Scientists Think Mars Once Had Water. So What Happened to It? Mars may have had a core similar to Earth’s. It’s possible that when it diminished, the planet’s water went with it. Facebook Prev Article Next Article Space Checkout these cool gadgets... Related Posts NASA Begins Accepting Astronaut Applications for First Manned Mission to Mars Russian Rocket Tumbles Back To Earth How to Put On a Space Suit NASA’s Staff Sniffer Extremely Large Telescope Could Spot Alien Life Space Elevator – Science Fiction or the Future of Mankind?