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Comment: Re: Dobsonian (Score 1) 187

by RockDoctor (#47797373) Attached to: Slashdot Asks: Cheap But Reasonable Telescopes for Kids?
Go back and re-read my post. I only mention a dark sky as a sideline.

You can have a sky utterly devoid of light pollution and iit still be utterly useless for astronomy by dint of driving rain or scudding cloud, even withut the precipitation. With around 2/3 of nights unusable, that is the main reason that I shipped my telescope off to my sister's country guest house. On those rare occasions that it does get used, it`s much better there than in my home town. But that`s still only a few nights a year that it gets used.

Going back to the original question - what is the most effective use for getting kids interested in astronomy (or whatever the Q was - I can't remember now) - then choosing your time and place is going to be important. Making a big build up and then being washed out by the rain (or snow, or in high summer, fog) is going to be more effective dampener than taking an opportunity of good conditions and using it there and then.

Comment: Re: Washington DC think tanks (Score 1) 458

by RockDoctor (#47797329) Attached to: Cause of Global Warming 'Hiatus' Found Deep In the Atlantic
"Civlisation - I buy it with my taxes!" Or some failry similar quote. There used to bwe a regular on here who used it in his signature. I can't remember if it was a Robert Heinlein or Thomas Paine quote, but it was someone who you wouldn't normally expect such thoughts from.

Comment: Re:Use Smaller poles (Score 1) 202

by RockDoctor (#47786569) Attached to: How the Ancient Egyptians (Should Have) Built the Pyramids

Use lots of smaller poles and make it really roll like a cylinder.

You'd get into a law of diminishing returns in rolling resistance compared to the complexity of the modification. You could probably turn the octagonal section of the modified (cuboid) block into a dodecagonal section by using rods of two or three different diameters and lashed into (their term) "mats" before being lashed onto the block. But whether it would be as stable, is one very open question ; whether it would be as strong under cornering (which would preferentially load the thinnest rods in the "mat") as the octagonal-section / dodecahedral-enveloped system that is proposed here.

Hmmm, I'm trying to remember my crystallographic space groups. Dodecahedra are in the same space group (class) as cubes (it's the secondary axes of 3-fold rotational symmetry that matter), so by choosing the arrangement of rods in the mat you should be able to make the envelope into a true (Platonic) dodecahedron envelope. Contrary to the paper's illustration, you'd need to attach three trios of "rods" to the three pairs of faces so that the ends of the rods protrude over the faces of the (cubic) core. And you'd need two different lengths of rods, to round off the corners. And I'm falling into exactly the same "diminishing returns" trap that I'm pointing out under your feet.

There's some interesting geometry there. And since I'm sharing an office with a lifting-slinging-hoisting-crane operations instructor, I think I'll shove that paper under his nose because he likes fiddling with scraps of rope (a "marlinspike seaman" as they were called in my youth), and I think he'll be interested.

It's an interesting idea. But it does clearly contradict the evidence of the contemporary records, which is a BIG strike against it being true.

Comment: Re: Nature is fighting against gays... (Score 1) 134

by RockDoctor (#47764099) Attached to: 13-Year-Old Finds Fungus Deadly To AIDS Patients Growing On Trees
Substituting EVD (Ebola Virus Disease) for HIV/ SIV, and bats for primates ... and you've got a good description of the probable source mechanism of the current Ebola outbreaks in West and Central Africa.

Incidentally, "improper animal handling procedures resulting in blood-to-blood contact" may include chopping up an infected animal for dinner (as most people envisage it), or digging bits of splattered bat out of the radiator of your car or from your clothing after the bat has become road kill. Which is certainly what worries us and our medical advisers as we travel near to infected areas.

Comment: Re:Average lifespan is misleading (Score 1) 281

by RockDoctor (#47764021) Attached to: The Evolution of Diet

We tend to make the assumption that an average lifespan of 30 means that nobody lives past 35 years old

We who? I doubt anyone thinks that.

To misquote someone, nobody ever lost money by underestimating the statistical ineptitude of the common man. Or something like that.

I wish it were true that nobody really thought that poorly. But I am realistic enough to recognise that there are significant numbers of people who really are that ignorant and incapable of basic maths.

Comment: Or stay offline. (Score 1) 275

by RockDoctor (#47763987) Attached to: Dropbox Caught Between Warring Giants Amazon and Google

But that might be the only thing keeping us from choosing between the Wal-Mart-A and Wal-Mart-B of online storage.

I carry 2x1TB drives around with me, and synchronise between them. No online storage for me.

Then again, with 1MBPS of public network link shared between 180 people, no online storage for anyone on this job either.

Comment: Re:Global Warming? (Score 1) 273

by RockDoctor (#47763955) Attached to: Numerous Methane Leaks Found On Atlantic Sea Floor

We're dumping centuries worth of CO2 into the atmosphere every year.

Looking back into the rock record (I used to use the rocks associated with this event as steering information to earn my bread and butter ; I work in a different part of the world this year), we've released as much CO2 in under 2 centuries as the PETM (Palaeocene-Eocene Thermal Maximum) took around 6 millennia to release. Dull, boring fact - like I said, my bread and butter for over a decade.

(look at the "clathrate gun hypothesis" for an example of what could happen).

s/clathrate gun hypothesis/PETM/ (or the interface between Forties / Andrew Sand Formation and the overlying Sele and Baldur Formations (spellings vary between countries and companies).


Dull boring facts, again.

Global warming deniers can bullshit all they want. Here in the oil industry we've no doubt what is happening. If our managers (not being geologists) want to lie about geology (or pay shills to lie for them), that's politics, not geology.

I suppose I'd better go and drill my hole in the ground now.

Comment: Re:It's only ahead of Siding Spring by a month (Score 1) 67

by RockDoctor (#47763867) Attached to: Mangalyaan Gets Ready To Enter Mars Orbit

Will it have time/fuel to "duck and cover" by getting to the far side of the planet before the close approach of the comet and the potential of a cometary dust storm that could wreck it?

While this is a non-zero probability event, it is a low probability event. I doubt that the mission planners are particularly worried about it.

Maybe if there's a mission-compatible way of sequencing things that will reduce this low probability even further, at little cost (which is what Hubble did during a predicted Leonid meteor shower ; but the Hubble Deep Field South was already planned, and the only real change was when the exposures were scheduled. Which by coincidence pointed the HST away from the radiant of the meteor shower.)

Incidentally I note that the mission is being monitored by the Indian Deep Space Network. Which either operates for a few hours a day (per mission, depending on direction to the spacecraft), or indicates that India has done some significant multi-national diplomacy to get their ground stations into a number of countries.

LMGTFY. There's a Wiki page that says it's one site near Bangalore. And that mentions the use of steerable antennae to " improve[s] the visibility duration". But this site says there are a number of other tracking sites. "ISRO Telemetry, Tracking and Command Network (ISTRAC) [...] has a network of ground stations at Bangalore, Lucknow, Sriharikota, Port Blair and Thiruvananthapuram in India besides stations at Mauritius, Bearslake (Russia), Brunei and Biak (Indonesia). " So, maybe several different organisations, with overlapping missions and facilities. Like Topsy, it's probably something that "just growed".

Comment: Re:Things (Score 1) 191

by RockDoctor (#47763271) Attached to: Slashdot Asks: How Prepared Are You For an Earthquake?

A short-wave transciever could come in mighty handy should disaster come.

Several people each having working and mutually compatible transceivers would be much more useful. So you need to have been, in practice, drilling with your local emergency services professionals to ensure that you know how to contact them, what to report and how to triage ... in short, you need to spend considerable time practising these things.

Which is why, on the vessel I'm working on today, we spend about an hour a week on safety drills involving the whole crew (on-shift and those nominally asleep ; nobody sleeps through those alarms). An hour a week ; 52 hours a year, or 6 and a half working days a year. That's the sort of commitment you need to make to be significantly useful. For a less focussed "how to be effective in a major emergency" level of preparation, you'd probably still need to devote a full weekend a year. Which is do-able ; but it's a lot more than having some particular piece of equipment and then not really knowing how to effectively use it when the shit hits the fan.

Comment: Re: Dobsonian (Score 1) 187

by RockDoctor (#47763131) Attached to: Slashdot Asks: Cheap But Reasonable Telescopes for Kids?
If you're going to be strict about getting the absolute best out of the budget, then spending more than a trivial sum on optics is a complete waste for most potential astronomers, regardless of age. Most of the budget will need to go on getting away from light pollution.

you could argue that is only some 50% of the target audience, but it's still 50% who you're going to need to ship dozens or hundreds of km to decent skies.

Alternatively, allocate 20 or 30% of the budget to dark sky advocacy work. You could even use a "reduce waste" slogan like "why pay to light up the bottom of the clouds?" Which raises another point, always a bugbear of astronomy, the weather.

Comment: Re:Dobsonian (Score 1) 187

by RockDoctor (#47753295) Attached to: Slashdot Asks: Cheap But Reasonable Telescopes for Kids?

not bore them to death trying all night to set up their mounts.

It took me about 15 minutes to polar align my first ever telescope, on it's first night after delivery. It's not rocket science, and it's not as difficult as you seem to think.

I will admit that the manual was pretty decent on this point, and I'm the sort of person who Rs T F-ing M before unpacking anything else. which isn't a normal 11-year-old's natural trait. But so what? On the first night, you set up the scope and get them hooked. First night is for seeing sights. If that works, then there will be other nights for them to learn the hobby. If the first night doesn't show enough goodies, then there won't be a second night.

Comment: Re:Cheap grid storage (Score 1) 442

by RockDoctor (#47749189) Attached to: Is Storage Necessary For Renewable Energy?
Reported reserve growth is common. Changes in prices (and extraction technologies) alter the economic cut-off at which a deposit becomes an economically-exploitable reserve.

Actual growth of a reserve is much much rarer and much slower. It takes millions of years to cook a source rock and generate hydrocarbons ; it takes more millions of years for the hydrocarbons to migrate from source into a reservoir. Most ore deposits also take extended periods of time to form, with consequent slow absolute production rates.

When oil prices were rising (a joyful period - it's around 10 times the price now compared to when I entered the industry), there was a bunch of economists who'd make a lot of ill-informed comments about how the rising prices meant there was literally (not figuratively) an infinite supply of oil available. Which goes to show how delusional some economics professors can be. Some of these people really do need to go out and take a hammer to a lump of granite for an afternoon - it's both educational and therapeutic.

Repel them. Repel them. Induce them to relinquish the spheroid. - Indiana University fans' chant for their perennially bad football team