Here’s our beautiful blue marble as seen by NASA’s OSIRIS-REx spacecraft on Sept. 22, 2017 from a distance of 106,000 miles (170,000 km). It had just completed a gravity-assist flyby of Earth—a little 19,000 mph “once around the block” that gave the spacecraft an 8,500-mile-an-hour speed boost necessary to adjust its course toward Bennu, the asteroid target of its mission.
It’s no secret that Earth’s ocean is filled with life, much of it still a mystery or totally unknown to science. But what about the ocean on other worlds? I’m not talking about sci-fi planets or suspected alien Earths around other stars, but right here in our own solar system, where an ocean even deeper than ours lies hidden beneath a global shell of ice.
Scientists believe there is an ocean hidden beneath the surface of Jupiter’s moon Europa. In the video above, NASA-JPL astrobiologist Kevin Hand explains why scientists are so excited about the potential of this ice-covered world to answer one of humanity’s most profound questions: does life exist beyond Earth?
To learn more about Europa click here, and see the latest enhanced version of a Galileo image of Europa below:
It’s been suspected for nearly a decade that Saturn’s 315-mile-wide moon Enceladus harbors a hidden ocean beneath its frozen crust, thanks to observations by the Cassini spacecraft of icy plumes spraying from its southern pole, and now scientists have even more evidence supporting its existence: Doppler measurements of the moon’s gravity taken during Cassini’s flybys show variations indicative of a subsurface southern sea as deep as the Pacific’s Mariana Trench!
“Attempt no landings there?” Ok, FINE. We’ll just fly a spacecraft through Europa’s newly-discovered plumes and get a taste of its underground ocean that way!
Because it has them, and so we could.
This was the big news from NASA, ESA, and Hubble researchers today: Jupiter’s ice-covered moon Europa (yes, the one from 2010) has Enceladus-like plumes of water vapor near its south pole. What’s more, these plumes appear to vary depending on the moon’s distance from Jupiter; the giant planet’s gravity is “squeezing” Europa, causing the plumes to shut off when it’s closer and turn on when farther away. Now I’m no scientist, but I’d call that pretty solid evidence for a subsurface ocean… and darn good reason to scramble some exploration missions out to Europa tout de suite!