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Top stories: Pluto is alive, 'Big Bird' the dinosaur, and buckyballs in space
(Left to right) Shao Chuang; NASA/JHU; APL/SWRI

Top stories: Pluto is alive, 'Big Bird' the dinosaur, and buckyballs in space

Pluto is alive—but where is the heat coming from?

This week, NASA’s New Horizons spacecraft barreled past Pluto. Scientists will be collecting data until late 2016, but so far they report finding towering mountains of water ice rising above smooth plains covered in veneers of nitrogen and methane ice. The finding is sending scientists back to the drawing board as they try to figure out where the heat needed for such geological mountain building is coming from.

Check out Science’s full coverage of NASA’s New Horizons Pluto flyby.

New report card on global HIV/AIDS epidemic

A huge new report on the global HIV/AIDS epidemic celebrates the “extraordinary progress” in both treatment and prevention over the past 15 years. With updated country-by-country HIV and AIDS figures, the new UNAIDS report gives us more insight on the epidemic and urges the world to crank up a response.

'Big Bird' dino: Researchers discover largest ever winged dinosaur

When we see birds winging their way across the sky, we are really looking at living dinosaurs—the only lineage of these mighty beasts that survived mass extinction. Yet before they went extinct, many dinosaurs sprouted wings themselves. Researchers now report finding the largest ever winged dino in China. This “Big Bird” dinosaur lived 125 million years ago and weighed 20 kg (44 lb)—and it probably never flew.

Strange new subatomic particles discovered at atom smasher

Physicists have finally found the pentaquark—an exotic subatomic particle made up of five quarks. Researchers at CERN, home of the Large Hadron Collider, claim to have found conclusive evidence for the existence of pentaquarks, and say the discovery may help us understand how matter is built up from quarks as well as provide insight into how stars are formed.

Yes, there really are buckyballs in space

The space between the stars is so hostile that most astronomers once thought it couldn't possibly harbor something as fragile as molecules. Nevertheless, chemists report buckyballs—complex molecules with 60 carbon atoms—do indeed exist in deep space. Astronomers suggest that because our solar system arose from interstellar material, some of the carbon now in our bodies once existed in the form of buckyballs.

Which movies get artificial intelligence right?

Hollywood has been tackling artificial intelligence (AI) for decades, from Blade Runner to Ex Machina. But how realistic are these depictions? Science asked a panel of AI experts to weigh in on 10 major AI movies —what they get right, and what they get horribly wrong. We also rank the movies from least to most realistic.