Could a mysterious object in our solar system actually be an alien probe investigating Earth? DETAILS: http://bit.ly/2RIu02S | FOX 5 NY

The search for life out there begins right here, in some of Earth’s most extreme environments. In the fourth episode of our documentary series Our Alien Earth, NASA astrobiologists explore beneath the volcanoes of Hawai’i to advance our search for life on other worlds. Watch today: https://go.nasa.gov/4oWEg6D | NASA - National Aeronautics and Space Administration