Saturday, 3 September 2011

Bring Back The BBC Micro!

I remember when our school got a computer.  It was sometime around 1984, and I was about 8.  It was a BBC Micro (or maybe a model B, I've never been much of a hardware buff).   They were fantastic little machines made by Acorn for the BBC, who through a stunningly insightful move had initiated the BBC Computer Literacy Project, something that without a doubt is a significant factor in the lives of many computer professionals today.  And a good few amateur hackers, which is equally good.

Google's own Eric Schmidt recently lambasted Britain's computing education, and unpleasant as it is to hear he's absolutely right.  By the time I hit high school, the momentum built up by the BBC had faded.  We were taught to use word processors, spreadsheets and databases.  I don't recall doing any programming at all.  From what I've heard not a huge amount had changed.  Far more emphasis is placed on the use of applications than is on actual programming.  It's akin to a craft and design class showing you a chisel and then spending half an hour teaching you how to use a chair.

But back to the BBC Micro, the little silicon hero at the centre of this minor diatribe.

It was really quite brilliant.  This is pre-GUI remember, so Mrs Bott had to sit a wide-eyed eight year-old down in front of a black screen with a little white cursor, and explain to him that this was the future.  I knew that of course.  This was a TV that could do what I told it, I was living in one of my Asimov novels (the Lucky Starr series in fact).

And we programmed, us eight year olds.  Through a simple cursor on a screen, and some basic shell level commands, we made things happen.  Turtle was a particular favourite - part programming language and part game, you could control a little cursor on the screen that drew lines.  You could move forward and rotate the cursor.  I don't recall the exact syntax, but it was something like:


That would give you a square.  At this point we'd realise there was a quicker way, and were introduced to loops:


Did exactly the same.  And, of course, we'd all compete to make the best circle we could without killing the machine, so that's a basic knowledge of hardware limitations and the effect of big loops.  We were eight!

So why, I demand to know in an overly theatrical way, was I next sat down in front of a plain old terminal in 1994?  Ten years later?!  In a university physics class?  If I'd known at the time I'd have been bloody furious, ten years is forever when you're eight.

What happened in the meantime?  The school only had the one computer, and a lot of children, and no computing teacher.  They did the best they could, but there was never a chance of getting more than the odd hour on it, and you need more than that to really get into it.  Then I programmed the video for my parents a lot, and did a lot of whining about them buying me a computer.  Eventually, when when the cost/whining ratio hit a critical point, they bought me a Commodore 64, and I got to grips with BASIC.

By the time we had the mandatory-aged-14 classes on how to type and save a file I was fairly quickly convinced that computing education in schools had missed the point.

What would have been useful?  A bare bones computer the whole way through.  A basic UNIX style terminal with BASIC, maybe Perl.  Oh, the things we could have done and learned.

The thing is, these days that's possible.  If any kid wants to learn programming they should have free access.  Hell, we could easily provide a single decent computer for the school, and a lot of dumb terminals for the pupils to log in through.  But no GUI, that's the important point.  No windows (certainly no Windows), no mouse, nothing.   Certainly no internet.  Give them Lynx for Christmas perhaps.

We've lost sight of what made the brilliant programmers Britain boasts today.  It wasn't Windows and Word, don't be silly, those weren't even around when our greatest and brightest were learning.  It's a free reign.

Give them root access - give them a virtual machine.  Give them Perl and pwd and Apache.  Give them shell scripting and apt-get and sudo.  Give them SSH and vi and/or emacs.  Just give them a bloody computer and let them learn!  Yes, they'll break the computer.  And most of them won't want to admit it, and try to fix it themselves.  And some of them will manage it.  The ones that don't?  Well it's only a virtual machine after all, just reset it. 

It's not difficult (unless you're old enough to be an MP) and it's certainly cheaper than most of the nonsense spent by government these days.  How many virtual machines would a cool billion buy?  Cos that's what we spend on no trams these days.

Thursday, 18 August 2011

Like A Neverending Circle, Like A Wheel Within A Wheel

So, physics is cool again [BBC News].  This happens every so often, and as far as I can tell there's a chaotic element to the cycle, but it's generally on the order of decades.  Professor Brian Cox seems to be taking a large amount of the credit and/or blame this time around, and it's partly deserved.  He's clearly passionate about the subject and puts it across very well to a lay audience (although his colleague Jeff Forshaw [YouTube] is the one to look out for if you want relativistic hyperbolic geometry to be fun!)

I don't think physics is cool because Brian Cox is involved though, eloquent as he is.  In fact, I think Brian Cox is fairly famous at the moment because he happened to be there at the right time.  The very beautiful Wonders Of The Solar System, for example, wouldn't have been made if there hadn't been a public enthusiasm for physics in the first place.  Take a look at America, where Carl Sagan's classic series Cosmos is currently being re-made.  I bet America hasn't heard of Brian Cox, let alone D:ream, and yet physics is kicking off there as well.

It's a cyclical thing, and it's always huge.  Take a look at Einstein as a classic example.  He was one of the first modern superstars, a moniker that is remarkable fitting,  truly famous across the globe, and yet most people had very little idea what he'd actually discovered.  A few decades later we had Richard Feynman, then Stephen Hawking.  It seems all you have to do to be a famous physicist is break the mould a little.  Playing a musical instrument aso seems to help;  step forward Dr Brian May PhD, and one of the greatest rock guitarists to have ever lived.  I also maintain, against much opposition, that Wayne Rooney and others like him are great physicists, even if they don't know how they do it.  So they only work with dynamics under 1g and narrowband air resistance?  Well, everybody has to specialise.

There's something deeper to physics-cool than celebrity endorsement and TV documentaries though.  Physics is cool because it makes you look smart.  Everybody seems to have a strange impression that physicists are particularly intelligent, that it's a subject for geniuses.  That's generally quite wrong, it's a remarkably simple subject if you get your head around the rules of the game.  It is exceedingly good at making you look smart though. 

I've lost count of the number of times I've "cleverly" fixed something using what I learned in physics classes at the age of 15.  Problem with the ice machine in the pub?  Well, that's a transformer, I recognise the coils, and it's making that grid of wires hot because electricity does that, and they melt the sheet of ice that comes from there.  But that wire is broken...

Shazzam, free drinks for the night and a reputation as a super-genius thrown in. You get to look like The Doctor and Sherlock thrown into one. Steven Moffat is clearly a physicist at heart.

Physics is cool because it gives you some very solid ground to stand on when you need to build an argument.  You know the basics, you can rule out daft ideas at a stroke and concentrate on what's actually real, in front of you, and how you can use it.  If you are faced with a problem you've never seen before you've got a head start, because you understand the rules the problem has to obey.  Sometimes, just sometimes, you solve a problem by going right back to first principles, and that feels particularly cool.

Monday, 25 July 2011

Smug Mode: On

Last September, at the height of the Old Town Mouse Season, I posted some  observations that the mice in our flat seemed to have developed a distaste for poison laced grain, and suggesting that evolution of some description was going on.  ("Mice, Chickens, Eggs & Evolution")

Now I'll point out once more that what I do on this blog isn't actually science.  I have fun exploring science, yes, but very little I do is actually science.  The mouse thing sort of got close - there were repeated observations and the vaguest semblance of data gathering, but it was all very wooly.  "Anecdote is not a synonym for data" is a phrase you'll hear a lot.  "Correlation is not causation" is another.  The mouse thing wasn't science - an interesting angle to explore the basic idea of evolution from, but not science.

But now some real scientists with proper notebooks and letters after their name have taken the idea and turned it into proper science. They even got it published in a journal, Current Biology.

What they've discovered isn't precisely the same as my hypothesis.  I wrote:
For some reason or another they didn't go for the free food. Maybe it was the smell, maybe the colour, maybe they just didn't like the taste - maybe they're refined mice and expect more presentation than a small plastic tray.
Whereas Song, Endepols et al wrote:
Polymorphisms in the vitamin K 2,3-epoxide reductase subcomponent 1 (vkorc1) of house mice (Mus musculus domesticus) can cause resistance to anticoagulant rodenticide
Or, if you prefer, the mice have naturally bred a resistance to warfarin, the poison often used on them, rather than not even eating it in the first place.  It's actually a better tactic, because then they get free food as well.  I love it when the best laid plans come together.

Tuesday, 19 July 2011

Fear And Coding In The Highlands

It's not the most impressive life-changing-move as far as they go, but I've still been freaking out left right and centre for the last three months.  I was, previously, a science buyer for a the fantastic Blackwell's bookshop in Edinburgh's bustling Old Town.  Fun job, great people and reasonably well paid.
Now I'm an unemployed house-husband of sorts in the middle of the Scottish Highlands.  The nearest place of note is the village of Nigg (I'm a Niggle, since you ask), the nearest pub is 6 miles away, and if I want to get a reception on my mobile it's a 45 minute drive away.

That last one is a bonus in my book.

There are other bonuses too.  We're sat right in between two RAF bases and their bombing range, so the Tornado GR1s screaming overhead add a certain ambiance to Battlefield Bad Company on the XBox.  There are 360 degree kitesurfing beaches within a few miles, and the sky is BIG...

So what am I doing up here?  Well apart from avoiding a seven hour, £50 round trip to see the girlfriend, I've decided to go into web design and support.  I've got myself some rather funky servers in a data centre, I'm putting together the website, and I'm about to start advertising locally.  The thing I'm particularly keen on is the support angle - there's lots of people who want to set up a basic blog, or get started on eBay, or a hundred and one other things that geek-types see as being ludicrously simple - that's my target market, people who want things to be as simple and as easy as possible.

So, if you want a website, or something even funkier like an online app to do X, Y or Z then drop me a line:

Blatant plug aside, normal geek service will be resumed as quickly as possible.  I've been a little busy recently, what with moving everything I own a couple of hundred miles, plus having to build new bookshelves, but things are settling down.  I'm toying with the idea of exploring the history of science in the area, there's some cool geology for starters...

Friday, 10 June 2011

The Earnest Importance Of Zombie Plans

I was in the Scout association for fourteen years, and learned a lot about self-reliance, teamwork and initiative.  From day one a Scout's motto has been the famous "Be Prepared".  Prepared for what?  Just about anything is the point.  We were expected to look after the younger kids on camp, lead patrols on mountain expeditions, even run messages for the emergency services in the event of a major disaster.  It's an ethos that has served me well in the last thirty-odd years, and one that is frequently recognised by employers and the like as being a Good Thing.  Despite the whole boys-in-shorts image you have to remember that Baden-Powell based the training on the principles of a specialist military unit.

So where do zombie uprisings come in?  Well, zombie attacks are very close to being a worst case scenario for modern civilization.  The combination of a highly lethal viral style epidemic and violent civil uprising make them very difficult to deal with.  I'll have to admit at this point that I don't believe we'll ever actually see a Romero style Day Of The Dead, but the point is that if you can deal with zombies you can deal with anything short of a direct nuclear strike.  Be Prepared for the undead and you'll Be Prepared for most eventualities.

"Official" attitudes are slowly coming round to this point of view too.  The US Centers for Disease Control recently posted a slightly tongue-in-cheek guide to preparing for a zombie apocalypse which outlines their approach to a large scale outbreak and gives good advice on general disaster preparation.  "If you're ready for a zombie apocalypse," they say, "you're ready for any emergency."  And that's official government advice for US citizens.

In the UK we tend to be a little more reserved in our Armageddon preparations, but zombies are starting to pop up on the radar.  After a freedom of information request Leicester City Council recently admitted that they are "unaware of any specific reference to a zombie attack in the council's emergency plan", a situation that will hopefully be rectified as a result of the publicity generated.

Political bodies aren't the only ones waking up to the very real usefulness of preparing for Z-day.  In 2009 the prestigious journal Infectious Disease Modelling Research Progress published a paper entitled "When Zombies Attack!: Mathematical Modelling Of An Outbreak Of Zombie Infection".  (Munz, Hudea, Imad & Smith).  This perfectly serious (if lighthearted) paper uses proper epidemiological methods to simulate the effects of an uprising and concludes that quarantine and cures do very little to help - swift and aggressive action is required if we're going to stand a chance.  The models used have also found real world applications which do not require the undead roaming the streets:

The key difference between the models presented here and other models of infectious disease is that the dead can come back to life. Clearly, this is an unlikely scenario if taken literally, but possible real-life applications may include allegiance to political parties, or diseases with a dormant infection.
- Munz et al (2009)
The Munz et al paper also holds the distinction of being the only peer reviewed work I've seen which references Bainov and Simeonov's Impulsive Differential Equations: Asymptotic Properties of the Solutions (1995) alongside Frost and Pegg's Shaun Of The Dead (2002).

So apart from disaster management, bio/political mathematical models and some very entertaining films and computer games, what have the undead ever done for us?  I've got one more idea up my sleeve...

There are some mathematical questions which are very difficult to solve, the travelling salesman problem being a classic example.  One way to find an answer quickly is called ant colony optimisation, it simulates the way ants find their way around to find what is probably the right answer (note the "probably" - it's not a proof, just a good estimate).  I firmly believe that software zombie simulants can be used to perform a variation on ant colony optimisation - in fact, if we had a real zombie uprising in a major city we could use careful placements of unprepared people (or "bait") to find optimal taxi routes.  And that's something that's useful to everybody.

Wednesday, 8 June 2011

How Plastic Bags Will Save The Planet

A couple of years ago a bandwagon started rolling through the UK.  Led by newspapers, and with the supermarkets and the government as the main passengers, a large proportion of the public jumped on board.  The target of this bandwagon was the humble plastic bag, provided for free by almost every shop in the country.

Plastic bags, you see, are evil.  They come from oil, and as we all know we should be using less of that.  Plus they choke turtles and strangle swans.

So shops started discouraging their use - customers were charged for them, asked if they really needed one, and offered bigger, tougher reusable bags.  But I think we've missed a trick here.

We need to look at what the evils actually are.  Let's take the turtles and swans for starters.  Plastic bags don't have to harm them.  I've got a bunch of them in the cupboard above the cooker and I've never discovered a dead swan in there.  It's not the bags themselves that cause the problem, it's their disposal.  Jamie, our venerable 16 year old Jack Russell once got into the Christmas chocolate and ended up with some serious kidney problems for his trouble, but that's not Cadbury's fault, it was ours for leaving it in his reach.  Wildlife deaths are a littering problem, not a plastic bag problem.

So is using oil an evil?  Well, this is where things get interesting.  You can do lots of things with oil:

  1. Leave it in the ground.
  2. Turn it into fuel and burn it.
  3. Turn it into plastics.
Option one is clearly the most environmentally friendly, but I think I can suggest that's a fairly unlikely outcome.  The second is probably the worst as far as things go - if the anthropogenic global warming theories are correct then this option is the one causing most of the problems.  That leaves the third option, turning it into plastics.

As we all know, plastic doesn't break down easily.  Hundreds of years is the number you'll hear bandied around - but what's wrong with that?  It means your supermarket carrier bag, if disposed of in landfill, will sit there for centuries, doing precisely nothing.  It won't break into carbon compounds and interfere with atmospheric chemistry, it will just be in the ground.  It's a very roundabout and inefficient way of doing option one, leaving the oil in the ground in the first place.  Plus, once oil becomes scarce enough, mining landfill for plastics will become profitable, and cheaper than drilling kilometres under the ocean for the raw material.

So we've got two reasonable options open to us: use the oil for fuel, or use it for plastics.  As far as I can see, the environmentally friendly option is to go for plastics.  Lots of them.  So many that when we run out of oil we've got something to show for it: plastic bags galore.  A little more atmospheric carbon is slightly less useful to the average person regardless of environmental effects, plastic mines on the other hand...well if you want to be cynical about it, there's money in plastic mines.

What about the people who need fuel, which is most of us?  Well, we're hideously bad at using it.  We burn oil in car engines, which are horribly inefficient, only around 20% of the energy in the fuel actually gets used for something practical (unless you regularly cook steak on your engine casing).  Burn it in a power station on the other hand, and you get around 33%.  Use that to charge fuel cells and you've got a bit more bang for your buck, and some leftover oil to turn into useful and environmentally friendly plastic bags.  In time, of course, we'll run out of oil and be forced to find alternatives - why shouldn't we be doing that sooner rather than later?  Use plastic bags and bring the future a little closer.

And plastic itself can be used for transport - paragliders for example, even small ones...

Sunday, 6 February 2011

Fake Homeopathic Remedies For Sale

Let's make one thing very clear from the outset, because there's a lot of confusion over this issue: homeopathy is not a synonym for alternative or complementary medicine.  There are some forms of complementary medicine that do have a real effect on the body - chewing willow bark for example, because it contains a molecule that is very similar to aspirin, or using dock leaves for nettle stings.  Maggots aren't a traditional part of western medicine, but have been used very successfully in treating certain open wounds.  Complementary medicine isn't always bunkum.  Sadly, a lot of the time, it is. Or at best a well constructed placebo.
You know what they call 'alternative medicine' that’s been proved to work? Medicine.
Tim Minchin
 So I'm not having a wholesale go at alternative medicine here, just one part of it, specifically homeopathy.  Homeopathy is a very specific type of treatment based on the concept that the same thing that causes a symptom can treat it if used in small enough quantities.  So, for example, to treat insomnia you would give the patient a very, very small amount of caffeine.  The problem arises when you look at just how small an amount is used.  Homeopathic remedies are so dilute that, statistically, you'd be very lucky indeed to find a single molecule of the "active ingredient" in a dose.  Practitioners claim that water, the solvent normally used, has a "memory" of some description.  If this is the case, and can be shown with some reliable data and maybe a pie-chart, then there's probably a simultaneous Nobel Prize for physics, chemistry and medicine to be had, and at 10 million Swedish Kronor, or about 1m Sterling per prize, that's a lot of money to put towards a charitable homeopathic clinic in the third world.  I'm surprised nobody has claimed it.  Maybe they need some help with the pie-chart.

Suffice to say, I'm not a fan of homeopathy.  So I've decided to go into business.

Anybody want to buy some homeopathic medicine?  It's £2.50 a pop (plus p&p), which is half the average price of one of the main UK retailers.

The only drawback is that it's fake.  It's fraudulent.  I've had no training in making it, I don't have a leather thing to bash the bottle against and the remedy has never been close to the active ingredient I'm claiming it's made with.

So am I worried about being taken to court over this?  Well, yes it might happen, and yes it would bankrupt me (not that I have anything anyway), but I'm not in the slightest bit worried about a conviction.  UK law, you see, requires more than a simple admission. If I plead not guilty there has to be at least one other piece of evidence - in this case, some regulator or other would have to perform a chemical analysis on my fake remedy and show that it's got a different form of "no active ingredient" to the "no active ingredient" in a real homeopathic remedy.  I don't believe this is possible, even in principle, and if somebody does manage it then there's a few Nobel Prizes for them and I'll have been at the centre of one of the biggest scientific revolutions the world has ever seen.

If you would like to order any of my fake homeopathic remedies please comment below or email me, not forgetting to include details of the active ingredient/s you want me to not put into it.

Sunday, 23 January 2011

Artificial Intelligence Comments On Education Policy

There's a particular user on Twitter who is, in my opinion, the only user who's always going to be on the good side of average.  @cmunell is a little tedious in some ways.  She (I don't know, but it sounds like a she) doesn't really do much other than offer an opinion on some phrase she's learned somewhere.  To be honest, it's often not highbrow stuff; stunning observations such as:
I think "the-chart-show" is a ()
I think "North Creek Bridge" is a ()
I think "Dansville Municipal Airport" is an ()
 It's not anything big or clever most of the time.  Sometime though, just sometimes, she says interesting things.  She comments on people I've never heard of before, or a big economic/ideological argument in the UK at the moment:

I think "sarah marie johnson" is a ()
I think "educational books for kids" is a ()
 At this point I really have to stress for narrative, scientific and legal reasons that NELL doesn't know what she's talking about.

Well she might to be fair, which is kind of the point of this article.  I hope not though, not yet at least.  We're not ready for that.

NELL, you see, is a bot.  A computer.  Not even a computer really, as you could just change all the hardware, but she'd still be NELL.  She's simply software, in reality she's a set of instructions for a computer, she's ones and zeroes.

But she seems to be getting the hand of using the English language.  She's not always right by any means.

And I have to point out that I believe the "criminal" she's referring to is the same Sarah Marie Johnson who was convicted of murdering her parents in the US a while back.  Here's the court judgement I'm thinking of.

But if NELL isn't referring to that particular Sarah Marie Johnson (and I'm bet there's a few of them, and I bet they're bloody furious about articles like this...sorry) then is it a libel?  And if so, who gets sued?  Obviously I could be, for repeating it, but that would require the original statement be proved libellous.

So the question here is can a computer commit libel?  If NELL reads this article and concludes that Geoff Robbins is a criminal (and I've never been convicted of a crime), then could I sue?

Who?  The programmers?  They simply wrote a computer program, a scientific exploration of the human language.  And it's wrong sometimes.  Science allows for things being wrong; things being proven wrong is the lifeblood of science.  Science can never happen if nothing is ever found to be wrong.

But the law does not allow for incorrect statements in some situations.  In public, for example, and where the incorrect statement makes somebody look bad.  The call that libel, and it costs a fortune to just be accused of it.

Which has one effect.  It forces science underground, away from the public and into the private sphere.  Worse than that, it takes the innovative new ideas away from an international community and the general public (see AI on Twitter, this article), and it forces them into patent fenced commercial secrets.  Imagine a world where Einstein only allowed the nuclear military to use his ideas, and where Arthur C Clarke's satellites were useless for GPS because he'd never heard of relativity.  Secrecy makes the world worse, and libel law (in its current UK form and interpretation) forces science into secrecy.

And where does that leave NELL?

Would she like to play a game?

Is the only winning move not to play?

Saturday, 15 January 2011

First Science From The Planck Satellite - The Edge Of The Universe

Did you hear that somebody took a picture of the entire Universe?  It's slightly cooler than that, it's actually a picture of the Universe about thirteen billion years ago.  Or, more importantly, around 400,000 years after the Big Bang.

That's nothing.  As far as timing goes, that's a photo of the start of the Universe, give or take a bit of motion blur.  Well...sort of.  I'm being a little poetic, but it's the closest we can theoretically get to an honest-to-goodness photo of the Big Bang.

So yeah, it's quite impressive.  It's been done before of course, it was called the WMAP (Wilkinson Microwave Anisotropy Probe) which is a very complicated way to say "Human horizon map".

As I've previously mentioned on this blog, the Universe has an horizon.  It's not a two dimensional ground-sea horizon like we're used to (ie a line at a distance), it's a three dimensional horizon, a rough sphere.

And yes, it's centred on us.

That doesn't mean we're special.  We're not, we're a strange lump of matter on a small bit of debris orbiting a very average star in the backwaters of a galaxy that never amounted to much.

It's just physics.  The Universe has been around for 13.75 billion years, and causality travels at a certain speed.  Yes, yes, yes, we call it the speed of light.  That's wrong, it's a bad name and the world of science should do something about it.  "c", the physical constant, is the speed of causality.  Light happens to be one of the things that travels at that speed.

And all of this means that the light that left the Big Bang (or a moment after, once light actually started existing) is still out there.  It's always there.  It's always the-age-of-the-universe-in-light-years-away.

So all we really need to do is focus a telescope on 13.75 billion light-years, and bingo...a picture of the horizon of the Universe. (see left)

So it's no big deal, it's been done before.  A few people got the wrong end of the stick and called the picture "the face of God".  That's going a bit far whatever your views on theism, but if we're going to presume there is no god then this picture is the best we've got.  Sorry.  The point of science is we can do better.  Sure, the WMAP picture above is impressive, but the Planck satellite's first lot of data and scientific findings have been released, and they make WMAP look a little...well, what's a nice way to say obsolete with a huge amount of affection?

So here's a picture.  There's a lot of science in there, but for the moment just enjoy how pretty it is.

Image: ESA / Planck Project
Go on, click on it and revel in the full glory.  It's astoundingly beautiful.  That's a 360 degree image, of the entire Universe.

To be fair, there's a certain amount of interference.  All the blue stuff for example.  That's all hot dust, gas and various stars and stuff that's getting in the way...we call it the Milky Way, our galaxy.  The stuff beyond that is the really interesting bit, the orange/red bits to the top left and bottom right.  That's the real picture of the horizon, and there's going to be better to come once they get all that blue stuff out of the way.

And the weird oval shape?  Well that's an Aitoff projection, it's simply a way of showing the sphere of the Universe all around us, but on a 2D computer screen.

If you're really clever you write a program which wraps it onto a sphere and lets you fly around inside it, observing the Universe from the Planck satellite's own point of view.

If you're not quite that clever, like me, then you write the program but you can't correct for the pixel compression at the edge of the image, so there's a big belt of distortion around the middle.  And you can only make it work on Linux based computers so far.

Still, download it, give it a go, and give me a shout if it works, it's vaguely cool...
You'll need to change the permissions to make it executable ("chmod +x" or right-click the icon, properties, allow execution).

Controls:  Cursor keys plus A and Z for panning/rudder.