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Thread: What's NASA Up To And Other Space Stuff

  1. #1
    That's no moon. EyeKhan's Avatar
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    Default What's NASA Up To And Other Space Stuff




    Huge ocean confirmed underneath solar system's largest moon

    The solar system’s largest moon, Ganymede, in orbit around Jupiter, harbors an underground ocean containing more water than all the oceans on Earth. Scientists were already fairly confident in the ocean’s existence, based on the moon’s smooth icy surface—evidence of past resurfacing by the ocean—and other observations by the Galileo spacecraft, which made a handful of flybys in the 1990s. But new observations by the Hubble Space Telescope, published online today in the Journal of Geophysical Research: Space Physics, remove any remaining doubt. Ganymede now joins Jupiter’s Europa and two moons of Saturn, Titan and Enceladus, as moons with subsurface oceans—and good places to look for life. Ceres, the largest object in the asteroid belt, may also have a subsurface ocean. The new results come from Hubble’s observations of Ganymede’s magnetic field, which produces two auroral belts (pictured) that can be detected in the ultraviolet. Because of interactions with Jupiter’s own magnetic field, these belts rock back and forth. However, there is a third magnetic field in the mix—one emanating from the electrically conductive, saltwater ocean and induced by Jupiter’s field—that counterbalances Jupiter’s field and reduces the rocking of the auroral belts. The Hubble study suggests that the ocean can be no deeper than 330 kilometers below the surface.
    http://news.sciencemag.org/space/201...s-largest-moon

    Questions of living things aside, a big warm ocean has got to offer advantages for colonization. Resources, energy production, radiation shielding... Probably not easy access to metals, though. Depends on what's dissolved in that ocean, I guess.
    Last edited by EyeKhan; 03-26-2015 at 03:43 PM.
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    Unencrypted Wraith's Avatar
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    What's the benefit to colonizing it, though? Beyond the eggs in a basket thing. It seems like any long-term colony would have to be under the ice surface, which means it's not going to be easy access to space. Any elevator through the ice would require constant maintenance. I suppose there should be good access to tidal energy due to Jupiter, and life support will probably be easy enough except for the the pressure. Expansion will be pretty difficult, though, and I can't see any industrial benefits - most raw materials will probably be pretty hard to come by.

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    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by Wraith View Post
    What's the benefit to colonizing it, though? Beyond the eggs in a basket thing. It seems like any long-term colony would have to be under the ice surface, which means it's not going to be easy access to space. Any elevator through the ice would require constant maintenance. I suppose there should be good access to tidal energy due to Jupiter, and life support will probably be easy enough except for the the pressure. Expansion will be pretty difficult, though, and I can't see any industrial benefits - most raw materials will probably be pretty hard to come by.
    It all starts with why do it. The only answer we have today is A to make humanity/ your nation safer or B to make money. (I wonder if our culture limits the answers we can consider?) B is why the Europeans started their colonies, right? Others came later seeking freedom and/or independence, but colonial infrastructure was already begun. Why colonise Ganymede? I can't imagine making money doing it - and there are way cheaper/ better ways to safeguard the future of nations and the species....

    As for energy, since the ocean is liquid and there is no atmosphere, just drill a hole and vent some of the liquid water through a turbine to make electricity. That would be (relatively) simple. Mining would be tough - the rocky ocean bottom would likely have lots of goodies but getting to it would be at least as tough as mining the ocean bottom on Earth, ie tough enough we haven't bothered to try it. Might be able to access dissolved minerals in the water...
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    Unencrypted Wraith's Avatar
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    As for energy, since the ocean is liquid and there is no atmosphere, just drill a hole
    It would freeze shut again. Any hole you make is going to require constant maintenance & energy expenditure to stay open.

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    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by Wraith View Post
    It would freeze shut again. Any hole you make is going to require constant maintenance & energy expenditure to stay open.
    A smooth bore hole say with a steel liner, the pressure differential would probably keep it open. Ongoing geysers are apparently fairly common - see Enceladus, something's keeping multiple geysers open there, has to be the internal pressure. I would think the trick would be keeping it under control once it's open, like an oil well at the bottom of the Gulf of Mexico... In any case, any machinery or complex structure you build, especially the sort involved in a space colony, is going to require constant maintenance. Entropy, man.
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    Unencrypted Wraith's Avatar
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    Quote Originally Posted by EyeKhan View Post
    A smooth bore hole say with a steel liner, the pressure differential would probably keep it open. Ongoing geysers are apparently fairly common - see Enceladus, something's keeping multiple geysers open there, has to be the internal pressure. I would think the trick would be keeping it under control once it's open, like an oil well at the bottom of the Gulf of Mexico... In any case, any machinery or complex structure you build, especially the sort involved in a space colony, is going to require constant maintenance. Entropy, man.
    Enceladus has much more tidal heating than Ganymede does because of it's eccentric orbit. A steel liner won't stop ice from building up inside of it, even assuming you can find a place where the ice is motionless enough not to rip it apart.

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    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by Wraith View Post
    Enceladus has much more tidal heating than Ganymede does because of it's eccentric orbit. A steel liner won't stop ice from building up inside of it, even assuming you can find a place where the ice is motionless enough not to rip it apart.
    While acknowledging we're both completely talking out of our ass, do you really think the ice crust is moving around that much? Yeah, the surfaces of these moons are 'young,' by crater counts, but not that young. Are you assuming it's flowing like a glacier on Earth? Lacking any information to point one way or the other, my starting assumption was the crust would be relatively stable, like the crust of Earth. If not, that would be a show stopper for sure.

    But as for heating the tube, whatever it's made of, the energy to do it would be just a fraction of what a controlled geyser would generate. I think the engineering to keep it open isn't complicated so long as the crust is relatively stable. Consider that venting the water is also venting the interior heat. Again, I think the biggest issue would be keeping it under control - it might even expand, cause a crack, etc.

    Interesting side note, have you seen the pics of Ceres? There's some talk there could be a liquid layer there too, which sort of upends the tidal heating explanation for the big planet moons. What in the world would be heating the interior of Ceres, given it's size??? Assumptions have been that internal heat like that within Earth is driven by radioactive decay and that smaller bodies should be cooled by now. Ceres is really small.
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    Resiste et Mords! Steely Glint's Avatar
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    Colonizing any of the rocky bodies in the solar system has the problem that all of them have far lower gravity to that of earth, which has implications for the health and comfort of long-term inhabitants.

    A more realistic model is to put a habitat in orbit around any body which has some kind of economic purpose, which can be spun to produce a comfortable 1g.

    Then people can travel down to the surface to harvest the resources, or do so remotely. The orbital station is a more convenient platform for trade with Earth or other habitats. The resources could be stored on the planet itself if space is limited in orbit, and then only shipped up to orbit when a ship has docked ready to take the goods elsewhere. If there is some reason that processing the raw materials is better in low gravity, then the habitat might be larger and have facilities for doing that or it may be shipped to another habitat which specializes in such activities (say, over mars which is closer to earth and might have massive complexes of farms on the surface to support city-scale population living in orbit) before ultimately being taken on to Earth where it is ultimately turned into Useful Stuff. Earth in turn would supply these habitats with manufactured goods both practical and luxury as well as trained personnel and other benefits of it's vast population and long established infrastructure.

    Eventually, habitats would start trading directly with each other too. And thus Mankind will Conquer Space.
    To ends unknown, by means unworthy, to answer wishes long dead and gone
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    Quote Originally Posted by Steely Glint View Post
    Colonizing any of the rocky bodies in the solar system has the problem that all of them have far lower gravity to that of earth, which has implications for the health and comfort of long-term inhabitants.

    A more realistic model is to put a habitat in orbit around any body which has some kind of economic purpose, which can be spun to produce a comfortable 1g.

    Then people can travel down to the surface to harvest the resources, or do so remotely. The orbital station is a more convenient platform for trade with Earth or other habitats. The resources could be stored on the planet itself if space is limited in orbit, and then only shipped up to orbit when a ship has docked ready to take the goods elsewhere. If there is some reason that processing the raw materials is better in low gravity, then the habitat might be larger and have facilities for doing that or it may be shipped to another habitat which specializes in such activities (say, over mars which is closer to earth and might have massive complexes of farms on the surface to support city-scale population living in orbit) before ultimately being taken on to Earth where it is ultimately turned into Useful Stuff. Earth in turn would supply these habitats with manufactured goods both practical and luxury as well as trained personnel and other benefits of it's vast population and long established infrastructure.

    Eventually, habitats would start trading directly with each other too. And thus Mankind will Conquer Space.
    Was thinking smaller bodies like Ceres could be colonized with a rotating ring right around the damn thing, spun up for a 1 G or maybe a 3/4 G gravity. The icy body itself provides most of the resources the ring needs, the ring provides living/ commercial/ industrial infrastructure. Assuming a fusion energy source and the icy bodies are laden with organics (like comets), the whole oort cloud (millions of objects) could be colonized this way.

    Edit - the oort cloud objects would probably be easier even, given that the big planet moons have radiation and gravitational obstacles associated with their parent planets.
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    Senior Member Flixy's Avatar
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    Keep on keepin' the beat alive!

  11. #11
    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by Flixy View Post
    Well shit the bed.
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    Quote Originally Posted by EyeKhan View Post
    Well shit the bed.
    Are you surprised in the slightest? It was always clear to me they didn't have the resources to do this seriously.

    When Elon Musk tells me he wants to go to Mars, I believe him - he has a bajillion dollar company stuffed with engineers working on this problem right now. I still have my doubts about the viability of a real colony on Mars, but I think it's at least technically feasible to have a small, expensive, human presence on that planet, and that Musk (or NASA, or someone else with similar resources) can do it.

    Don't get me wrong - I love reading KSR's Mars trilogy just as much as the next person. But there are deep flaws in his imagined future, given the supposed improvements in robotics, AI, nanotechnology, healthcare, materials science, propulsion systems, etc. that would be necessary to even consider developing a self-sustaining colony on Mars. And the cost is likely to be astronomical.

    It cost us about $100 billion to put men on the moon for a few days. It cost us a bit more to put a small, fragile structure in LEO that can support a few people at a time - when we supply them with fresh food and gases every few months. To set up something permanent on Mars, it would likely be an order of magnitude larger, and even then would be extremely limited in ambition. Absent some quantum shift in technology, these are always going to be expensive, complex, limited projects.

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    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by wiggin View Post
    Are you surprised in the slightest? It was always clear to me they didn't have the resources to do this seriously.
    I'm just surprised how ridiculous the reality is and disappointed the mainstream media hasn't exposed that reality.
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    Quote Originally Posted by EyeKhan View Post
    I'm just surprised how ridiculous the reality is and disappointed the mainstream media hasn't exposed that reality.
    Every article about that project I've read has a certain note of incredulity when discussing it. It's not exactly a high priority for the MSM, but I haven't seen them fawning over it like it's actually going to happen. Pretty much every article I've seen raises the two big questions, about funding and technology. They might not be doing a very thorough job of investigative journalism on the project, but that's because these are fluff pieces. No one takes them seriously.

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    Resiste et Mords! Steely Glint's Avatar
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    Even the most wildly optimistic outcome for that expedition would result in the colony dead within a generation at most. Which would have set back any space colonisation efforts back decades or centuries. Without a supply train to Earth and an actual reason to exist any space colony is just expensive and drawn out suicide.

    Motherfuckers could at least have tried for the moon.
    To ends unknown, by means unworthy, to answer wishes long dead and gone
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  16. #16
    Quote Originally Posted by Steely Glint View Post
    Motherfuckers could at least have tried for the moon.
    Ah, but then they might have hit London.

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    Quote Originally Posted by EyeKhan View Post
    Might be able to access dissolved minerals in the water...
    Or just catch those 500 foot sharks.


    Quote Originally Posted by EyeKhan View Post
    Well shit the bed.
    "Crap one word answers."

    Garbage in, garbage out.

  18. #18
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    Quote Originally Posted by Steely Glint View Post
    Motherfuckers could at least have tried for the moon.
    The only thing the moon has going for it is proximity. There's no carbon, the gravity is way too light, the nights last for 14 days, there's no water (unless that deep crater at the pole really does have ice), there's no hope of ever terraforming it.... Mars is a colony candidate because there's at least minimal potential.

    Really, the best thing we could do with Mars is hit it with Ganymede. After a million years or so of cooling there would be a warmer, heavier world with a big ass ocean and an atmosphere (albeit unbreathable...). Seed it with some choice organisms and biosphere here we come. Just have to figure a way to compensate for the lack of a global magnetic field is all. And hell, if you can move Ganymede, you can figure that out. But on the other hand, if you can move Ganymede, you probably don't need to use it for terraforming Mars, except on a whim or something.
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    Unencrypted Wraith's Avatar
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    If you can move around Ganymede, you really should just be making an orbital ring.

    Quote Originally Posted by EyeKhan View Post
    do you really think the ice crust is moving around that much?
    No idea! I admit that I can't keep my Jovian moons straight, but I know that on at least one of the moons the ice surface is believed to be shifting around at a fairly frantic pace due to Jupiter's gravity, and I don't know that this isn't the case on Ganymede. It's tidally locked and with a stable orbit, so it probably isn't too bad there, but even slow shifts are going to involve levels of energy that steel can't deal with.

    Interesting side note, have you seen the pics of Ceres? There's some talk there could be a liquid layer there too, which sort of upends the tidal heating explanation for the big planet moons.
    Tidal heating isn't a requirement for subsurface liquids. I can think of a bunch of possibilities that would allow Ceres a liquid subsurface ocean - it's closer to the sun, so it gets more energy from there, radioactive heating, an ocean of ammonia instead of water, etc. This is honestly the first I've heard of it having a liquid layer, though.

  20. #20
    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by Wraith View Post
    If you can move around Ganymede, you really should just be making an orbital ring.

    No idea! I admit that I can't keep my Jovian moons straight, but I know that on at least one of the moons the ice surface is believed to be shifting around at a fairly frantic pace due to Jupiter's gravity, and I don't know that this isn't the case on Ganymede. It's tidally locked and with a stable orbit, so it probably isn't too bad there, but even slow shifts are going to involve levels of energy that steel can't deal with.
    The OP pic shows a lot of craters, so thinking there can't be a huge amount of shifting....

    This is honestly the first I've heard of it having a liquid layer, though.
    It was just mentioned in passing in an article I read about the probe going into orbit, so don't quote me....
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    Unencrypted Wraith's Avatar
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    Quote Originally Posted by EyeKhan View Post
    The OP pic shows a lot of craters, so thinking there can't be a huge amount of shifting....
    The lighter spots? It might just be the resolution, but those don't look like craters to me. It's likely that they're damage from strikes, but we don't know age (a Jovian moon should be getting far more frequent strikes than the moon), and they look like the ice healed over them. Compare to this image of the moon:



    Look at the edges - you can clearly see that they're craters there. I don't see that in the Ganymede pic.

    I'm not really sure why I'm talking about this though; you're probably right and there isn't much shifting. I only see a handful of the fracture lines that usually indicate movement like that.

    edit: I'm taking it back! This is Ganymede:

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    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by Wraith View Post
    The lighter spots? It might just be the resolution, but those don't look like craters to me. It's likely that they're damage from strikes, but we don't know age (a Jovian moon should be getting far more frequent strikes than the moon), and they look like the ice healed over them. Compare to this image of the moon:



    Look at the edges - you can clearly see that they're craters there. I don't see that in the Ganymede pic.

    I'm not really sure why I'm talking about this though; you're probably right and there isn't much shifting. I only see a handful of the fracture lines that usually indicate movement like that.

    edit: I'm taking it back! This is Ganymede:
    Even recent craters on an icy world are not well defined since the ice melts and fills the hole. And the marks that remain are relatively few presumably because the surface shifts around. The question is what time scale of shifting are we talking about - do crater marks get erased within decades, millennia, or is it more like millions of years? On Earth craters on the continents can last a long time, depending on how arid the region is, but generally get filled relatively quickly. And erosion and geology here is stable enough to build cities and infrastructure of all kinds. Probably icy moons have something analogous to the plates of Earth's crust with some relatively stable regions in the plate centers and messy fault zones at the edges.

    Interesting in the Ganymede pic the obvious fracture/ stress lines are pitted with apparently well defined craters. I wonder if the smaller strikes don't cause the melting that the larger ones do.

    On a side note, I went to the big crater out in Arizona. Very commercialized - it's privately owned - but pretty neat. And it's not far from the Petrified Forest National Park, which is also pretty neat. In between is Winslow Arizona, notable (only) for the Eagle's lyric. There's a statue of whoever sang it (Glen Fry?) on the corner and the song plays on outdoor speakers all day.
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    Senior Member earthJoker's Avatar
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    Quote Originally Posted by Steely Glint View Post
    Motherfuckers could at least have tried for the moon.
    "Wer Visionen hat, sollte zum Arzt gehen." - Helmut Schmidt

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    That's no moon. EyeKhan's Avatar
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    What makes that comic even more absurd is that Earth is never going to send anyone to Mars. We fantasize about it but that's it. So to use the metaphor of the joke it's more like Earth is watching Mars porn instead of doing the Moon.
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    Senior Member GGT's Avatar
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    Since none of this directly affects you, why do you give a shit?

  26. #26
    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by GGT View Post
    Since none of this directly affects you, why do you give a shit?
    Who? And give a shit about what?


    * * * * * *


    In other news, NASA has changed plans with respect to the asteroid capture mission - article below. This updated mission:

    A. seems more reasonably scoped

    B. will test asteroid redirect techniques for those of us concerned about getting hit

    C. gets to use Orion for a longish term mission and Mars mission technology proofing... (as if)

    but...

    D. will NOT not test any proof-of-concept techniques for future asteroid mining...



    NASA opts for boulder-snatch concept in its asteroid redirect mission




    Email Eric


    By Eric Hand 25 March 2015 5:30 pm 5 Comments
    NASA has decided to pluck a small boulder off an asteroid and bring it back to the vicinity of Earth, rather than bag up an entire asteroid, agency officials in charge of the Asteroid Redirect Mission (ARM) announced today.


    The $1.25 billion mission, which is planned to launch in December 2020, would send a robotic spacecraft for a rendezvous with an asteroid in 2022. After touching down on the asteroid’s surface, the spacecraft would snatch a boulder several meters across. The spacecraft would then orbit the asteroid for up to 400 days, testing out an idea for defending Earth from a catastrophic asteroid impact: using the spacecraft’s own gravitational field to subtly alter the asteroid’s orbit. Next, the spacecraft would bring the snatched rock back to Earth’s vicinity in 2025. Finally, as part of preparations for a possible mission to Mars, astronauts would visit and examine the rock for some 25 days, using the planned Orion spacecraft to make the trip.


    The boulder-snatch concept is expected to cost $100 million more than the bagging concept, but it would be better for developing technologies that would have greater value for exploring Mars, explained Robert Lightfoot, NASA’s associate administrator, during a teleconference today. Moreover, he says, whereas a bagging mission might get only one chance to snare its target, a boulder-snatching spacecraft will have a chance to survey the asteroid ahead of time before picking a target, and it could make several attempts at grabbing a boulder. “I’m going to have multiple targets when I get there, is what it boils down to,” he says. “That was the better value, in my opinion, for what we’re trying to do.”


    The leading target for ARM now is a 0.45-kilometer-wide carbonaceous C-type asteroid called 2008 EV5, Lightfoot says. The two other candidates are asteroids called Bennu and Itokawa, and ongoing searches are expected to yield one or two more candidates each year leading up to mission launch.


    Scientists say that there is intrinsic interest in C-type asteroids, which have never been visited by a spacecraft. They are darker than many asteroids because of all the primitive carbonaceous material they hold. Some may contain hydrated minerals, or even water ice, says Tim Swindle, director of the University of Arizona’s Lunar and Planetary Laboratory in Tucson. “They definitely have the potential of being a dirtier version of a comet.”


    But scientists have been skeptical about the mission, mostly because of concerns that its costs could end up threatening science missions, even though ARM is primarily designed to demonstrate capabilities for NASA’s human spaceflight program. Already, two science missions are planning on visiting a C-type asteroid. In December 2014, Japan’s space agency launched Hayabusa 2, which aims to return a few grams of asteroidal material to Earth in 2020. And in 2016, NASA plans to launch OSIRIS-REx, which aims to return at least 60 grams of material by 2023. “A lot of the wariness was that [ARM] would be funded out of science, and that the science return after going to other carbonaceous asteroids would not be that great,” Swindle says. “Everyone is going to remain wary until the mission has flown and the cost hasn’t come out of science one way or another.”


    ARM has also drawn skepticism from lawmakers in Congress, who will make the ultimate decision on whether to fund it.
    @DW - Was just thinking, can you change the thread title to something more generic? I occasionally make space science related threads and thought maybe if there was a single catch-all topic, would be more efficient...
    Last edited by EyeKhan; 03-26-2015 at 03:44 PM.
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    That's no moon. EyeKhan's Avatar
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    More about Ganymede, Enceladus and Europa, specifically their potential for life in light of likely thermal vents at the ocean bottom. Interestingly Ganymede's size causes problems with pressure at depth, whereas Europa and Enceladus not so much. The water pressure would form a pressure-ice at the bottom and seal the vents off from liquid water, depriving the nutrients necessary for life.

    Probably pressure would make mining extremely difficult and render an unlikely colonization scenario even less viable on all three worlds....



    Icy-Moon Discoveries: What They Mean for Alien Life Search




    New discoveries about icy moons in the outer solar system have raised exciting possibilities for life beyond Earth.


    Earlier this month, researchers made two big announcements: Saturn's moon Enceladus likely harbors hot springs, and Jupiter's huge satellite Ganymede apparently possesses a subsurface ocean that may contain more water than all of Earth does.


    However, while the discovery makes Enceladus, which also has a subsurface ocean, even more intriguing to astrobiologists, Ganymede is still not a great bet for alien life, researchers say. [6 Most Likely Places for Alien Life in the Solar System]


    Enceladus is the sixth-largest of Saturn's moons, with a diameter of only about 314 miles (505 kilometers). Despite its tiny size, Enceladus has drawn a great deal of attention due to its erupting water geysers, first seen by NASA's Cassini spacecraft in 2005. Now, scientists have found that Enceladus may have hot springs under its frozen crust. The discovery that the floor of its hidden ocean may be home to near-boiling temperatures is the first evidence of active hydrothermal vents beyond the oceans of Earth.


    "This surely has implications regarding astrobiology, life-searching and all those kinds of topics," said study author Hsiang-Wen Sean Hsu, a planetary scientist at the University of Colorado, Boulder.


    Specifically, these new findings suggest that the conditions on Enceladus' seafloor are similar to those found on Earth in a deep-sea field of hydrothermal vents known as Lost City in the Atlantic Ocean, which is home to a wide variety of animals, such as eels, snails, mussels, worms, shrimplike amphipods and flealike ostracods, said Gabriel Tobie, a planetologist at the University of Nantes in France.


    Lost City consists of 196-foot-tall (60 meters) limestone chimneys that release alkaline fluid that is low in metals and lower than boiling temperature. In contrast, most other known hydrothermal vents on Earth give off metal-rich acidic fluid that is hotter than boiling temperature.


    Alkaline hydrothermal vents might have been the birthplace of the first living organisms on the early Earth, supplying key nutrients and energy, Tobie said.


    "For Enceladus, the new discovery of hot vents enhances its chance for life," Tobie told Space.com.


    NASA also announced that a salty ocean hides beneath the icy crust of Ganymede, the largest moon in the solar system. Scientists using NASA's Hubble Space Telescope found that Ganymede's ocean could harbor more water than is found on Earth. Ganymede's sea may be about 60 miles (100 km) deep — 10 times the depth of Earth's oceans.


    However, this finding does not necessarily raise Ganymede's chances for life, Tobie said.


    "A major difference between Enceladus and Ganymede is the difference of pressure at the base of the ocean," Tobie said. The pressure at the base of Enceladus' ocean is rather low, at 50 to 100 bar — or about 50 to 100 times the atmospheric pressure of Earth at sea level. This low pressure permits water from circulating in underlying porous rocks, thus helping to drive chemical reactions that could lead life to emerge.


    In contrast, the pressure at the base of Ganymede's ocean is much higher — about 15,000 to 20,000 bar, Tobie said. Under such high pressure, not only is rock less porous, but water can form a kind of ice.


    "A very thick layer of high-pressure ice more than 400 kilometers [250 miles] thick will form at the base of the ocean," Tobie said. "Even if deep hot vents exist on Ganymede, the chance for life seems rather low due to the formation of this high-pressure ice layer."

    However, Ganymede is not the only watery moon of Jupiter. Prior research suggests that Europa, the fourth-largest moon of Jupiter, may possess both an ocean beneath its icy surface and hot springs.


    "Like in Enceladus, the ocean in Europa would be directly in contact with the rock core, which will favor water-rock interactions and exchange of nutrients with the ocean," Tobie said.


    "Both Europa and Enceladus have a high astrobiological potential," he added. "But for the moment, it is only a potential. Only future missions with in situ investigations will really answer if it is more than only a potential."

    http://www.space.com/28978-enceladus...adline+Feed%29
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  28. #28
    Unencrypted Wraith's Avatar
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    Quote Originally Posted by EyeKhan View Post
    @DW - Was just thinking, can you change the thread title to something more generic? I occasionally make space science related threads and thought maybe if there was a single catch-all topic, would be more efficient...
    Tell me what you want it changed to, if you can't change it yourself.

    edit: Nevermind, saw what you intended.

  29. #29
    Senior Member GGT's Avatar
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    Quote Originally Posted by EyeKhan View Post
    Who? And give a shit about what??
    In another thread, you said you didn't give a shit about policy if it didn't affect you directly. But here you are, going on about Space policies that don't directly affect you.

  30. #30
    That's no moon. EyeKhan's Avatar
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    Quote Originally Posted by GGT View Post
    In another thread, you said you didn't give a shit about policy if it didn't affect you directly. But here you are, going on about Space policies that don't directly affect you.
    I like space science a lot, so I have a give a shit factor. Though let us be clear, I don't give a shit enough to write my congressman about it or anything. And I'm not sure my general apathy = don't give a shit. More like = not something I can change, so not bothering with an effort.
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