New Evidence Points to Icy Plate Tectonics on Europa | Hacker News Reader

New Evidence Points to Icy Plate Tectonics on Europa

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78 pointsrbanffy39 comments

Europa Report is a great sci-fi movie. Some people don't like its low-budgetness, but it's very much worth checking out.

http://www.imdb.com/title/tt2051879/

I always get bad feelings when I see avoidable casualties on a space mission. Without giving too many spoilers, it's very unlikely a small nudge with manoeuvring thrusters wouldn't do the trick.

Space is unforgiving, but one thing you usually don't lack is time.

Also, any crew that feels they didn't train for all possible events in the mission feels too unbelievable. The guy in Prometheus that takes off his helmet as soon as they figure out the atmosphere of an alien habitat is breathable... don't be that guy.

As a contrast with a crew that seems very credible, https://en.wikipedia.org/wiki/Space_Odyssey_(TV_series) is an awesome series.

I would have much preferred if the alien life had been positive and friendly. Why are all the movies these days about hostile aliens?

Arrival has non-hostile aliens.

BTW, if anyone liked Arrival, the older film Contact is really good as well.

There's another film "The Arrival" that's a year older than Contact.

That one feels like a failed series pilot.

Yeah, I liked these.

District 9, perhaps? It's not a non-violent movie, but it's not quite as simple as 'alien menace ru n!'

Good one too.

1. historically, aliens are not friendly. (Where "aliens" are foreign citizens)

2. conflict is more engaging for a movie

Maybe. I am just tired of it. At least give them some depth like they used to do in Star Trek.

fair enough

You can make the conflict be between the humans or based on a fundamental misunderstanding (like The Abyss)

That's another good movie.

I really wish we'd get off our asses and study Europa et al, but instead we're stuck building this stupid-ass rocket so that congress looks good for making jobs. Just how much evidence needs to be pile up before we take these lines of inquiry seriously?

We're on it: https://www.jpl.nasa.gov/missions/europa-clipper/

Instruments were selected early this year, and specific designs and instrument contractors are being chosen.

I dunno, the vague "2020's" timeline is depressing. If we directed even a fraction of the SLS budget into this it could probably launch in late 2018 or 2019.

No, 2018-2019 is not possible. The instruments are not built yet!

There's a limit to what money could do to accelerate. Engineers are doing trade studies literally right now - here's an informal progress report given in October to the Space Studies Board of the National Academies of Science: http://sites.nationalacademies.org/cs/groups/ssbsite/documen...

Hopefully that is reassuring that it's not just an academic exercise! Earliest launch date is listed there as 2022 (page 3).

These studies are needed to be sure that agreed-upon science objectives would be met by the instruments. Here is an old Europa STM (science traceability matrix) that lays out the measurement goals (https://solarsystem.nasa.gov/europa/docs/Clipper_Trace_Matri... - compare around page 16 of the above presentation). The current STM will be much more elaborate.

The trade studies and experiments now underway are directed at checking these off or saying why they are not attainable. In particular, note (pg. 14/15) the multi-pronged approach to assessing the moon. One of the pieces is the plumes that are emerging from the surface; how do you locate and sample from one of the plumes? Do you need some on-board software to find them? If so, what sensors does it need?

Well hey, good luck! I withdraw my concerns (but maintain that SLS sucks).

All interest in solar system exploration is welcome!

Neat, thanks for the info! Do you know anything about the possibilities of an orbiter or lander on Europa given the radiation hazards?

The current nominal trajectory is on pages 6/7 of the first PDF I linked. It appears to be making ~40 near overpasses of the moon in the prime mission, some within 25-50 km of the surface (red lines), which is really quite remarkable considering the distance from Earth, light-time delays, and complexity of the Jovian system.

I would conjecture that our gravimetric/orbital model of the Jovian system will be updated during initial orbits so that planning for the overpasses will be refined after arrival.

There has been discussion of putting a (hard) lander on the spacecraft, to drop into one of the plumes. Last I heard, there was Congressional interest in the idea, but for technical reasons, AFAIK, it is out-of-scope for Europa Clipper. I think it's in study for a successor mission.

It's generally better to not try to do everything with one mission, but to plan a campaign with various contingencies.

To actually give the stupid-ass rocket something to do, people in congress have proposed doing a Europa mission. Congressman Culberson is even pushing for the Europa Clipper mission to have a lander. Although it is a bit unusual in that funding for such a mission is contingent on the Europa probe being launched on the SLS rather than whatever rocket NASA engineers decide on.

Aside from that, Europa is quite a challenging environment. The terrain is expected to be very rugged and it is bathed in radiation. The radiation is so extreme, that any probe we can reasonably send is only expected to last about 20 days.

[0]http://spacenews.com/europa-lander-work-continues-despite-bu...

Inquiry: if we do find some form of life in Europa, what does that tell us about the probability of life existing in the universe? Does it necessarily increase the likelihood that life is actually highly common in the universe, and a very regular outgrowth of nature?

EDIT: Specifically just life in general, not necessarily "intelligent life"

It would increase the number of data points from one to two and depending on the nature of the life we would learn a lot about how life develops. Right now our sample size is a little small.

It depends.

If we find unique life unlike that of earth life, it means that life is probably common in the universe.

If we find life that is similar/shares a common ancestor to earth life it means that life is probably less common in the universe but panspermia is more common than we thought.

Isn't "intelligent life" just a function of time of "life"? I am reading the book "Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness" currently and the book makes the case that intelligence and/or consciousness has evolved separately in mammals (humans) and cephalopods.

The more I look at diversity and evolution of life on Earth, it seems like "intelligent life" as we know it is just a inevitable consequence of evolution, given enough time, perhaps.

Well adapted life is a consequence of evolution. Intelligence is not necessary to survive. I am not sure who the master of the planet is: us or ants? Both are incredibly successful but with totally different strategies.

> Intelligence is not necessary to survive

It's even debatable whether it is an asset.

In fact, it can be argued that intelligence leads to low birth rates and population decline that extrapolates to eventual extinction.

Or it leads to avoiding overpopulation and depletion of resources. I think the intelligent thing for us to do would be to limit ourselves to a certain population size and stop growing.

It would be lovely, but this hypothesis is not confirmed by our observation.

Ssems we are not as intelligent as we think :-)

Either that, or intelligence is overrated.

Intelligence is overrated because non-intelligence lacked the faculties for contributing any offsetting negative ratings.

"Intelligent life" as we know it requires multi-cellular heterotrophic organisms. That depends on an abundance of resources (energy et al) able to give rise not merely to life but to a robust ecosystem. Without enough ecological niches there aren't enough ways for life to diversify significantly. Without enough energy and other resources you won't have either the generation cycle time or the carrying capacity to enable evolution of "advanced" multi-cellular life. There are environments on Earth that support life but could not support the development of intelligent life, they just lack the resources to do so. That might be true for some environments throughout the Universe as well. There might be places where some life can survive but is constrained from advancing beyond simple single cellular organisms due to lack of resources.

If we do find life there, it’s only a few assumptions away to find the great filter is ahead of us

What is a realistic timeframe when mankind will set foot on Europa (if ever). 2200? Is there any way to predict? I’d love to visit, ain’t gonna happen I guess :/

>> Excitingly, this same process could be delivering important minerals to the ocean below, heightening the moon’s status a potentially habitable world.

Ok, so the surface ice is being pulled down. But that means that there should be a correspondingly steady flow of deep water onto the surface. If that water is full of life then we should be able to see evidence of it in the surface ice. I'm not looking for frozen giant squid on the surface, but shouldn't we see some chemical evidence?

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