Videos of playlist "PL39_ud5aKSvmp93BY4IqxnHr2Cktfbz-r"
2:50 / Scientists Think Mars Once Had Water. So What Happened to It?
2:19 / Here's How Scientists Will Measure Quakes on Mars
2:50 / Would You Take the One Way Trip to Mars?
2:52 / SpaceX Wants to Send You To Mars. Here's How They Plan to Do It.
2:52 / Testing the Curiosity Rover on Earth
3:14 / Looking For Ancient Martian Lakes
2:25 / Something in the Martian Sand is Explosive!
2:49 / This is How NASA Guides Robots Around Mars
2:57 / First Step In Training For Work on Mars: Go Underwater
1:22 / Engineers Have Already Built Vehicles to Drive on the Martian Surface
1:26 / Scientists Are Designing the Spacesuits We'll Wear on Mars
