getting ready!

Artificial intelligence finds 56 new gravitational lens candidates

Using the same technology Tesla is using to teach cars to drive themselves, European astronomers are using artificial intelligence to seek out and find many new gravitational lenses.

Reliving Cassini’s final moments

“Cassini managed to survive for 91 seconds in this epic battle, before tipping over backward during the last 8 seconds and then finally losing radio contact with Earth.”

What is an astronomical unit?

Astronomers use astronomical units – or AU – to describe solar system distances. Definition of AU here. Also, mean distances in AU to prominent solar system objects.

Astronomers confirm Earth has an asteroid buddy

It’s the best and most stable example to date of a near-Earth companion, or “quasi-satellite.” It’s a small asteroid called 2016 HO3. It travels along with Earth in orbit around the sun.