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Astronomers complete 1st global asteroid tracking drill

This is only a test. Astronomers report on the TC4 Observation Campaign, which, in October, used a real Near-Earth Asteroid to practice our global response to a potential asteroid threat.

What is the moon illusion?

Ever noticed a rising full moon appear huge on the horizon? It’s called the “moon illusion,” and it’s a trick your brain is playing.

A rare chance to scrutinize a comet’s jet

On July 3, 2016 – as Comet 67P erupted with a plume of dust – the orbiting Rosetta spacecraft happened to pass right through the dust cloud.

What is dark matter?

Cosmologists are heading back to their chalkboards, as experiments designed to figure out the nature of dark matter come up empty.

Small object visits from beyond solar system

This small asteroid (or comet) passed under Earth’s orbit on October 14 at about 60 times the moon’s distance. Now it appears to be heading toward interstellar space again.

How do human genes act in space?

“Looking at gene expression … we really see an explosion, like fireworks taking off, as soon as the human body gets into space.”

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.