Where exactly did water on Earth come from? The answer may surprise you.
As explained in the latest episode of the Youtube science series MinuteEarth, water may have hitched a ride our way on strange space rocks called carbonaceous chondrite meteorites. Just check out the video above.
"Chondrite is just the name given to the class of stony meteoroids that most commonly strike the Earth," Henry Reich, creator of MinuteEarth, says in the video. "But only the carbonaceous chondrites contain water, as well as lots of carbon if you couldn't tell from their name."
See, during our planet's infancy, the early inner solar system was way too hot for frozen or liquid water to exist -- and any water vapor would have been pushed away by solar wind. So water had to come from far beyond the inner solar system, or as Reich puts it, quite literally from out of the blue, to transform Earth into our familiar blue marble.