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Comment Re:Does this mean more fuel for thrusters? (Score 1) 58

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?

Maybe, maybe not ; for a number of possible reasons.

(1) Do the main and attitude drive systems use the same fuels? For the large number of anticipated firings for the attitude thrusters, you'd maybe go for reliably hypergolic fuel/ oxidiser couples (i.e., on contact, they ignite). But for the main engine with only a handful of planned firings you might choose a monoprop with electrical ignition. That question is readily amenable to research.

(2) Is there a cross-feed system from main thruster fuel tanks and pressurisation to attitude thruster fuel tanks and pressurisation? Or, to rephrase the same question - is there a mission-critical need for such a cross-feed? Because if the system isn't absolutely essential, it would have not been designed. Remember that every valve (not "most" but "every") and every joint in a pressurised fluid system is a potential leak point. Again, if you find the plumbing design drawings, it's the work of moments.

It'd be fantastic to get some really good pictures of Europa (life!)

Any life on Europa which isn't considerably more technologically advanced than ours is going to be on the underside of 30-50km of ice. Now, ice pictures can be pretty, but it's a monomineralic rock with a coarse grain due to regular resublimation and/ or refreezing. Even under crossed polars and thick sections, "dull" is going to come to mind. (OK - I've probably done a few hundred thousand rock descriptions more than you. I've a higher "dull" threshold than most people for rocks. But "dull" will come.

and Io (volcanoes!).

Now you're tempting me. But not strongly enough.

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

Nowhere near enough. Decades isn't remotely good enough. When we're talking about (potentially) wiping out the only other origin of life in the universe from our own ... I'd put the "you fuck with not" time scale at several times the duration of our genus. Ten million years is a reasonable round number to start upwards from.

NASA would seem to agree with me - hence the dive into Jupiter.

Comment Re:Too bad we don't have 1977 technologies anymore (Score 1) 58

this is the kind of banal reply I predicted the GP would get. Don't you think everybody and their dogs already know what you wrote?

Shooting an anti-science ignoramus like hcs_$reboot in the arse is generally a positive contribution - to humanity in general and Slashdot in particular. Unlike your utterly useless comment.

Comment Re:Misleding headline (Score 1) 80

I thought exactly the same too. And I've spent years hanging my life (and other people) off "self-driving bolts" driven into limestone cliffs etc.

The "self-driving" designation, for Hilti, at least, refers to "in this package are a combination of hole-cutting bit and permanent anchor" ; you're still expected to supply the power (elbow grease), holding tool (a sort of cold chisel body), and final connector (which threads into the bolt, and has a head of your choice for your application).

Actually, Hilti still supply the final connectors, but not the single-use bits. And I can understand why. They take real care from the end-user.

Comment Re:Money back (Score 1) 142

If you brought it on a credit card, and the company in question was selling it prior to it receiving it's CE/ EN approvals, then you've got grounds for a chargeback on the credit card, and let their 363kg (800lb) legal gorillas argue it with the manufacturers/ importers.

But those approvals concern electrical safety - which hasn't been challenged. Whether the CC company would take the manufacturer/ importers failure to realise that data protection laws apply .... much more dubious. But you're better positioned with a 363kg gorilla leading your fight. If you paid by diect debit or whatever, you're pretty fucked. try to sell them to Americans. NSA staffers for their family's kids, perhaps. You might even cover your arse by making the "supplier's packaging" that describes it as a "covert spy doll" with more decorative interior layers of packaging for the target to see.

Comment Re:Holocaust 2.0 (Score 1) 142

Let me respond... as an actual, real life, genuine, pure-blooded... recovering Jew... I can't tell whether I should take offense to this or laugh my ass off at it.

Surely you can do both? Public ridicule is one of the most effective responses to offending events.

And then you can use the fence for something useful.

Comment Re:Super NES address space is far from linear (Score 1) 171




Old joke :
Masochist to Sadist : "Bite me, beat me, fuck me! Come in my arse and tell me you hate me!"
Sadist (with the sneer of a British Butler to an under-gardener's assistant) : "No."

In reality, there was probably a set of reasons more like
(1) we've decided to use these chips because they're cheap and promised to be available for shipping in 8 weeks ; here are prototypes.
(2) Software Div. needs to write this sort of data in 32bit words and read this in 64bit words. So we'll do that.
(3) Testing called on Friday about last week's version ; on memory block #4 they get errors because the readout isn't fast enough, so if we mirror that to here we can do interlaced async reads and get 30% better readout rate. So have that ready for Wednesday. And Software want blocks #6 and #8 to be 32bit ROM words but block #7 to be 64bit RAM.
(4) the chip fabbers say they should get 3% higher bus stability, but we don't have time to deal with that and we'll assume the production chips will be as unstable as the preproduction examples we've got. Get to it!

Comment Re:that's it. the end game. (Score 1) 388

f I actually wanted any of the extra benefits like medical. I don't go to the doctor in the last 5 years, because I have too much work to do.

At least one person in this exchange doesn't understand the meaning of "insurance", and I spent a year at college doing Statistics with second highest exam results for the year.

Which is understandable, I suppose, if you have "free at the point of use" healthcare which is paid for through general taxation ; you may mistake the medical premiums as being "payment for the doctor", while in fact they're a fixed fee for there being a doctor (hospital, MRI, oncologist, whatever) to call. You know how your car insurance covers claims over a certain amount (the "excess", in our terminology ; yours may differ, but the concept will be there) ; well your medical insurance does similarly, but with a more complex list of exclusions.

Comment Re:CRISPR for the masses (Score 1) 168

Creating such an artificial environment in space "from scratch" may be much harder, than using the readily-made planet.

Do you have any idea of the gigatonnages of material needed to terraform a planet like Mars to Everest-summit-at-the south-pole levels?

For Mars, to bring it up to an average atmosphere that is merely lethal (0.1 bar - your tears would boil - followed by your blood) you'd need to deliver around 800kg of suitable gasses per square metre. That's around 2*10^19 kg for the whole planet. Something like 1% of mass of the asteroid belt, if it's as volatile-rich as the gassiest areas seen by Dawn on Vesta.

Essentially, you're going to need to mine most of the asteroid belt for gases to terraform Mars. And you're seriously going to propose that level of exploitation without - as a pure side line - learning how to live in space? Not going to happen.

(Another tiny factor for terraformers to contemplate : Earth surface = 511 million ; adding Mars would get you another 144 million (neglecting any Martian oceans - which I can't envisage you having a vaguely stable environment without), less than 30% of our current land area, or around 2 gigapeople worth.

What benefit are you expecting from terraforming Mars again? Or is it total wish-fulfilment fantasy?

Comment Re:What the heck is "BCE"? What's wrong with "BC"? (Score 1) 118

Doesn't change the fact that everyone says AC and BC.

This is flat out untrue. It could only be true if you spoke to no-one in your "real life" experience who had any background or interest in one of the historical sciences. It's possible that you have such a benighted existence, but I hope you have a more varied life than you imply.

I really doubt you (yes, you as a person) say in real life CE

I do say CE / BCE in real life. Whenever we're talking about historical matters at the pub - e.g. with the digger-driver with his collection of locally found stone tools. Or when talking about the several Neolithic to possibly Iron Age burial structures in the area.

Why would you not use the correct terminology? The one thing we can be sure about is that the arrow-knappers and burial-makers were not Cleesian due to this being centuries to millennia before the claimed life of Cleese

Comment Re:What the heck is "BCE"? What's wrong with "BC"? (Score 1) 118

The change from Nicene terminology ("Anno Domini" & "Before Christ") to Common Era terminology is certainly not an American-versus-RestOfTheWorld question, nor even a particularly religious question.

Hanging a dating system off on specific person's birth date has certain problems for historical work, in particular, some historical facts are needed about this person (call him Cleese, and we can all perform the Parrot Sketch before shuffling off) - such as the day of year that Cleese was born on (not in any of the manuals - indications of winter, maybe around the winter solstice?) ; also the year would be a good idea (from 1952 to 1957 BP, as defined above, even according to people who accept the next point) ; and finally, it would be a good idea to be confident that this Cleese person actually existed.

To get around these multiple problems of historical detail, the Common Era is set up to align with the astronomical measures with 0 CE being 4713 years after the last time that the Solar, Metonic and indiction cycles of eclipses and the Moon combined. Simple.

Comment Re: Declining fields and Pole Reversals. . (Score 1) 118

It's only since (approximately) 1750 CE that people have built kin's out of "fire brick", loaded them with prepared forms (with glazes, etc), spent days firing them up and cooling them down, then carefully emptied the debris and successful product out of the kiln before re-use.

Before then, the kiln was built around the charge of forms using basically the same clay as the forms, the fire started in the integrated hearth (chimney also integrated to draw the fire), and the charge fired up over several days before the fire was put out and the kiln allowed to cool to the point it could be torn down to unload. Posh kilns with a lot of clay supply might make a hearth and kiln floor of fire brick for re-use, but generally it was as efficient a system as building a space ship then throwing it into the ocean after using it once.

Comment Re:Paleomagnetism (Score 1) 118

Using magnetostratigraphy (field strength changes compared to a standard - usually ocean core sediments - with a magnetism-independent dating method, such as biostratigraphy or tephra beds) is old hat. The new idea here is that the tax seals provide a date for each sample, and the magnetic traces in the pottery provide an estimator of the field strength at that time, increasing resolution of the variation in the geomagnetic field in the past.

Clear as mud now?

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