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NASA Teleconference About Europa
NASA will host a teleconference at 2 p.m. EDT Monday, Sept. 26, to present new findings from images captured by the agency's Hubble Space Telescope of Jupiter's icy moon, Europa.
Astronomers will present results from a unique Europa observing campaign that resulted in surprising evidence of activity that may be related to the presence of a subsurface ocean on Europa.
NASA currently plans to perform additional flybys of Europa and put a lander on the surface as part of the Europa Clipper mission. The ESA's Jupiter Icy Moon Explorer will also fly by Europa twice, but focus on Ganymede.
Nasa to Reveal 'Surprising' Activity On Jupiter's Moon Europa
There's something going on beneath the surface of Jupiter's icy moon Europa. But what?
NASA teased a "surprising" announcement for Monday, based on Hubble Space Telescope images of the celestial body, which many experts believe could contain a subsurface ocean, even possibly some form of life.
The US space agency has already proclaimed that Europa has "strong evidence for an ocean of liquid water beneath its crust and which could host conditions favorable for life."
At Monday's announcement, "astronomers will present results from a unique Europa observing campaign that resulted in surprising evidence of activity that may be related to the presence of a subsurface ocean," it said in a statement.
The announcement will be made at a news conference at 2 pm (1800 GMT) Monday featuring Paul Hertz, NASA's director of astrophysics, and William Sparks, an astronomer with the Space Telescope Science Institute in Baltimore.
(Score: 3, Insightful) by bradley13 on Monday September 26 2016, @01:13PM
I imagine some intelligence out there, wondering how life could possibly evolve under the constraints of a gravity well. You would be squashed to the surface of some rock, hardly able to move, except maybe with the support of liquid or gas. It just doesn't make sense to suppose that anything complex could evolve under such constraints...
Point is: We seem to always assume water = life, we look for planets in goldilocks zones, of roughly the same size as Earth, because that's what we know. Sure, maybe there's life on Europa. Meanwhile, what other possibilities have we failed to imagine?
Everyone is somebody else's weirdo.
(Score: 3, Interesting) by takyon on Monday September 26 2016, @01:40PM
https://soylentnews.org/comments.pl?sid=15060&cid=389581#commentwrap [soylentnews.org]
Life could probably find a way in 2g-2.5g conditions, and that could mean a wide range of planets have a mass suitable for life (say, 0.5-8 Earth masses). Once a planet becomes a mini-Neptune (10 Earth masses?), that's where the trouble might start. Also, the boundary between giant rocky planet and mini gas giant might be a little flexible and based on protoplanetary conditions.
The amount of water could be interesting as well. Some exoplanets are covered in miles of liquid water, with no land. Life might be able to form in that condition, but good luck advancing to building printing presses, radio towers and spaceships if there is no dry land (an icy region floating on the water doesn't count - there would be no trees or iron/stone/uranium/etc. there).
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by Phoenix666 on Monday September 26 2016, @02:29PM
We know that to be true on Earth, but does that preclude the development of technology in an aqueous environment? I'm not so sure. On Earth, aquatic species grow intricate structures (sponges, coral). There are also aquatic species that are quite intelligent (whales, dolphins, octopi). There's also the observation that creatures tend to use what's available; TIMTOWTDI. It would be extraordinary to discover intelligent sub-aquatic life that harnesses an organic technology whereby they direct other species to construct their tools and structures for them, using the minerals in solution.
Washington DC delenda est.
(Score: 4, Interesting) by VLM on Monday September 26 2016, @07:51PM
Life could probably find a way in 2g-2.5g conditions
Angle of repose is mostly independent of gravity so the landscape would look more or less similar.
However potential energy will not be denied and the impact damage of falling in 2G will be much worse than falling in 1G it would scale with the square of acceleration.
That will have two interesting life features, one is rivers will gouge the earth more violently making a more treacherous landscape and the other is large bipedalism is not likely a survivable thing, long term. Maybe something human sized could evolve but it would be the local equivalent of megafauna, biggest thing on the plains. Likely that means has to be herbivore which means it'll be pretty dumb.
Going the other direction the earth is pretty marginal for long term water at 1G and much less you end up with mars, normal ionization and dissociation in the upper atmosphere combined with low escape velocity for hydrogen in lower G means all your water blows away in a 100 million years or whatever.
There are other problems with solar cycles and geology and gravity where you can't just cheat and say "OK evolution happens 10x slower" because due to solar growth cycle we only have a couple hundred milliion years plus or minus the usual snowball earth episodes before the sun makes life untenable here, and 10x slower rate would mean the alpha predator over the entire life of the planet would only be a trilobite or maybe only a protist of some type.
So using known biochemistry anything smaller than 1G implies a desert planet "dune" without much life, and anything larger than 1G implies ever smaller herbivore megafauna leading to smaller (dumber) carnivore/omnivore life. 1G seems to lead to life where a tiny fraction wonders about the effect of 1G so if we're not a lucky local maxima we're at least close to it.
(Score: 0) by Anonymous Coward on Tuesday September 27 2016, @02:04AM
Potential energy goes as g not g^2. Likewise, impact velocity goes as sqrt(g).
(Score: 0) by Anonymous Coward on Monday September 26 2016, @01:51PM
The more we discover the more things we consider. Before Europa no one theorized that life could exist on a moon or outside the goldilocks zone. There are even ideas out there that life, very different from our own, could exist on places like Titan where the liquid and weather on the surface is not water but hydrocarbons. As we learn more ideas evolve. That's the excitement of science.
(Score: 0) by Anonymous Coward on Monday September 26 2016, @02:18PM
There are more geniuses on other planets than there are people on Earth.
(Score: 3, Funny) by theluggage on Monday September 26 2016, @02:35PM
Meanwhile, what other possibilities have we failed to imagine?
Science Fiction is chock full of silicon-based life forms, sentient stars & planets, intelligent dust clouds, giant space amoebas, self-aware systems of convection cells in an ocean and super-intelligent shades of the colour blue - I don't think the human race can be accused of lack of imagination.
However, what we do lack is any clue of what signs to look for that might indicate, say, creatures living in the quantum foam or comets with neurones formed from exotic phases of cometary ice (hopefully, they'll find a way of texting us before sending an armada to avenge the victims of the weapon of mass destruction known as 'I Love Lucy' whose resonances cause degrebulization of the zagbards in juvenile Grobogulans - but then if we can't be bother to read the notice written plain as day in the modulation of the Hubble constant, maybe we just deserve to be stomped...)
Now, with ugly bags of mostly water like us, however, we know the signs: liquid water, abnormal oxygen levels, methane, complex organic molecules, discarded fast food wrappers and fucked-over ecosystems...
(Score: 0) by Anonymous Coward on Monday September 26 2016, @07:21PM
Point is: We seem to always assume water = life, we look for planets in goldilocks zones, of roughly the same size as Earth, because that's what we know. Sure, maybe there's life on Europa. Meanwhile, what other possibilities have we failed to imagine?
What do you propose we do to locate things we don't even know we don't know?
Of course we are still doing basic science to search around for basic knowledge (among other things, see the recent large number of planets outside our solar system which have been discovered in the past 10 years). In the meantime, though, what should we do? Say "hey, this planet has water, let's not bother investigating it because water was essential to life on Earth and that's all old-hat by now. We want something NEW!"
(Score: 2) by GreatAuntAnesthesia on Tuesday September 27 2016, @09:54AM
To a certain extent what you say is true, but unless the laws of physics and chemistry are somehow radically different in other parts of the universe (and we're pretty damned sure they aren't), then actually we can make quite a few good assumptions that put boundaries on the likely places to find life:
1 - Life is basically an exercise in chemistry [1] which means that you need a stable-ish environment where chemistry can occur. That means the surface of stars, the hearts of black holes and the depths of gas giants are out of the question. They are too hot, too intense for atoms to bond together and then unbond later in useful and interesting ways.[2] Similarly ridiculously cold places are unlikely to harbour life, since chemistry can't happen without energy.[3]
2 - More specifically, life is about chemistry which enables the capture, storage and release of energy in a controlled and repeatable way. That is a requirement for growing, feeding, reproducing etc. You can't call something "alive" if it doesn't do anything more interesting than sit still and slowly decay / erode / rust / maybe grow some pretty crystals. Things that behave that way are called "rocks" and if they are alive then PETA are going to get even weirder. Anyway, some elements are better for working with energy than others. Carbon is more useful than silicon, for instance. Silicon is more useful than, say, iron. That's one of the reasons SETIists are always banging on about water and oxygen and carbon - they're very well suited to the kind of dynamic chemistry that enables energy management.
3 - Furthermore chemistry needs chemicals (obviously) and evolution can only work with what's available. It's all very well hypothesising an alien that eats plutonium and craps out skittles but that life form isn't ever going to evolve because there just aren't significant naturally occurring deposits of plutonium anywhere in the universe. Water, on the other hand, is abundant, probably one of the most common things in the universe (after nothingness, helium and loose hydrogen.) Carbon too is pretty commonplace compared to most other elements.
4 - Which leads us to the point of the post; gravity wells. For chemistry to occur you need all these things (useful elements, stable-ish environment) all together in one place. That doesn't happen out in deep space. Even what we think of as "clouds" in space, the colourful[4] star nurseries and spectacular nebulae you see in hubble photos are still incredibly sparse, desolate volumes of slightly-less-close-to-vacuum-than-usual bugger all.[5] The only thing capable of bringing elements together is... gravity. I guess you could argue that life might arise on some negligible-gravity asteroid or comet or something but then we are back to (1) the stable-ish environment. Planetary atmospheres (and oceans) are great for smoothing out the extremes of hot and cold found in space, and also for stirring and mixing all those chemicals together to enable the chemistry to happen.
[1] Unless you want to go completely Star Trek and start talking about "energy-based life forms" and such which, well, you might as well be talking about the FSM.
[2] I think some people (science fiction authors, at least) have suggested that there may be some kind of "chemistry" going on in the most super-intense hot environments, where atoms break down and you just have a soup of subatomic particles whose interactions in those conditions we don't yet fully understand. That would fall under "...laws of chemistry work differently in other parts of the universe" as stated in the first paragraph.
[3] Technically what we are looking for is an energy gradient - IE a place where there are patches of higher energy and patches of lower energy and some way of exploiting the difference. This might be possible on extremely cold worlds, but at best you could expect any life to be ridiculously slow-moving: As in, "a seed takes a hundred thousands years to grow a leaf" kind of slow.
[4] False colour, remember. In "true colour" those images would be just white specks on a black background, same as any other patch of sky.
[5] I guess it might also be worth considering the proto-stellar disc just before a star ignites. Thick(ish) soupy mixture of elements, parts of it would be of a sensible (and maybe stable?) temperature... who knows? Of course star ignition would be an extinction event.
Disclaimer: IANAPhysicist, Chemist or Xenowhateverist. Corrections from more educated people are more than welcome.
TL;DR: We look for life on goldilocks planets because Science.