Ocean Found on Another Jupiter Moon -- This time it's Ganymede

In a teleconference today, NASA announced that through observations made by the Hubble Telescope, team of scientists led by Joachim Saur of the University of Cologne has found evidence that suggests a salty ocean under the ice surface of Jupiter's largest moon, Ganymede. They suspected since the 1970s that an ocean existed under the surface of Ganymede based on scientific models, but this is some of the first direct evidence of that ocean.

The ocean is believed to be 60 miles deep, which is 10 times deeper than the deepest part of Earth's oceans.

NASA’s Hubble Space Telescope has the best evidence yet for an underground saltwater ocean on Ganymede, Jupiter’s largest moon. The subterranean ocean is thought to have more water than all the water on Earth's surface.

Identifying liquid water is crucial in the search for habitable worlds beyond Earth and for the search of life as we know it.

“This discovery marks a significant milestone, highlighting what only Hubble can accomplish,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at NASA Headquarters, Washington. “In its 25 years in orbit, Hubble has made many scientific discoveries in our own solar system. A deep ocean under the icy crust of Ganymede opens up further exciting possibilities for life beyond Earth.”

NASA's Hubble Observations Suggest Underground Ocean on Jupiter's Largest Moon




Also interesting is that Ganymede is the only moon known to have its own magnetic field which creates auroras at the moon similar to Earth's auroras. Here is additional background information on Ganymede, it's magnetic field, and auroras:

Hubble's View of Ganymede -- Press Conference Briefing Materials

And I'm still wondering why NASA decided to send a probe to study Pluto, when we have moons with vast oceans of liquid water much closer than pluto.

originally posted by: muse7
And I'm still wondering why NASA decided to send a probe to study Pluto, when we have moons with vast oceans of liquid water much closer than pluto.

Getting a sample of that water may be difficult...

...well, except for gettin a sample of the salty water of Saturn's Moon Enceladus, which is known to have organic compounds in that water. The water from the seas under Enceladus are being shot into space via the geyser's at the moon's southern hemisphere, just waiting for us to come along and grab a sample of that water shooting into space, which could be brought back to earth for a detailed analysis.

I digress -- and run the risk of hijacking my own thread here, but NASA astrobiologist Chris McKay has suggested such a sample return mission from Saturn's Moon Enceladus a couple of years ago. Now with the new discovery (there are other threads on it) that Enceladus may also have hyrdrothermal vents at the bottom of its seas makes the idea even more exciting.

Such a sample return mission would take a while, and might be relatively costly (simply due to the need to have a sample craft come back to earth), but it is technologically feasible today, and far easier than trying to melt/drill through the surface of Europa or Ganymede. Supposedly, Europa may have similar plumes of water reaching into space, but nothing like the scope of Enceladus.

Oh my. Now I feel like we're just wasting our time, maybe we just didn't know about it yet? But intriguing question! a reply to: muse7

a reply to: muse7

What does that have to do with the mission to Pluto? We shouldn't study any other body farther than Jupiter and its moons, is that what you're suggesting? Why? We can send more than one probe out into space at a time.

Less talk, more suicide missions to Ganymede.

One will eventually be successful out of 1,000,000 attempts.

Gotta crack a few eggs to make an omelet right?

Thanks for the info!

S+F

a reply to: muse7

And I'm still wondering why NASA decided to send a probe to study Pluto, when we have moons with vast oceans of liquid water much closer than pluto.

And I`m wondering why we can`t send probes to all of the targets. Bit less funds into military and bit more into exploration of space would be nice.

originally posted by: Op3nM1nd3d
a reply to: muse7

And I'm still wondering why NASA decided to send a probe to study Pluto, when we have moons with vast oceans of liquid water much closer than pluto.

And I`m wondering why we can`t send probes to all of the targets. Bit less funds into military and bit more into exploration of space would be nice.

I'd love for them to send probes to study every planet too, but the funds available to NASA aren't the same as those available to the military.

All I'm saying is that right now they'd be better off spending their money on developing a probe to go out and study some of these moons with water on them instead of sending a probe to study a planetoid in the far reaches of the solar system.

a reply to: muse7

Yeah I get you. I just wanted to give a hint where the real problem lies

Still I think the governments will come to realise how valuable can be space exploration once they hit a jackpot on one of these planets and moons.

Jupiter and Saturn's moons are where it's at. We should be sending multiple probes there now to all of them.

I still think the Pluto mission was good and I'm excited to see the close ups and find out what we learn there, but next up should be these moons.

a reply to: muse7
There's already a mission proposed to do just that without having to abandon all other exploration.
www.jpl.nasa.gov...

i,ll guarantee that pluto thows up a few surprises also so going there won,t be a waste of time.

i,ll bet pluto is also more active than they think and its going to stump them how a planet that far out is as active as it is.

a reply to: Soylent Green Is People

If we're hearing this now, the conspiracy nut in me wonders what the new information is that we don't know.

On topic, this is great news. SnF!!

Not surprising. The large planets have saved Earth from being bombarded over the years. If it's true that our own water was brought by comets ... then at least some of that bombardment would have taken water to other planetary bodies too.

Ganymede is a large Moon; in fact, I'd bet it is a planet that was caught by Jupiter's magnetic field during its formation. So now we have multiple moons in the Solar system with confirmed oceans: Ganymede, Europa, Titan, and Enceladus. Ceres may also have a subsurface ocean. Exciting........!

A lot of places to choose to live. Let's colonize the galaxy.
Future looks bright and somber at the same time. Imagine the countries fighting to get hold of the resources of those places.

originally posted by: ketsuko
Not surprising. The large planets have saved Earth from being bombarded over the years. If it's true that our own water was brought by comets ... then at least some of that bombardment would have taken water to other planetary bodies too.

The idea that water on Earth came from comets is being challenged; some scientist say Earth's water may have come from asteroids. For example, Ceres is know to consist of a lot of water. The water ice-rich moons of Jupiter (Europa, Ganymede, and Callisto) may have formed out of the same materials (in the same general location in the Solar System) in which Ceres formed. The same type of asteroids made up of the materials that formed Ceres and the major moons of Jupiter may have collided with an early Earth, bringing water. Comets, on the other hand, were formed in the outer solar system.

Data from Rosetta and Comet 67P indicate that it was the wrong type of water -- i.e., too high a ratio of heavy water (water containing a larger ration of deuterium, which is a heavy isotope of hydrogen). This is leading some scientists to wonder if most comets have the wrong type of water; therefore were not the main contributors to Earth's water.

#RosettaWatch: Comet water is not like Earth's


However, the data on this overall is conflicting, because a spectral analysis of the water in the tail of another comet -- Comet Hartly 2 -- shows that its water is similar to earth's water :

A comet starts to tell its watery tale


So, while the data from Rosetta suggests that scientists may need to think about refining their theories about the origin of water on Earth, it is also clear that that the sample size of comets analyzed thus far id too small to make any real determination.