Experts have known for a time that Saturn's moon Enceladus was hiding an ocean beneath its icy crust, but up until now, nobody had any idea how expansive it really is. SciShow Space's clip below dates back a year, and while the details about the moon are still on point, it shows the extent to which we miscalculated the staggering size of this body of water.

Comparing the JPL diagram in the clip below to the one at the top of the page, it's easy to see what was left out. Back then, it was expected that the southern pole of the body harbored an under-crust ocean, but it seems we were missing the bigger picture. New information from NASA's Cassini mission shows that this ocean likely wraps around the entirety of Enceladus' core.

While researchers had some grasp on what lay beneath this moon's surface a year ago, the new data has Peter Thomas, lead author of the paper announcing the findings, convinced.

"This was a hard problem that required years of observations, and calculations involving a diverse collection of disciplines, but we are confident we finally got it right."

Keep your eyes and ears open going into next month — Cassini is slated to make another flyby on October 28. NASA notes that "the spacecraft will pass a mere thirty miles above the moon's surface," so we'll likely get a better look at the moon than any we've had yet.

Check out SciShow Space's clip down below and let us know what you think. When the video's over, be sure to share it with your friends on Facebook!