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Saturn moon 'able to support life'

bbc.com

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Re: Saturn moon 'able to support life'

#221

Post by lmm »

yomly wrote: post #158

So here's an orthogonal question. In a field like space navigation, where your findings come back after an expedition planned 5-10+ years ago how do you be "agile"? What is the go to project management style? Can we learn from these disciplines for alternative practices to building software?

We can find alternative practices, sure. They'd likely be similar to early software development practices that were inspired by physical engineering practices.

But they're going to be less effective. The whole point of agile is to arrange your practices around the short feedback loops that are uniquely possible with software and get the most possible value out of them.

Re: Saturn moon 'able to support life'

#222

Post by platz »

pmalynin wrote: post #220
smdz wrote: post #210

Earlier quoted context omitted.

Critical thinking is good - but kids can ask questions that are very difficult to answer (but we think of those as common knowledge) For example: This question > Why is 1+0 = 1 and not 10 Attempt to find an answer will generate more questions and it is a journey down the rabbit hole. Sometimes you don't want to do that. And upto high-school I learnt things that were based on assumptions that I kept questioning. Inter…

Because zero is an additive identity. Might as well teach your kid number theory.

> rabbit hole

Re: Saturn moon 'able to support life'

#223

Post by logfromblammo »

adrianN wrote: post #101
usefulcat wrote: post #96

Earlier quoted context omitted.

But said maintenance is relatively recent (~100 years?) compared to their age.

I'd guess that the Egyptians maintained them. If I'm not mistaken they where in pretty good shape during Roman times.

Human activity weathers stone monuments faster than desert winds. If I recall correctly, the original sheathing stones and capstones of the pyramids were gradually stolen. The Sphinx was used for target practice.

Water, on the other hand, will tear through your stones much more quickly. In a wet, temperate climate, the weak acid falling from the sky will wear limestone. The moisture invading cracks and freezing will widen those cracks. Lichens will bore tiny holes into the rock, and plant roots will cause fissures to expand. Additionally, moisture that penetrates to metallic structural reinforcement will oxidize and swell that reinforcement to pop bits off of the stone (observable from earlier attempts at restoration at the Parthenon, where the replacement anchor pins weren't coated in lead correctly, and they started to crack the rock blocks--now they use non-corroding titanium pins). Sometimes mortar does not swell or expand at the same rate as whatever it binds, and something will crack, admit water, and generally deteriorate from there.

Water is the enemy of preservation. They pyramids didn't survive just because they are stone, but because they are also dry.

And on a long enough geological timescale, every potential building site will eventually experience every climate, including being entirely immersed in salt water.

Re: Saturn moon 'able to support life'

#224

Post by btouellette »

vkreso wrote: post #199
vidarh wrote: post #152

Earlier quoted context omitted.

They wouldn't need generation ships. You "just" need sufficient tech to put engines on a suitable astroid and accelerate it to a decent fraction of c; it only needs enough logic to fine tune the path. An invasion force is horribly inefficient vs. just slamming a lot of mass at someone at high enough speed. And it only takes one massively paranoid, xenophobic species lobbing big rocks at people to ruin the entire neig…

> They wouldn't need generation ships. You "just" need sufficient tech to put engines on a suitable astroid and accelerate it to a decent fraction of c; it only needs enough logic to fine tune the path. An invasion force is horribly inefficient vs. just slamming a lot of mass at someone at high enough speed. I misplaced a link and the name of an author of a sci-fi novel in which space battles are much more science ba…

The Remembrance of Earth's Past series by Liu Cixin? It also has the "lurker" theory of cosmic sociology being discussed in this thread.

Re: Saturn moon 'able to support life'

#225

Post by pmalynin »

platz wrote: post #222
pmalynin wrote: post #220

Earlier quoted context omitted.

Because zero is an additive identity. Might as well teach your kid number theory.

> rabbit hole

But why not go down a rabbit hole with a child, I feel it could be a wonderful experience that will challenge your beliefs and that of the kid. I don't really get the fascination with ignoring these type of questions: "Dad why is the sky blue" - "Eat your ice cream Timmy".

Re: Saturn moon 'able to support life'

#226

Post by funkyy »

Balgair wrote: post #213
smdz wrote: post #178

I always had this question - Can life exist outside our perception of biological life? Intelligent life might be an anomaly, and rare in the universe - but is it possible that life exists outside our perception of biology? Afterall everything is just rules and actions that lead to predictable reactions (unless quantum physics says something else) I look at artificial life - that exists in virtual environments. It loo…

Define: life ;)

Anything that goal is to look for the source of energy. This must be an actual goal and such a being must be oriented around this.

I think this would create a simple definition.

Re: Saturn moon 'able to support life'

#227

Post by lordelph »

Pyxl101 wrote: post #124
hyperpallium wrote: post #117

Earlier quoted context omitted.

Spiders also produce more pound per pound intelligence. They are solitary. What if they became social? Brain-body ratio is provocative, but not the whole story. Seeing galahs (Australian corvid https://wikipedia.org/wiki/Galah ) socialize in trees in monkey troop-like fashion, dextrous in tooth and claw, makes me believe they are on the way. Though maybe raccons are next. > efficiency is Good Enough I was thinking th…

Here's a crazy idea: What if we picked a domesticated animal such as a pig or dog, and began to breed the species for intelligence? Or any other suitable animal. Only intelligence (and general health), over an extended period. It's believed that all of the modern dog breeds came about in the last hundred or so years. Modern domesticated dogs are definitely intelligent, especially socially intelligent. They understand…

For a book which explores this, and similar ideas, try "Oryx and Crake" by Margaret Atwood.

Re: Saturn moon 'able to support life'

#228

Post by jhedwards »

smdz wrote: post #178

I always had this question - Can life exist outside our perception of biological life? Intelligent life might be an anomaly, and rare in the universe - but is it possible that life exists outside our perception of biology? Afterall everything is just rules and actions that lead to predictable reactions (unless quantum physics says something else) I look at artificial life - that exists in virtual environments. It loo…

If you enjoy pondering this question you should definitely check out the works of Stanislaw Lem. One of the main themes of his work is that alien life would be fundamentally different from life as we know it and that human consciousness, bound by the concepts that we use to understand our own world, would be unable to comprehend it. His novels contain a lot of imaginative examples of that kind of alien life, the most famous perhaps being the planet in Solaris.

Re: Saturn moon 'able to support life'

#229

Post by aperrien »

smdz wrote: post #210
nkrisc wrote: post #204

Earlier quoted context omitted.

Critical thinking is the greatest threat to religious indoctrination as it relies on the acceptance of teachings as fact from authorities at face-value without question. If a child learns to be skeptical and questioning, they'll never learn to believe something that can't be supported given the currently available evidence, or may very well be contradicted by it.

Critical thinking is good - but kids can ask questions that are very difficult to answer (but we think of those as common knowledge) For example: This question > Why is 1+0 = 1 and not 10 Attempt to find an answer will generate more questions and it is a journey down the rabbit hole. Sometimes you don't want to do that. And upto high-school I learnt things that were based on assumptions that I kept questioning. Inter…

You tell the child that that is a good, but complicated question, and it will take time to give them the full answer. Then you can introduce them to the pieces as they can understand them, and as you have time.

Re: Saturn moon 'able to support life'

#230

Post by platz »

pmalynin wrote: post #225
platz wrote: post #222

Earlier quoted context omitted.

> rabbit hole

But why not go down a rabbit hole with a child, I feel it could be a wonderful experience that will challenge your beliefs and that of the kid. I don't really get the fascination with ignoring these type of questions: "Dad why is the sky blue" - "Eat your ice cream Timmy".

because child has to get homework done to go to bed or because sibling spilled some milk and there is no time to teach number theory to toddler who is trying to understand 1 + 0
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