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Comment Does this mean more fuel for thrusters? (Score 2) 52

So if they aren't going to be using the main engine for a major trajectory shift, does this mean that more fuel is available for the thrusters?

In my long (non) professional career of following of various space programs, it always seems that the limiting factors to a mission is 1) the availability of fuel for the thrusters (for minor course corrections, attitude control/dumping of momentum) and 2) how many reaction wheels are still working (although there have been creative solutions such as using sunlight pressure for attitude control). If Juno's thrusters same the same fuel (and fuel tank!) as the main engine then perhaps it now has access to a much larger supply and can conceivably last a long long time. :)

Of course, Juno's limiting factor WAS the intense radiation it was going to have to have faced but perhaps the new orbit has reduced that substantially. In fact, if there IS a lot more fuel available, perhaps it can use the fuel (once the primary mission is over) to get it out of the high radiation regions (perhaps by some creative gravity assists from the Galilean moons) and perform a multi-year "tour" of the Jovian system. This would possibly make up for the scientific tragedy that befell the Galileo probe when its high gain antennae didn't open and the data rate dropped by (three? more?) orders of magnitude. It'd be fantastic to get some really good pictures of Europa (life!) and Io (volcanoes!).

Or just put it in a relatively distant parking orbit around Jupiter and (because it's solar powered) let it monitor the Jovian system for (hopefully) decades

Comment another fish in the sea (Score 1) 148

In a dozen lifetimes I could hardly scratch all the great content on the internet that's available for free, or with barely any strings attached.

The best defense against the dark arts of advertising is a curiosity streak that's a mile wide.

Two words: substitute good.

At the first sign of trouble, I open alternate tabs like a cowboy after a bar brawl.

Comment Re:Won't work everywhere, or really anywhere else (Score 1) 179

So you've replaced a single CEO with the results of a vote between a few "senior staff". That leaves the rest of the company "not in charge".

Why stop your argument there? With another sentence or two, we can rewind western civilization all the way back to the Taliban's conception of marriage.

Because in any human collective, only one party can ultimately wear the pants.

How the truth stings. Resistance is futile. Sauron does not share power. Those poor, deluded Swedes. Yada yada yada.

Comment Re:What does this mean, exactly? (Score 2) 211

Ultimately, this will affect almost no one. Planning for this change has been happening for a long time now. Your favorite add-ons will continue to work.

Trust, but keep one foot wedged in the emergency exit, and one ear cocked for a fell voice on the air:

I cannot continue working on my add-ons anymore. I'm sorry, but it's time.

It took me a year and a half of extensive rewriting to make my add-ons e10s/multiprocess compatible, something that is being rolled out only now, all with the prospect of a long-lasting life for them. And the WebExtensions announcement was made not two months after. "Demotivating" doesn't quite cover it ...

Comment Re:Ray Kurzweil (Score 1) 84

All kinds of foods are fortified with all kinds of vitamins

The fact that a particular tofu manufacturer may fortify their product with B12 is only because they know that a lot of their market is vegan. Not all vegans eat tofu, or will pay attention to whether their brand does or does not fortify. Not all eat cereal either (the main "multivitamin-fortified" food that people consume), and a serving of a typical fortified cereal only provides about a quarter of your RDA anyway. Lots of other foods are fortified by specific nutrients, but rarely B12.

Comment Re:Strange (Score 1) 184

A person who doesn't even understand the concept of splitting up paragraphs is in no grounds for criticizing someone else as being "unintelligible". Likewise, starting off a debate by accusing the other side of "psychosis"... well, I'll not comment about what that says about you.

. 1. Your understanding of why water is required for LAWKI is wrong. It's principle properties (as far as LAWKI is concerned) are thought to be A. hydrogen bonding and B. solvency.

1) The presence of water inside a cell does not require that a wet external environment was the source of the hydrogen in said water.

2) There are countless solvents in the universe. Out of sheer coincidence over the past two days I've been reading papers on the solvency properties of ionic liquids and carbon disulfide (the latter being common naturally). The studied possibilities of cyanide chemistry on Titan use methane as a solvent. Ammonia is also common in the universe and is an excellent solvent. (if you want to argue against methane and ammonia because they're not polar, you're going to have to defend the concept that solvents must be polar - which in the studied case for Titan, they absolutely don't have to be in order to create some spectacularly complex cyanide chemistry). Carbon dioxide is a superb solvent in its supercritical state. There are lots and lots of common natural compounds that are excellent solvents in widely varying environments. Not environments that LAWKI would survive in, but that's because LAWKI is evolved to the conditions of Earth, utilizing molecules that are stable on Earth conditions for its life processes.

2. The Drake Equation. I'd speculate that if you sat down and studied the equation *critically*, that you'd see it has major flaws, the most serious (imho) is the assumption that each of its terms can be reduced to numerical values and that each term is independent of the others.

Which can be resolved by combining terms. Feel free to present your alternative (many people have); each form nonetheless invariably projects massive numbers of civilizations.

3. The Fermi Paradox also has serious problems. Let's say that interstellar travel is technically impossible

A premise I'll gladly accept.

- that there's no propulsion technology which can transport viable (sufficiently complex) intelligent life across interstellar distances. Then there is no "paradox"

Except that there still is, because even if a civilization evolved only 1% earlier than ours did (a very tiny margin!), it's 138 million years old, and can thus be expected to have been long moving out at relativistic speeds in all directions. The Milky Way's diameter is only 100-180k light years. Even Andromeda is only 2,5 million light years away. Even civilizations having advanced to the point of interstellar travel just a mere 1% earlier than we've reached our current state should be arriving from all over the local group - let alone ones that developed 5%, 15%, 50%, etc earlier. The fact that life tends to spring up wherever there's water is not consistent with the observed emptiness of the universe.

Cosmological distances help keep is apart, but it is also a requirement that life be very rare.

Another problem can be seen if I use the same reasoning to claim that every square meter of the Earth's surface must have been "visited"

The more appropriate comparison, since we're talking about beings that reproduce, and over timescales representing countless generations, is to claim that every square meter of Earth's surface must have been visited by bacteria. And golly gee, it has. Even ignoring the point that bacteria don't have intelligence to guide them.

Finally, you should account for the stupidity of any group of fans of any meme. The *experts* (hopefully, the people who have enough of a background and have carefully thought about the problem of detecting extraterrestrial life, which would include careful and thorough study of the scientific literature) would, I believe, strongly disagree with your assertion that they claim water = life.

There is no broad agreement among scientists about the topic. So your trying to assert that "experts think X" is simply wrong, for whatever value of X you wish to choose. There are some scientists who are very keen on the concept of life being found wherever there's water, and just as many opposed.

LAWKI requires the presence of liquid water

More specifically, LAWKI has evolved to require the presence of liquid water. We know absolutely nothing about what form it was when it began.

Liquid water doesn't require the presence of life.

Tell that to the large numbers of scientists working at NASA who assert otherwise. They've even used "follow the water" as the official name of several campaigns' search for life on other planets. The "follow the water" concept is that wherever water has existed in the liquid state, life is likely to arise. This is a concept I am very much against.

There's so little we know about abiogenesis, that talking about it is practically useless

Exactly my point. Yet so many people - and I'm not entirely sure whether you're among them - keep acting as if LAWKI in its current state must inherently represent the same sort of biological processes as in its earliest state, with the same sort of needs. And the "follow the water" crowd further asserts that wherever water exists, life is likely to arise - as if we have any bloody clue about what conditions led to the first successful hypercycles on Earth.

I note that while I hold out some hope we will discover planets in our local neighborhood (say 500 light years from Earth) which have spectroscopic indications that life might exist, it is almost certain that there is no way for life to be detected at "cosmological" distances

I was very clearly and explicitly referring to other species engaging in interstellar travel. Something that's pretty much a given for any species that's been around even a fraction of a percent longer than we have. How you interpreted the term "encountering" as "detecting" is beyond me.

Another obvious "solution" to the Fermi Paradox, is that IF intelligence must evolve in social emotional animals, then it will inevitably produce a species which will cause it's own extinction

Extinction becomes difficult once you become a multiplanetary species, and almost impossible once you become an interstellar species. Some, some may well find a way to kill all of themselves before reaching that point (although total extinction is a tall order). But if you're in the "follow the water" crowd there should be life evolving at almost every star, often multiple planets per star. Unless you're talking a probability of extinction on the order of 99,99999999999999999999999%, that explanation doesn't cut it.

The assumption that intelligence is a benefit for the long-term survival (say on scales of hundreds of thousands to millions of years) has exactly zero evidence to support it. If it were such a great thing, it would probably already have developed *here* and we'd be covered in scales (or have 6 legs).

I can't even make out what you're trying to argue. Intelligence did evolve here. On many different lines (birds are quite intelligent, cephlapods, other mammals, etc).

If by intelligence you mean sentience, it did evolve here too. Are you trying to assert that it should have evolved instantly with the first life? Since when does evolution work that way?

Comment Re:Ray Kurzweil (Score 5, Interesting) 84

Funny, the only schizophrenic I've ever known was also vegan.

I'm a vegetarian, and have strong sympathy for the motives behind being vegan. But take your B-12, my vegan friends. Unless you eat large amounts of soil, feces, or bacterial concentrates, or you've had a rumen implanted in your body, you need it. Higher plants don't make it. Every "vegetarian" mammal has to get it from somewhere, and those not lucky enough to have rumens (or other organs filling equivalent "cultivate lots of bacteria" roles) either get it through eating soil, feces, insects (accidentally or on purpose), or other such sources. Even our "strict" vegetarian gorilla relatives eat grubs. Heck, even though I consume dairy, I still take a B-12 supplement, just to ensure that I get enough.

Also, B-12 shortage doesn't hit you immediately. The body stores about 5 years of B-12. So it'll catch up with you sooner or later.

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