Johno
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How Humans Could Get to Mars in Weeks, Rather than Months
Johno replied to Rascal Nag's topic in The Lounge
Endeavour: Well, if RTGs are available to you, a full scale nuclear reactor would seem to be unnecessary complexity for most applications. You could easily[1] build one using molten lead or sodium as the coolant, and keeping steam water under pressure; but the question would be simply why one would bother. Rascal Nag: Most of the advantages to Thorium you list will also be part of the next generation of Uranium reactors by default. The trick is that Thorium is fertile, not fissile; this means that rather than having large atoms that can easily be split to release energy, such atoms can be generated in a breeder reactor. But the next generation of Uranium reactors will ALSO be breeders, so instead of the highly radioactive, rare and expensive enriched uranium in current reactors, they will be able to use depleted uranium or natural uranium, which are both abundant and cheap (and as safe as thorium in most respects, though their oxides are slow poisons [similar to lead]). To be clear, I\'m massively in favour of Thorium reactors, but it needs to be said that the Uranium reactors are (at this stage) a much more practical concern. I firmly believe that Thorium will get there, especially if we pump in the money and time it deserves, but for now we can do much of what you say with Uranium. [1] For a given value of easily! -
How Humans Could Get to Mars in Weeks, Rather than Months
Johno replied to Rascal Nag's topic in The Lounge
I have to break in here. Radioisotope Thermal Generators, or RTGs, are NOT \'nuclear bombs in space\'. They are simply a small pellet of radioactive stuff used to generate a hot point in space, nothing more and nothing less; you can generate electricity from the heat gradient. They\'re not even truly a nuclear REACTOR in space. Reactors rarely hurt people, but they CAN in bad situations. By contrast, the only way a falling RTG could hurt you would be impact damage if it fell on your head. Incidentally, for the reasons I have just outlined, the idea of using thorium reactors in space isn\'t actually relevant - they don\'t use Uranium in RTGs, but an isotope which will produce heat for the required time (often, but not always, plutonium). Finally: Thorium reactors are safe because they\'re new technology reactors. We can make Uranium reactors as safe, with the advantage that we don\'t have to develop a whole new fuel cycle for them. -
'Spray and pray' seems to work better than 'carefully aim each shot'. But it costs a lot. On that subject, the cheapest way to get paint is with your initial pack. Buying an extra pod here and there will cost you a lot more than the 'Rambo' or 'Terminator' pack - plus often they give you better gear into the bargain. If you\'re with a group of friends, SHARE AMMO. In the long run it\'s much more fun to play 5 games in which everyone plays than 10 games in which the same 3 guys with lots of bullets are the only ones on the field! At lunchtime, eat everything you can stomach (and, in your case [if memory serves me correctly], anything Halakha allows!). Trust me, no matter how much food is on offer, your body will use it all. WEAR A PROTECTOR. In Australia, we use the ones designed for cricket. I don\'t know what is available in your country, but not to put too fine a point on it, if you ever intend to have kids of your own, you\'ll need to ensure that no shots get you where it really hurts. One guy on a group I went on thought he\'d be fine without it; they\'re unlikely to hit me there. [They carried him . . err . . her off. ] You\'ll notice that when you start the game, a bunch of guys will walk in like they were Dirty Harry himself. Don\'t pay any attention to them; they\'re the noobs. It won\'t last past the first paintball in the head. Instead, you duck behind the first piece of cover you can find, even (especially!) if that happens to be another player. Hope this helps!
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So far I have managed to avoid it, although the mild cold I had earlier this year was the very devil to shake (not terrible symptoms, just hung around forever).
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Ah, right. We hear about bullfrogs a lot in American books/songs/whatever; but I\'ve never actually seen one.
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Star trek online "sorry we cannot serve to people under 13."
Johno replied to sss's topic in The Lounge
[mod] Okay, merging these two. Only need one thread for this.[/mod] -
My own would be a highly accurate simulation of Trafalgar-era naval combat. You\'d get the chance to first command a gun, then a gun deck, then eventually work your way up to captaining a ship (which you\'d command down to the very sail settings, but you could also leave the setting of sails to your first officer). From there, you\'d be able to command a squadron of ships; but you\'d have to do so by sending flag signals. No God\'s eye view in this game!
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What species, Nova? Obviously an amphibian of some kind, most likely a frog/toad.
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I can speak conversational French and Turkish (if the other person doesn\'t mind speaking very slowly! ). English being my native language.
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For the first three Lunar missions, Apollo used a free-return trajectory - a figure-of-eight loop around the Earth and the Moon that brought the spacecraft back. That way, if something had gone wrong, the spacecraft would have been brought back into the vicinity of Earth. After Apollo 13 (which started on a high elliptical trajectory but had to be brought back to a Free-Return), the later missions used an elliptical trajectory (which was free-return to the Atmosphere but fell short of the Moon) followed by a mid-course correction burn to put the spacecraft into Lunar orbit.
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Robert Ballard would disagree with you there. He believes (and he\'d know!) that we know more about the surface of the moon than we do about the bottom of the ocean, and that we\'re only now starting to realise the wonders that lurk in the deep areas.
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The best way to consider 40K is to imagine it as the biggest and most complex game of Scissors, Rock, Paper that the world has ever seen. Each unit can defeat another unit on the board. It is possible to design a list so that it will utterly crush another list, of course. However, it\'s a good idea to assume you\'ll not know what your opponent will field, which means a balanced list is a much better idea. And in those circumstances (more or less enforced by playing in a tournament, by the way - since you never know what you\'re going to be up against, so a one-trick pony is a bad idea), either player should have a fairly good chance if they know what they\'re doing. And that\'s what makes the game fun!
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Another 40K-er here. Reading (Does that count as a hobby?). Just getting into a new one - a few weird events have let me discover I have a very good Kermit the Frog voice, so now I\'m building a puppet to teach myself ventriloquism!
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BSOM180: What character is that? Is it from Girl Genius? Just looks a little gaslamp-ish . . .
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[mod]Okay guys, get this back on topic or else this topic goes down to the deep, evil darkness that is off-topic! Also, I recommend that any map including any objects such as . . you-know-whats, that may or may not be black, stone-like material . . should be spoilered. [/mod]
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That Thread In Which We Discuss The Merits of Different Systems of Measurement.
Johno replied to Charzy's topic in The Lounge
. . .Though telling my school kids that we\'re going to be adopting decimal time is a GREAT April fool\'s prank! As for converting between the two: Yes, I\'m aware of that (I do have to teach very basic physics, after all! ), but I\'m talking mainly as a teacher here. School kids often find that concept hard. Actually I\'ve never thought of approximating it to a whole number before . . . I do that with gravity (approximated to 10 ms-2), so why not? -
That Thread In Which We Discuss The Merits of Different Systems of Measurement.
Johno replied to Charzy's topic in The Lounge
I thought it might be worth giving a perspective from someone who has lived in the Metric world all of my life. Australia converted over in the 1960s (along with instituting decimal currency; don\'t ask what it was like before!). A few problems noted: * The lack of an in-between for centimetres and metres: As noted, the decimetre technically exists. In practice we don\'t use it. In fact, engineers and tradesmen rarely use even centimetres (although these are useful for day-to-day measurements in the household); most of the time, a carpenter will describe a piece of timber as being 1200mm long. For most of us, metres are perfectly good for big objects, centimetres for small ones. * Kilometres are a great measurement for long distances. My pace is around a metre, so a good approximation is to count a thousand paces, and I\'m usually at a kilometre (give or take 10% or so). * Speed limits are simple too - for suburban driving it\'s 50km/h, for arterial roads it\'s 60, 70 or 80 km/h (see signs), for country roads it\'s 100km/h and for freeways it\'s 110km/h. * Metres per second are used almost exclusively by physicists. That\'s okay, though - kids rarely have trouble understanding how to calculate them. Interconverting between m/s and km/h can be a problem; however, you seldom actually need to do it. * Once you get your head around it, temperatures in degrees C are easy (we almost always say 'Celcius' now, rather than 'Centigrade'). 0 for freezing, 100 for boiling. Incidentally, someone (forget who, sorry) described 22 as a warm day, 28 as a hot day - that\'s relative! For me, 25 is a nice moderate day and 35 is a hot day. 40 is stinking hot. I live in Western Sydney, though, so it\'s all about what you\'ll experience in a typical year. (The opposite is also true - for me, 6 degrees is incredibly cold; we don\'t ever get snow!). -
Ping: Don\'t worry about it. You\'re faced with a basic problem - nobody can see your face, so we tend to assume that any misconceptions you speak are because you\'re ignorant or foolish. Most people don\'t consider the possibility that you might just be young. This isn\'t a problem for me, however. I\'m a teacher. Dealing with the misconceptions of kids is what I do! (And yours are far from the silliest misconceptions I\'ve had to correct . . .) Anyone who wants to have a go at Ping: LAY OFF THE KID.
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I think 1/6G is probably enough for humans to live reasonably healthily. I can see where the Mars One idea is coming from - by initially sending only one Dragon, it simplifies the mission immensely. However, I think that if you were to send a couple of unmanned modules with life-support beforehand it\'d raise the odds of a successful mission considerably. One thing that is worth mentioning - it\'s not QUITE as bad as some people may think. Because of the shape and the method of re-entering, we tend to assume Dragon is basically similar to other blunt-capsule spacecraft - the Soyuz, the Apollo and similar. But the cabin size of Dragon is quite a bit larger; it can accomodate seven people. We should think of the crew compartment as being more on a part with the Shuttle. I\'d still rather have a lot more personal space than that to share with two others, but I can see that it\'s not as bad as people might think (especially if you have the equipment to perform EVA).
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I think the thing I loved was that with the technology available to us, we could all get access to the best telescopes for watching it online. Gotta love the 21st Century!
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Trololrolling has suddenly lost a lot of its humour . . . .
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We had a pretty cloudy day, but GIVE IT UP FOR THE 21ST CENTURY! I had images from the various observatories along the East Coast of Australia (plus occasionally one from Mauna Loa) on the Smart Board at School all day. Every class I taught got an ear-bashing about the significance of the event.
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Reproduction for long duration space missions?
Johno replied to VincentMcConnell's topic in The Lounge
Colmo\'s on the money. Much as people fantasise about zero-G sex, the fact is that we\'ve yet to even figure out a way to make it possible. The closest I\'ve heard is a woman in the USA who has developed a velcro jumpsuit designed to allow a couple to lock together in freefall. It was tested (nothing NSFW! Just connecting the suits, one kiss, then a disconnect) in a zero-G aircraft. However, none of the Space Agencies have shown any interest in performing more vigorous tests aboard the ISS . . . -
That Thread In Which We Discuss The Merits of Different Systems of Measurement.
Johno replied to Charzy's topic in The Lounge
The SI has the advantage of being easier to use, and it also interlocks a lot more effectively. -
Yes, up until now I\'d heard of using gravity assists to get robots to various destinations with a tiny booster. Generally speaking all plans that I am aware of for manned missions go direct.