Why do we see illusions?

In this video, neuroscientist Mark Changizi explains why optical illusions occur

Meet Zoe, a virtual talking head that can express emotion

An expressive avatar like this one might someday serve as a digital personal assistant or replace texting with face messaging.

Robot hand ties shoelaces and deals cards

In this video, Nigel Ackland demonstrates how his new robotic hand allows him to do ordinary things with extraordinary technology.

Auroras seen at high and mid-latitudes this weekend

As expected, the March 15 coronal mass ejection or CME from the sun caused auroras, or northern lights, at high and mid latitudes.

See Jupiter near moon in daytime sky on March 17 or 18

March 2013 offers the best chance for the next 12 years to see Jupiter near the moon in a blue daytime sky.

Favorite photos of Comet PANSTARRS

Your photos - the best photos - the most recent photos - of this wonderful comet, now visiting the March 2013 skies as seen throughout the world.

Party at Stonehenge. Date 2,500 B.C.

Stonehenge may be older and may have had a different function than previously thought, according to new research from British archaeologists.

Video: 15,000 volts of electricity into a plywood board

What happens when you apply 15,000 volts of electricity to a wooden board? Something quite spectacular.

Video: Harlem shake lab edition

Video of students at Northwestern University doing the Harlem Shake in lab.

Man reunites with gorilla after five years apart

Conservationist Damien Aspinall reunites with the gorilla he raised, five years after the gorilla was released into the wild.