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From flying cars and railguns to smartphones and jetpacks — what was once sci-fi can now be found in the real world.

From chatbots giving truly terrible medical advice to facial recognition software incorrectly flagging members of congress as criminals, here are some of the most catastrophic mistakes artificial intelligence has ever made.

From "runaway" black holes shooting across the cosmos to secret planets in our own backyard, space is overrun with mysterious objects that scientists are clamoring to explain. Here are five of the strangest sights in the universe, as well as their possible origins.

The outer solar system is a vast and mysterious place that could be harboring hidden objects we know almost nothing about — from the elusive Planet Nine and baby black holes to interstellar visitors and "planet killer" asteroids.

Reference From 9-foot tall ostriches to albatrosses with gargantuan wingspans, here are some of the biggest birds in the world.

Shipwrecks can reveal information about traded goods and even which rituals people partook in centuries ago. Here's a look at shipwrecks from ancient times found around the world.

Auroras (also called the northern and southern lights) are visible from the ground after powerful solar storms, but these natural light shows look even more majestic from above. Here are 32 spectacular photos of auroras taken from space.

Artificial Intelligence (AI) is set to improve the world for many — but others may lose out.

Parasites can cause a wide range of diseases in humans, ranging from short-term to lifelong.

From planets and moons in our solar system to dying stars and parallel universes, here are some of the far-out places scientists are searching for alien life.