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View Full Version : Europa - Hubble observations suggest geysering water



Colin Robinson
2014-Jan-25, 03:49 AM
Last month the Hubble Space Telescope detected an ultraviolet hotspot on Europa, with wavelengths of hydrogen and oxygen atoms. Scientists have interpreted this observation as a likely indication of water geysering out of Europa on a large scale, as occurs on Saturn's moon Enceladus.

Washington Post report (http://www.washingtonpost.com/national/health-science/hubble-space-telescope-sees-geysers-on-jupiters-moon-europa/2013/12/12/b6f780ac-62c8-11e3-a373-0f9f2d1c2b61_story.html)

Phil Plait's blog (http://www.slate.com/blogs/bad_astronomy/2013/12/12/europa_possible_geyser_observed_using_hubble.html)

While there is nothing new in the idea that Europa has a subsurface ocean of liquid water, this seems to be the first indication that water is flowing out through the surface. Which would make it possible to sample water from Europa's subsurface without having to burrow through kilometers of ice.

As Phil Plait says:


It’s hard to say whether this makes it more likely that there are little Europan fishies swimming around down there, but it does mean it’ll be easier to take a look.

Selfsim
2014-Jan-25, 10:41 AM
No mention of anything more interesting than just hydrogen and oxygen(?)

Noclevername
2014-Jan-25, 11:24 AM
No mention of anything more interesting than just hydrogen and oxygen(?)

AFAIK not with the frequencies of light they were using.

Local Fluff
2014-Jan-25, 01:59 PM
It aggravates me a bit that when such a discovery is made, a probe isn't hastily made to flyby it with a telescope spectrometer suited for observing those hydrogen plumes. And by chance maybe capture some of the ejecta it flies through, for better chemical analysis. Voyager passed by Jupiter within 2 years of launch. The next Europa mission is dated something in the 2030's, which is so very far away that it certainly will be canceled for some obscure political reason, or postponed to the 2040's, or anyway will be outdated and irrelevant even if it ever happens. Planning anything for the 2030's is simply not a plan at all.

Water is hysterically searched for on the Moon and on Mars. They hardly find a tiny bit of it. But water is spewing out of the moons in the outer Solar system.

Colin Robinson
2014-Jan-25, 10:20 PM
It aggravates me a bit that when such a discovery is made, a probe isn't hastily made to flyby it with a telescope spectrometer suited for observing those hydrogen plumes. And by chance maybe capture some of the ejecta it flies through, for better chemical analysis.

NASA scientists like John Grunsfeld and Carolyn Porco are talking about a possible mission to sample ejecta from the reported geyser(s). (See the Washington Post report cited in the OP.)

It would certainly be easier than some earlier proposals for studying the waters of Europa, e.g. by means of a nuclear-powered heater that would melt its way down thru kilometers of ice.

But any space mission takes time and planning, not to mention political support.

Colin Robinson
2014-Jan-25, 10:35 PM
No mention of anything more interesting than just hydrogen and oxygen(?)

Perhaps the findings became more interesting when the scientists asked why.

Why would there be substantially more hydrogen and oxygen atoms in one particular place on Europa?

Selfsim
2014-Jan-26, 02:00 AM
Perhaps the findings became more interesting when the scientists asked why.

Why would there be substantially more hydrogen and oxygen atoms in one particular place on Europa?Well that's pretty clear isn't it?
Water seems to fit the bill!

What I'm asking is: was there anything else mixed in with it, (like organics, or a bit of dirt or somethin'), or is it just pure water?

Noclevername
2014-Jan-26, 02:08 AM
Well that's pretty clear isn't it?
Water seems to fit the bill!

What I'm asking is: was there anything else mixed in with it, (like organics, or a bit of dirt or somethin'), or is it just pure water?

They haven't even found water molecules yet, technically it's just the separate H2 and O2 spectra.

Colin Robinson
2014-Jan-26, 02:43 AM
Well that's pretty clear isn't it?
Water seems to fit the bill!

What I'm asking is: was there anything else mixed in with it, (like organics, or a bit of dirt or somethin'), or is it just pure water?

Judging from the Washington Post report, nothing other than the hydrogen and oxygen has been detected yet in the newly discovered "hot spot", but NASA people like John Grunsfeld are (like you) very interested to know whether organics are mixed in.

Edit to add:

The article does mention that organic material in geysers would provide an explanation for brown areas on Europa's surface ice, as photographed by space probes.

Noclevername
2014-Jan-26, 11:46 AM
Could the brown patches be inorganic? There have been organic compounds found in space dust, but has the dust around Jupiter (such as its rings) been observed to have organics?

Spacedude
2014-Jan-26, 04:16 PM
If it were technically feasible? it would be neat if a geyser sample collection craft could swing by Europa first and then use Jupiter's gravity to propel the probe to Saturn to later collect a separate sample from the geysers on Enceladus before returning to Earth. 1 bird cheaper than 2.

Local Fluff
2014-Jan-26, 05:30 PM
If it were technically feasible? it would be neat if a geyser sample collection craft could swing by Europa first and then use Jupiter's gravity to propel the probe to Saturn to later collect a separate sample from the geysers on Enceladus before returning to Earth. 1 bird cheaper than 2.
All four outer planets are almost as far away from each other as they get right now. Fastest thing happening there is Jupiter with its 11 year orbit, in about 6 years it will be somewhat lined up with Saturn. Anyway, it'll probably just be water anyway, it's the second most common molecule in the universe. And it can be identified from a distance by telescopes with spectrometers. A mission there should land next to a geyser, not just collect a glass of water.
http://www.theplanetstoday.com/

Colin Robinson
2014-Jan-26, 10:11 PM
Could the brown patches be inorganic?

Yes, there is a theory that the coloration is due to sulphur compounds.


There have been organic compounds found in space dust, but has the dust around Jupiter (such as its rings) been observed to have organics?

Not the rings, as far as I know. There is some spectrographic evidence suggesting organic compounds on two of Jupiter's moons: Callisto and Ganymede. The presence of free oxygen in Europa's atmosphere implies a radiation-driven chemical process in the surface ice which is likely to also produce organics, at least simple ones such as formaldehyde.

Colin Robinson
2014-Jan-27, 12:40 AM
All four outer planets are almost as far away from each other as they get right now. Fastest thing happening there is Jupiter with its 11 year orbit, in about 6 years it will be somewhat lined up with Saturn. Anyway, it'll probably just be water anyway, it's the second most common molecule in the universe. And it can be identified from a distance by telescopes with spectrometers. A mission there should land next to a geyser, not just collect a glass of water.
http://www.theplanetstoday.com/

The water molecule is common, but liquid water is another question -- it is a lot harder to find beyond Earth than water vapor or ice.

Actually Earth was the only world known to have liquid water, until we got evidence for Europa's subsurface ocean from the Galileo mission. Even though the evidence was indirect, and the hypothesized ocean was a long way down, scientists were understandably excited.

The thing is, all known organisms, including extremophiles, have liquid water in their cytoplasm when they are growing and reproducing. Some can survive in dry form as spores, but they cannot reproduce until they get a drink.

Local Fluff
2014-Jan-27, 03:44 PM
The water molecule is common, but liquid water is another question -- it is a lot harder to find beyond Earth than water vapor or ice.
Hard to find, yes, because if it is common it is below thick ice, covered and mixed with other stuff.
But it is seriously considered that objects like Ceres, three large Jovian moons, Titan, Enceladus, Triton and the double-dwarf planet Pluto/Charon could have (slushy) liquid water below. It is however hard to detect. Geysers give a clue. And if three such objects now have observed water geysers, it helps it make seem common. As would some seismic instruments landed on the surfaces of such objects. Even here on Earth the question of subsurface life is only marginally explored. One sample from Lake Vostok is maybe the most prominent discovery of life below thick ice.


The thing is, all known organisms, including extremophiles, have liquid water in their cytoplasm when they are growing and reproducing. Some can survive in dry form as spores, but they cannot reproduce until they get a drink.
Liquidater is the way to go, I think. But as an aside as you mention it:
Don't bacteria get more active in micro gravity, because they "feel" being in micro gravity as similar to being suspended in liquid water? I've read that's a problem onboard LEO space stations. Don't know if that could wake up spores, though. My main point is that liquid water could be common under icy surfaces. Oceans don't need gaseous atmospheres, they'll make do with solid face surfaces too. We might be the freak around here, having liquid water on a planet surface. Together with Titan having some liquid methane on its surface, although the bipolarity of water making it much more useful for life.

Aristarchusinexile
2014-Jan-27, 03:49 PM
It aggravates me a bit that when such a discovery is made, a probe isn't hastily made to flyby it with a telescope spectrometer suited for observing those hydrogen plumes. And by chance maybe capture some of the ejecta it flies through, for better chemical analysis. Voyager passed by Jupiter within 2 years of launch. The next Europa mission is dated something in the 2030's, which is so very far away that it certainly will be canceled for some obscure political reason, or postponed to the 2040's, or anyway will be outdated and irrelevant even if it ever happens. Planning anything for the 2030's is simply not a plan at all.

Water is hysterically searched for on the Moon and on Mars. They hardly find a tiny bit of it. But water is spewing out of the moons in the outer Solar system.

You could offer billions of dollars to speed things up. Hundreds of tons of water has been found on the moon and on Mars .. not in a liquid state though.

Colin Robinson
2014-Jan-27, 09:25 PM
Hard to find, yes, because if it is common it is below thick ice, covered and mixed with other stuff.
But it is seriously considered that objects like Ceres, three large Jovian moons, Titan, Enceladus, Triton and the double-dwarf planet Pluto/Charon could have (slushy) liquid water below.

Yes.


It is however hard to detect. Geysers give a clue.

Subsurface water is hard to detect, and hard to sample, unless some of it breaks thru the surface.

What I find exciting about Europa's apparent geyser, is the opportunity of looking at a sample of the water under a microscope. There could be organisms. There could also NOT be organisms, but we won't know that till we look.

Enceladus offers a similar opportunity, but it is roughly twice as far away from Earth.


And if three such objects now have observed water geysers, it helps it make seem common.

Three objects with observed water geysers? Besides Enceladus and Europa, where else?

Geysers of nitrogen have been observed on Triton, but not water geysers AFAIK.


Don't bacteria get more active in micro gravity, because they "feel" being in micro gravity as similar to being suspended in liquid water? I've read that's a problem onboard LEO space stations. Don't know if that could wake up spores, though.

Water isn't just the medium living cells like to float about in, it is one of the substances they are made of. A cell consists of liquid cytoplasm plus membranes -- of course, there is much more to a cell than that, but without liquid cytoplasm or without membranes, you wouldn't have a functioning cell at all.


My main point is that liquid water could be common under icy surfaces. Oceans don't need gaseous atmospheres, they'll make do with solid face surfaces too. We might be the freak around here, having liquid water on a planet surface.

Yes, it is starting to look that way.


Together with Titan having some liquid methane on its surface,

Titan not only has liquid methane on its surface, it also has a thick atmosphere, and a diverse and active organic chemistry.

Europa's atmosphere is much thinner, but has molecules of oxygen, which Titan lacks. Europa may or may not have diverse organics, but that hasn't been established yet.

Githyanki
2014-Feb-05, 11:53 PM
Breaking news, they detected chlorophyll.

Selfsim
2014-Feb-06, 12:11 AM
Breaking news, they detected chlorophyll.Yeah sure ..

Noclevername
2014-Feb-06, 12:36 AM
Breaking news, they detected chlorophyll.

Just to clarify, it's a reference to the film 2010.

Selfsim
2014-Feb-06, 01:19 AM
Just to clarify, it's a reference to the film 2010.Which is completely irrelevant ...