A planet-size object that possibly once visited the solar system may have permanently changed our cosmic neighborhood by warping the orbits of the four outer planets, a new study suggests.

Anyone who looked up at the sky on Wednesday night may have caught a glimpse of an impressive sight: all the planets of our solar system on display. The phenomenon — also known as a "planet ...

Watch this video to find out more about the Earth, planets in our Solar System and other planets far off in outer space. From up here on the International Space Station I get a great view of Earth.