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Comment Re:Real World? (Score 1) 120

It's a way of leaving Watney behind that seems maybe plausible if you don't think about it. That's the best I can say about it.

That's not a lot to say, really. I prefer my sf to engage my braincell a bit more than that. Well, I'll probably see it at some point, but I can't say that I'm motivated to actually go out of my way (e.g., to a city with a cinema, or to log onto the wife's DVD library website to book it) for it. I'll see if the copy of the book turns up on the recreation room's library. Frequently the book is considerably better thought out than the screen play. Different audiences.

In Earth's atmosphere, it is possible for wind to drive solid objects through others, but it typically takes a tornado.

A rather different situation. In one case, one object is stationary and the other is acquiring kinetic energy by being blown around in the wind for an indeterminate period of time. (Actually, there was another SF film a few years ago where the MacGuffin was a device for measuring some aspects of that movement.) In the other case, both objects start at zero velocity (with respect to the ground and each other) in the significantly slower wind at ground level.

I have no idea what sort of wind would be required for the Martian air to do that.

I don't have numbers to hand, but work has been done on this looking at dust devils (mini-tornados) on Mars, imaged by the very mapping satellites I mentioned earlier. There are also weather stations on all of the landers, of varying degrees of complexity. We may not have as good an understanding on Mars as we do on Earth, but our scientists and their robots are finding out this sort of thing.

I swap tweets from time with a guy whose signature line was "There is a robot on Mars. I give it instructions, and it does what I tell it to do." I like keeping up to speed on interplanetary exploration activity.

Comment Re:Real World? (Score 1) 120

Wait - hang on. The wind was sufficiently powerful to pick up an item of mean density 3 or 4 tonnes/ cubic metre. and "slam it into" something of mean density about 1+a-bit tonnes per cubic metre which wasn't moving. I don't know about you, but when I last got picked up by the wind, my ice axes (metal and GFRP ; they sink, I float) stayed laying on the ground because they were denser than me. (My rope also held, which is why I was using a rope.)

Oh, sorry, I'm forgetting that the "left behind on Mars" is a MacGuffin. Given that it's over a decade since we put the first (semi-)permanent mapping satellites into Martian orbit, such a storm sneaking up on a landed mission simply is not credible.

I only had four of my six impossible things before breakfast today. But I feel full, and don't think I can swallow that one.

Comment Re:Real World? (Score 1) 120

Yes, they knew where he was and couldn't (or wouldn't) do anything to help him. But they knew where he was. The big difficulty, particularly for people who are intending to help, is if you can't find someone who you think is missing, or if you think someone is missing, but don't know they are missing. Or in the cave rescue scenario, you know someone is in a cave somewhere within walking distance of here, but you have to thoroughly search every one (including the unexplored or un-published ones), when there is no way of knowing if you're within 2 feet of the missing person or party unless you're actually within the same cave system as them.

Everest isn't a good example of normal mountaineering because there are a lot of people who take their egos and business plans there, leading to some extremely distorted and aberrant behaviour. That it also makes headlines is unfortunate. It'd probably do a lot of good if the Nepalese government shut it down for a decade or two, or required people to have climbed all the other 8 thousanders before being allowed on Everest. That should weed out the money bags and incompetents.

Comment Re:It is "hctaw s'yelaP" argument. (Score 1) 41

Darwin was certainly aware of Paley and his interpretation of biological design, but it's also pretty clear that he didn't share Paley's interpretation. Darwin's own description of "Origin" as "one extended argument" is precisely challenging Paley's interpretation of the appearance of design as being the result (per Darwin) of descent-with-inheritance interacting with his mechanism of natural selection, while Paley looked at the same evidence (the appearance of design in biology) and interpreted as supporting the inference of a designer. (The more modern "neo-Darwinian synthesis" approach to evolution puts more weigh on differential reproductive success rather than out and out inter- and intra-specific conflict, but that's a minor change of emphasis.)

That fundamentally remains the case in the non-debate over the reality of evolution - is it the result of natural forces, or of a supernatural "designer", a.k.a. a god.

Comment Re:Okay. (Score 1) 41

So the mammoth was killed by humans.

Even TFS doesn't say (or claim) that.

analysis of cut marks - if any - could confirm that the animal was butchered by humans. Whether it was killed by humans is a distinct question. Not unrelated, but there never has been anything to prevent opportunistic gatherers from taking advantage of a kill made by other means - including old age, falls, enmirement. (IS that a word - coffee not takeneffect yet? Stuck in mud.)

Such coincidental finds, traps or kills may have suggested hunting and trapping methods to early hunters.

To demonstrate human killing of the beast, you need to find something like a spear point (or several) in important parts of the body. But that still leaves open the possibility of an animal downed by some other reason, then killed by pin-cushioning by humans. So what you really want is an animal with a (partly-)healed spear wound penetrating the hard anatomy.

I'm not someone who follows this line of research myself, but I know that there are multiple examples of healed tooth scars in the dinosaur corpus of fossils, and in other areas of palaeontology, so I'd be fairly surprised if the type of specimen wasn't known at all. Whether this specimen shows such evidence is another question.

Comment Re:Yeah, I thought this problem was solved (Score 1) 118

Hmmm, they're all (in high enough concentrations) pretty effective biocides, and given their propensity to oxidise the living daylights out of anything, they'd probably be biocides against silicon-based life forms, if such a thing existed.

But whether H2O2 is more expensive ... a bit thornier a question. Yes, it's a continuing cost for chemicals. But there is a continuing cost with UV for both the electricity to run the lamps, the plumbing and pumps to force the water past the lamps ; the lamps themselves have a finite lifetime and need monitoring (another on-going cost). Similarly ozone made using a silent electrical discharge draws the juice too, needs plumbing, there is likely to be wear/ corrosion eventually on the electrodes, you still need pumps to mix ozone and the water. And monitoring, including of ozone discharges in many jurisdictions, because it is a VERY potent gaseous poison.

From first principles, I couldn't say which would be cheaper. I'd suspect that it would differ on a case to case basis.

Comment Re:The great nation ... (Score 1) 112

Ever plugged in your smartphone to your machine to maybe, synch something?

Err, not as far as I know, no. I never did understand this "sync(h)" thing, or how it differs from copying the files I want from one storage device to another.

But the laptop does make a convenient charger for the phone. It's a pity that it is such an absolute bummer finding my data on the phone and getting it off. It completely destroys the potential utility of a smart phone.

Comment Re:Ignore the "humans almost went extinct" bit (Score 1) 54

That's not from the Nature letter; apparently that's some off-the-wall addition from the submitter.

There is a coincidence of timing. However, given that previous estimates for this particular sector collapse (see my comment elsewhere for the dozens of other "recent, geologically" Atlantic sector collapses) were between 50 and 150 thousand years ago, it is little more than coincidence.

If there were a tight human population bottleneck (as opposed to a more drawn out but less severe one, with comparable cumulative genetic effects) of a few dozen generations (a thousand years, for a round number), you could fit this localised problem, the global Toba problem, and a Yellowstone super volcano all into a mere ten thousand years and still have several thousand years left over for humanity to continue expanding at 5% per generation (1 extra child per 20 families per generation), giving easily a 10-fold population increase to offset a 9-fold decimation.

Comment Re:Are and storms that fierce on Mars? (Score 1) 120

That's an effect, but unless you increase the viscosity of the (saltus, 'a leap') grains don't stay suspended for more than a couple of seconds once the turbulence drops even for a small amount.

If you look at rock pedestals, then their most severe erosion is strongly at the base. Compare the images with a more typical pyramidal hill to get the difference in erosive force between base and top.

Preventing landed craft from over-tipping with such a strongly concentrated low-level force is a job for outriggers. As the images show, the basic problem is hardly rocket science. You can make the engineering as fancy as you want to cut down weight (e.g. - two only outriggers, which can be re-positioned at ~120 degrees to the wind direction ; the weight of the re-positioning equipment being less than a third outrigger?)

I'm perfectly willing to accept the "stranded on Mars" as a MacGuffin. But that doesn't make it any the less of a hazard that would be addressed and managed. Hey, I could even take it fi there were an inconveniently situated Marsquake in the middle of a dust storm. Or a tube cave opening up under the lander because of the stresses of the lander. But it's still a MacGuffin that flies as well as the Maltese Falcon.

Comment Just for some context ... (Score 1) 54

When I was taking a volcanology holiday a couple of years ago on the Canary Islands, the count of recognised deposits from mega-landslips around the island group was 23. Many more were unrecognised, probably, due to having been overlaid by more recent landslips. The period during which these were deposited was probably only 10 million years, for an event every half million or so years, and each would probably have had significant effects between Brazil, Newfoundland, Britain and Morocco.

The Cape Verde islands are a broadly similar island group, a thousand miles to the south. So a broadly similar history can be inferred - maybe Brazil would get hit a bit more, and Newfoundland a bit less. So you're now looking at events every quarter million years.

Don't forget the Azores, on the Gibralter-to-Mid-Atlantic transform fault. There;s sector collapse risk there too. And no small risk of sector collapses in the volcanic Carribean islands too, some of which could reasonably be expected to propagate out into the Atlantic too. Say a cumulative risk in the order of once every 100,000 years.

It is not news that these risks exist, and have existed for longer than humanity has existed. And there is nothing realistic that we can do about them. Except not live too close to coastlines.

Comment Real World? (Score 1) 120

how a real world interplanetary spacecraft would pull off a rescue maneuver

Well, for starters, they wouldn't leave someone behind who wasn't dead and buried. "Dead" in the sense of "injuries incompatible with life" and/ or "failure to revive" and/ or "decomposing". This has been established by long history of mountain, cave and other remote area search and rescue incidents. If you want a ball-shrivelling account of how hard it can be to tell, read Joe Simpson's "Touching the Void" (the film wasn't too bad either; but remember that despite having been filmed by Hollywood, the events were reality. Including the crawling through the shit garden).

I suppose I'd better go and RTFA, but having just come back from a 2-million dollar/day operational planning meeting, the plan of "don't get into that situation" plays a really important role here.

Comment Re:No new components needed (Score 1) 153

Yes, I couldn't see a demonstrated need for new hardware or sensors in TFA either.

The last time I cared about what went on under the bonnet of a car (beyond "why doesn't this run?") was for my second car, in the late 1980s, made with 1970s technology. That had EGR. which I had to get an understanding of, because the line between the EGR valve and the inlet manifold, which used inlet suction to provide the force to allow the recirculation valve to be opened against it's spring had leaked, resulting in a failed emissions test when they were introduced. That was an analogue system, playing throttle position against exhaust and inlet pressures to sense when to open change state of the EGR valve. It worked.

I would expect that digitally controlled cars have much the same hardware, but with valves under solenoid and computer control, not pressure switches. So, no need for new actuating hardware here.

The author also didn't say what new sensors were needed. Every VW I've driven in 20+ years has had a sensor that would tell if it were on a dynamometer or not. It's the driver's seat load sensor. The one that turns on the seatbelt warnign light if the engine is turned on when someone is in the driver (or passenger, or rear - varies by model) seat. No driver AND engine running? On a test track.

I'm sure there are more subtle ways it could be looked for too.

Comment Re:America (Score 1) 395

I pray that the US gets a Churchill next election and not another Chamberlain.

In a testament to the efficacy of prayer, you're being given a choice of Donald Trump's wig, a deranged god-squad surgeon, and a number of non-entities. Oh, and the third round of a dynasty of hereditary presidents.

Well done, Bin Laden!

Comment Re:I've always said (Score 1) 241

I recant my position, man is inherently peaceful, and non-violent. Howzat?

Which fictional universe do you live in?

Definitely there is violence in the make up of humanity. Whether that violence is the dominant component of human psychology is something you haven't established. Whether humans are substantially different in this respect from any other organism on the planet is also yet to be established.

Some of the basic factors of human physiology - for example the very limited male-female differences within the species - actually argue the humans are less selected for intra-specific violent conflict than other primates. Look, for example, at the canines of most of our fellow primates and you'd see evidence that violent intra-specific conflict is a stronger selection force in most primates than it is in humans. And by contrast, the cooperative behaviour is a more significant factor in human evolution than it has been in most other primates.

Which is not to accept the straw man you're also propping up to have another tilt at. The reality is almost certainly that the situation is more complex than either straw man that you've presented. Which doesn't make for for attractive sound bites.

I bet you're thinking about bringing technology into the discussion. I rather doubt that the few thousand generations since human technological progress started to rise has fundamentally re-shaped our biology. (And the anthropological record is with me on that. Go back tens of thousands of generations into the Homo erectus and/ or habilis lineages and you'll still see lower levels of sexual dimorphism than in most primates. Securing the calorie resources to raise that infant through it's extended infancy is a long drawn out process that has been essential to every single generation of our ancestors whereas violent conflict is a much more sporadic influence. And the depressing fact (for people with a "Flintstones and Raquel Welch in a fur bikini" view of human evolution) is that it is more efficient to collect those calories by gathering than to chase mastodons across the landscape. That is how most humans acquired most of their their calories throughout history, and still is recently with the development of agriculture over the last thousand or so generations. Those techniques are mostly (today ; it's harder to tell in the archaeological record) a female-led activity rather than a male-led activity.

Just as a matter of interest, does your testosterone-fueled view of humanity represent your personal biochemistry? That's not a given, you know - it is (remarkable, I know) possible to harbour thoughts in conflict with your hormones.

"Anyone attempting to generate random numbers by deterministic means is, of course, living in a state of sin." -- John Von Neumann