26 replies to this topic

[Saru]

Scientists are hoping to send a probe to find signs of life on Jupiter's ice-covered waterworld moon.

Guardian Unlimited said:

scientists have drawn up plans for a mission that could look for life on Europa, a moon of Jupiter that is covered in vast oceans of water under a thick layer of ice. The Europa Clipper would be the first dedicated mission to the waterworld moon, if it gets approval for funding from Nasa. The project is set to cost $2bn.

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[wimfloppp]

Icant see the point.Its to far away to have life as we know it and to cold.

[marcos anthony toledo]

Europa disserve a mission to explore it how about a multination mission to spread the costs don't go it alone NASA.

[Waspie_Dwarf]

wimfloppp, on 18 February 2013 - 03:29 PM, said:

Icant see the point.Its to far away to have life as we know it and to cold.

You haven't been keeping up with the last 20 or so years of discoveries about the moons of the giant planets.

It is believed that Europa and several other moons have liquid water oceans beneath the icy surface. The oceans are warmed by tidal interactions with the planet they orbit (in this case Jupiter).

If it is warm enough for liquid water then it is potentially warm enough for life.

[TheMolePatrol]

Waspie_Dwarf, on 18 February 2013 - 03:57 PM, said:

If it is warm enough for liquid water then it is potentially warm enough for life.

Yes, and another part of what fuels this idea is how they've found life on Earth in extreme conditions (ie. near volcanoes or deep under the ice). Also I've always wondered if there'd have to be liquid water between the ice and the core... just cause of the "goldilocks" effect between surface and core. Fun to think about.

[keithisco]

I just think that spreading out the available funding to disparate projects will leave as many questions as those that they are hoped to answer.

Mars most certainly, seems to have water and liquid water at the surface during certain seasons (there are plenty of images to suggest water flowing at certain times of the year), and with the possible discovery of Clays and sediments, surely this is a more achievable target?

I know that Arthur C. Clark proposed Europa as a source of life, but it was just a work of Science Fiction, and the "life" he promulgated was not exactly "sentient" . I do not expect to find any sentient life in the Solar System, so we have to concentrate Fiscal Imperitives on accessibility to the environments, within a time - scale that can maintain popular momentum (sorry, but you need peoples backing on these explorations). Mars should continue to be Our focus. Send probes to the poles to bore through the Ice, go to Olympus Mons (rich in all minerals), go into the Great Rift Valley where Mars' atmosphere is more heavily concentrated (still minute compared to the Atmospheric Pressure of the Earth). Just make a concentrated effort, internationally to thoroughly explore one of the planets... Just IMO

[DONTEATUS]

@ wimfloppp, Have you seen the Life and know how Cold it is at the Bottom of our ocean?

[Waspie_Dwarf]

DONTEATUS, on 18 February 2013 - 08:41 PM, said:

@ wimfloppp, Have you seen the Life and know how Cold it is at the Bottom of our ocean?

I'm not sure what point you are trying to make here DONTEATUS.

Deep ocean water is usually between 0 & 3°C. That is far warmer than the average surface temperature of even Mars (in fact it about the current temperature of my back garden).

Europa has a surface temperature which varies between -160°C at the equator and -220°C at the poles, and so without the heat generated by tidal flexing, wimfloppp would be right, it would be too cold for life.

[MedicTJ]

Why can't they do a Cassini-type mission and send a probe down to the surface?  I understand it would be more difficult because Europa doesn't have an atmosphere to slow down with...such as was the case with the Huygens probe and Titan.

But I wonder how they plan to look for signs of life through all that ice.  We're talking an ice cover that is estimated at 60 miles thick.

I'm all for the mission.  Europa is my favorite of all of the Jovian moons.  I just wish they'd do more I guess.

[Waspie_Dwarf]

MedicTJ, on 18 February 2013 - 10:14 PM, said:

Why can't they do a Cassini-type mission and send a probe down to the surface?  I understand it would be more difficult because Europa doesn't have an atmosphere to slow down with...such as was the case with the Huygens probe and Titan.

I'm not sure how much you could learn from the surface. It's rather smooth and featureless, which means it is a relatively new surface. Sure, you could do some chemical analysis of the surface ice, but would the scientific returns be worth the complexity, risk and expense of a lander?

An orbiter would probably give greater scientific return for less risk. An orbiter would be able to map the entire surface for example. Monitoring the orbit of the vehicle would lead to a better understanding of the internal make up of the planet.

MedicTJ, on 18 February 2013 - 10:14 PM, said:

But I wonder how they plan to look for signs of life through all that ice.  We're talking an ice cover that is estimated at 60 miles thick.

Searching for signs of life is a bit of journalistic sensationalism. The official NASA/JPL page for this mission makes no mention of such an objective (HERE).

Your figure of 60 miles deep is the figure for the water layer on Europa, including the ice and the liquid ocean. The depth of the ice crust isn't known and the Europa Clipper would carry a radar to try and determine that. If the crust is relatively thin then future missions might be able to melt their way through the ice to the ocean beneath.

MedicTJ, on 18 February 2013 - 10:14 PM, said:

I'm all for the mission.  Europa is my favorite of all of the Jovian moons.  I just wish they'd do more I guess.

I'm with you on this, although it all depends on the US government and the funds they allocate of course.

[Major Payne]

Nasa have wanted to visit Europa ever since Voyager first noticed that there were other "active" bodies in our Solar System (they noticed Pele erupting on Io). Before this they believed all other planets and moons were inactive. The series "The Planets" made in 1999 talks about sending a probe to Europa but the costs and more importantly how they get through the ice with the probe was still beyond their engineers at the time.
If they send a probe it will have to land then have some way of getting through the ice (example : drill or heat) then once through the ice it would have to survive immersed in water. Nasa would probably want to be able to search around so a propulsion system will be needed and a light source so we could see and maybe a chemical chamber for sampling. Every mission with Robotic rovers is absolutly amazing to see how they have acheived each one. This mission would be (I'm not sure what tops amazing) the ultimate in engineering and computing if it was to go ahead. I just hope I'm still around to witness this feat !!

[skookum]

Until we can devise away of getting through the ice I really cannot see the point of just looking at a frozen surface.  Hardly sounds like the most exciting missions.

[Waspie_Dwarf]

skookum, on 19 February 2013 - 07:42 AM, said:

Until we can devise away of getting through the ice I really cannot see the point of just looking at a frozen surface.  Hardly sounds like the most exciting missions.

So you would attempt to get through the ice without finding out how thick it is first? Or confirming the existence of the liquid ocean beneath? Or locating the best place to attempt to get through the ice?

[keithisco]

How about sending a relatively (!!) cheap sonar - acoustic arrays to impact the Ice, the acoustic cannon can be deployed over various frequencies, with the Sonar collecting the reflected signals and sending them back to Earth. This is already widely used in the Petro-Gas industries when prospecting for new Oil and Gas. The boundaries between layers are very distinct, would tell you how deep the ice is and also the depth of any liquid water below it.

It is a very well understood practise here on earth, and may de-risk any nascent technologies that may be "nice - to - have".

Just an idea...

[Waspie_Dwarf]

keithisco, on 19 February 2013 - 12:31 PM, said:

It is a very well understood practise here on earth, and may de-risk any nascent technologies that may be "nice - to - have".

Just an idea...

If I understand your idea it would still require a lander, which would be expensive, complicated and risky. As MedicTJ pointed out Europa has no appreciable atmosphere and so we would need a landing system that would make Curiosity's "seven minutes of terror" look like child's play. The price tag is $2 billion for an orbiter, I suspect a lander would be considerably more expensive.

We have to learn to walk before we can run. The Europa Clipper will provide us with a detailed map of the surface of Europa and its radar may help determine the best place for future missions to land.

NASA has always done its robotic exploration in a logical and systematic way, first flybys, then orbiters and then landers. This is how they have explored the Moon and Mars. Each phase builds on the knowledge of the last. Risk is reduced and scientific returns maximised. It seems sensible to explore Europa in the same way.