Archive for the ‘science’ Category
top gear heads south
The BBC TV show Top Gear has recently come in for some major criticism over a new “special”: a trip to the North Pole. The criticism has revolved around the environmental impact of driving three cars to the North Pole, especially if they leave their customary trail of parts behind them. If you haven’t seen the show, and don’t want to know what happened before you do, stop reading now: there are spoilers coming.
I’m prepared to overlook the environmental concerns, for the simple reason that the show is unlikely to inspire many more such jaunts: it was expensive, complex, and hardly easy on anyone involved, even those in the three cars. I came away with a general impression of “we did this, so you don’t have to, and we even got it on HD Video”.
After many scrapes, including one that required several parts and left a pool of diesel on the ice, the car with Clarkson and May got to the North Pole first, before Hammond’s dog sled (which he wasn’t driving). The truck needed a backup team of Icelanders to help them, who pulled off tricks such as re-inflating a tyre with a bottle of butane and a lighter. That’s alright, then isn’t it? It’s just TV, right? Not so fast.
I’m hardly a Geographic geek, but the shot of the truck arriving at the North Pole raised more questions. They showed the truck’s GPS screen hitting the mark: N78˚35’7” W104˚11’9”. The North Pole is at N90 latitude, of course, and all the Longitudes at once. What’s the difference? According to the Great Circle Mapper, the difference is 792 miles, or 1275 kilometers. You can see the positions on a map, here.
A-ha, I hear you saying: they must have gone to Magnetic North, then? Yes, I thought of that, but it still doesn’t add up: throughout the program, they always referred to the North Pole: no mention of the word “magnetic” that I can recall, though I could be wrong about that. There’s another problem: they didn’t actually go the North Magnetic Pole.
The latest coordinates I can find for the location of the North Magnetic Pole are those from 2005, which were estimated at 82.7°’N 114°4′W. This is quite a long way from the show’s “North Pole” location: 307 miles, to be exact, according to another Great Circle Map. To be fair, however, the North Magnetic Pole has been near the location they used in the show: in 1994, according to the this map and other historical figures I looked up.
How does that compare to how far they actually went? They started at Resolute, in Nunavut, which is at 74°41′40.27″N 94°50′23.64″W. I know they didn’t go in a straight line, but if they had, another Great Circle Map tells me how far the crow flew: 308 miles.
In other words: their trip to the North Pole took them almost exactly halfway to the North Magnetic Pole. Come on, Jeremy: care to talk your way out of this one? If you were following the 2007 Polar Race route, you didn’t say anything about that…
plane thinking
At the beginning of 2006 I speculated that I would be doing less travelling. That suited me, simply out of general consideration for the environment. I didn’t need news headlines , or the European Union, to tell me that air travel is not good for it. So, I imagined, 2006 would be a quieter year for me, with fewer flights.
The reality turned out to be very different:
- April = 4 flights: Dublin <-> London, Dublin <-> Lisbon
- May = 1 flight: Dublin -> Copenhagen
- June = 5 flights: Copenhagen -> Dublin, Dublin <-> Amsterdam <-> Lyon
- July = 2 flights: Dublin <-> London
- November = 2 flights: Dublin <-> London
- December = 4 flights: Dublin <-> Dubai <-> Bangalore
That makes eighteen (18) flights in one year; eight of those for work-related reasons, the other ten for no good reason. By way of comparison, I calculate that I took nine (9) flights, half this year’s tally, in my first 25 years. Must do better this year – the environment needs me to cut back on the flying!
Besides, the romance has gone: RyanAir is working hard to make flying as exciting as taking a bus, and even though I didn’t fly with them last year, Aer Lingus are not that far behind, out of competitive pressures. I think I’ll take the ferry next time I visit the UK.
conveyor belt plane
I didn’t want to do it, honest, but I have really had enough of the “plane on a conveyor belt” myth, so I’m posting my take on the problem here. I’m using the kind of title that search engines will like, and I can point other people, on other forums, to this response.
The basic question goes something like this: if you could put a plane, of any size, on a conveyor belt, will it take off? The conveyor belt speeds up to match the plane’s exact speed, keeping it stationary, so it can’t move forward, right?
The question is framed badly – a bit like an “irresistible force vs. immovable object”. The first key point, which most people get, is that the engines are pushing against the air, not driving the wheels, which spin freely with a small amount of friction. This should make the answer easy, if you think in terms of Forces: the plane is trying to move forward, what would hold it back? Not friction – far too small a force. The plane moves forward, and eventually takes off, regardless of whatever the belt is doing.
Not enough? Well, what can the belt do, anyway? Another fundamental problem lies in the idea of the conveyor matching the plane’s speed. How would such a control system work?
- measure the plane’s speed
- speed up the belt to match the speed of the plane
- GOTO 1
Steps 1 and 2 both take time.
- All forms of speed measurement mechanism have an inherent time delay. If you doubt this, go back to the fundamental definition of what speed is: distance over time. This is even true of high-frequency speed measurement systems such as Doppler Radar or Lidar, as used by law enforcement.
Another way of looking at it: if you could take a zero-time snapshot of any object at any speed, it would always appear to be standing still (velocity=0), making that useless for velocity measurement: you need time to measure the distance travelled. - If the conveyor has any mass, it can not change speed instantaneously. That would require infinite acceleration of its mass, meaning an infinite force would be needed (since force = mass x acceleration). Anything less, there’s a time delay. Don’t believe me? Try putting the figures in to the basic Newtonian acceleration formula, A = ΔV / T , where A = acceleration, ΔV = the change in velocity, and T = time = 0. Oh, and before you invoke Einstein, be aware that his Relativity formulae do not contradict Newton’s at these non-relativistic velocities.
- With these inherent time delays in the control system: by the time the conveyor reaches its intended speed, the plane has accelerated to a new speed, so the conyeyor is slower than the plane, which is thus moving forward! Repeat until V0, V1, and Vr (takeoff).
Other references:
- kottke.org
- Pogue’s Blog (NY Times)
- videos on YouTube: 1, 2
Can I go now?
idiocracy and devolution
For years I’ve been a little worried about a demographic trend that has the potential to stop “positive evolution” in its tracks. By “positive evolution” I mean the idea that evolution leads to better, smarter people. Perhaps it’s considered elitist to wish for such a thing, and I know that assuming it would be a fallacy, but one may hope, may one not? After all, we don’t have another life to look forward to, so it’s natural for me to wish for more from this one.
I’m hardly the first to wonder where the human race is heading – as any Devo fan will know – but the trend that worries me is the falling birth rate in the developed countries in general, and among the most intelligent and educated sections of society in particular.
Unfortunately, in the absence of education and intelligence, it’s back to “survival of the fittest”, in my estimation. Today that seems to mean “breed like bunnies”. In poor countries this seems to imply “have many children, because some will die, and who will look after you in your old age?”. In the lower demographic strata of Western societies, especially Europe, this is read as “have many children, because the government will pay you and do what you can’t do for them”. I won’t get in to the politics, but this is compounded by poor education and awareness of family planning, which religion sometimes plays a part in. The Catholic ban on contraception is the obvious example here.
I keep in touch with various people I’ve met over the years: many of them are not married, and those who are have families of one or two children. One friend has a third on the way, which is very much the exception. I’m not exactly “high class”, whatever that is, but my acquaintances are all professional, working people, the “salt of the earth”.
Compare and contrast that with the poorer countries of the world, and the less-educated parts of the developed countries: Africa, Central America, the US South. I was shocked to see the 2005 statistics for Afghanistan, which had a birth rate of 46.6 per 1000 per year, and a 20 per 1000 death rate, that still leaves them which a 2.67% growth rate. I have all the stats in a spreadsheet, so I can sort them by the different factors, and they make sobering reading. The poorest countries – nearly all in Africa – are growing the fastest, thwarting any attempts to improve their living standards.
In the USA, this trend has not gone unnoticed by Mike Judge, creator of Beavis and Butthead and Office Space, whose new film Idiocracy was belatedly “dumped” in US cinemas and has not made it to Europe yet, if it ever does. It imagines an ordinary man who spends 500 years in stasis, and emerges in to a world that has gone downhill, intellectually, leaving him the smartest person in it by far.
In my view, even if things don’t go all the way down that road, we are still facing a “cap” on the intelligence of the human race: with the smartest people the best at reading the signs all around them and having small families, while the lumpenproletariat* think only of their short-term needs and desires, and not about how their world will be affected by their profligacy.
I am well aware that talk of “improving the human race” carries all sort of negative connotations, from elitism to eugenics, and I’m not suggesting any kind of direct intervention in what I perceive as a negative trend. However, what strikes me as most relevant to this forum is the way organized religion prevents individual people from realizing their potential in many different ways. Wilful ignorance of leaders, obstructions to family planning initiatives, education sabotaged by religious beliefs… those are the areas where I hope Prof. Dawkins’ book can make a difference, perhaps eventually proving me wrong!
* I’m kidding! Please stop hitting me with copies of Das Kapital!
thank who for Velcro®?
Much as I enjoy and appreciate Anousheh Ansari’s groundbreaking (?) blog from the International Space Station the title of one entry distracted a little from the contents: Thank God for Velcro. Velcro®, after all is purely man-made, with nothing religious about it. Sure, it was inspired by nature, but nature is hardly a spiritual place, except when viewed from perspectives particular to some members of the human race. Of course I know what she meant, but it’s a little odd.
It’s only a tiny distraction; Ms. Ansari’s writing gives me that “wish you were here” feeling, and I really wish I was, despite some of the privations she describes. I would be tempted to spend hours staring out the window at the Earth turning beneath me. I had imagined it would be “all go” up there, with the cosmonauts taking as little sleep as they could get away with, but that’s not sustainable over an extended stay up there, so it makes sense for them to pace themselves.
Sadly, my eyesight alone will ensure that I never see space in this lifetime. Even if I have laser surgery to correct my vision, the shape of my eyes means that I will remain vulnerable to a detached retina if I am ever subjected to high G-forces. Never mind: I can live vicariously through blogs such as Ms. Ansari’s.
global warning
Finally: some scientists are looking beyond ways of slowing down or stopping global warming, and are starting to address the questions of how humanity will cope. I’ve asked, in these pages, why people continue to build their homes in low-lying areas that are subject to flooding, when a little geographic knowledge will let them understand just how dangerous it is.
In most cases, of course, people do not have much of a choice: they need to be somewhere, within the borders of their country, and when their country is e.g. Bangladesh – most of the country less than 10 metres above sea level – they can assume they will be affected by floods even before global warming kicks in. A sea level rise of just one metre will submerge an estimated 10% of Bangladesh – already one of the most densely-populated countries in the world.
Once again, we come back to the question of population: people producing more children than their country can support. It doesn’t make sense even at this time, far less if you are to look at the known problems facing any particular country in the future. Once again I find myself saying: if people don’t take care of themselves and their futures, by planning their families, Mother Nature will take care of them.
colour blandness
I just took two quick tests on colorvisiontesting.com, along with a colleague; while I have doubts about such tests, because of the variability of computer monitors, these ones gave a clear result, confirming that I’m colour-blind relative to “normal” people.
I would never have known I was severely colour-blind if not for the Ishihara tests, which I took under medical supervision years ago. One translation of Ishihara (石原) might be “stony wilderness”, which (I suppose) describes where the Cones should be in my retinas; I hope that means more Rods, since I do think I have good night vision. Apart from that, the only effect visible to me, outside the tests, is difficulty distinguishing between similar colours in poor light – which I thought everyone had problems with.
I took a more thorough test, a few years ago, in the research department of the Royal Victoria Eye Hospital here in Dublin. (An Irish institution named after an English Queen, with the Royal prefix? Hey, if it ain’t broke…) It involved laying little pots of colour in order, e.g. from blue to red. Didn’t do too well there either, if the tut-tutting of the researcher was any clue. (I admit to being slightly distracted by the researcher, who was named Hilary, and was rather beautiful in a slightly Lilith Sternin Crane fashion.)
So, if I’m colour-blind… what am I doing learning photography? Or should I stick to black-and-white film? I find some software colour correction of digital images to be overactive, but I think I have to trust it, at least on pictures aimed at this site.
No, it’s not spelled “color”. I don’t mind using some American spellings, particularly those where a “s” is replaced with a “z” (e.g. “realize”), since I think the change aids in correct pronunciation, but this one is a little beyond the pale (pun intended)…
makebots
I went to the Artbots 2005 exhibition yesterday. It was the last day, by which time the robots, and the artists, were a little frayed around the edges. I tried to ask one of them about the circuit bending nature of his work – randomly short-circuiting the RAM on a PC’s video card – but he’d clearly had enough, didn’t know what I meant and could hardly care. Other exhibits were broken or malfunctioning, or absent.
It was fun to see how few of the exhibits were actually robotic, and were more electronic in nature. Is it robotic if there is no feedback mechanism, if you are simply controlling motors from a PC? The results can be interesting, but I wouldn’t call that robotic. One good example of how it can be was the robot that drew pictures on the wall, such as a field of grass.
The workshops for kids were in full swing, with a MIDI workshop sending random bleeps and piano hits through the air. It’s great to get kids building, and there’s a related project for adults too: Make magazine, which I would get if postage wasn’t so expensive. I’ll have to make do, pardon the pun, with the Make Blog feeds in my RSS reader.
eternal sunburn of the witless mind
Part II of the Paris Air Show report: before I get to the planes and the flight displays, a little about the airfield and the facilities. All the general public spectators were crammed into a small section of the flight line – the area closest to the runway – though there was more space further back. I arrived not long before the flight display was due to start, so I went straight to the flight line and spent most of the afternoon there, taking pictures.
It was a very hot day, with almost no shade, and the organizers broadcasting warnings to everyone to drink plenty of water. Could you get water? At a price. A baguette (sub) with jambon et fromage (ham & cheese), a 500ml bottle of Coke, and a 500ml bottle of water came to €12 ($15), more than double the typical street price.
The displays had an element of unreality to them: the Airbus A380-800 was parked just in front of us, the last in a row of three Airbuses taking part. First the little A318, then the incredibly long A340-600. This thing just kept on going, long past the point where other planes would have stopped. Landing it must be a hair-raising exercise in centre-of-gravity and airspeed control.
The A380-800 is shorter, but its sheer bulk makes it the first plane to have a takeoff weight in excess of a million pounds (454 tonnes). The test pilots kept its flight display relatively sedate – it’s maiden flight was only a month ago, after all – and they didn’t even raise the gear, saying it takes 30 seconds of level flight to accomplish that. (It would have been halfway to Versailles in 30 seconds.) I didn’t get a good view of any of the landings, which was a disappoinment, seeing as the landing is the most crucial part of any flight.
After an hour I was fried, after two hours I was grilled, and after three I was roasted. By 4PM I decided I needed to get out of there. On the way to the hotel, however… describing this scene is going to stretch my descriptive vocabularly somewhat.
- A veritable cornucopia of hot, tired, sweaty people, stacked 42-deep around the bus stops, and the show is not quite over. I couldn’t even see which queue I should join, not that I had a chance of getting the bus, so I joined the hordes slogging their way back to Le Bourget station.
- At each intersection was a large, angry gendarme, clearly unhappy about spending his Saturday directing traffic and pedestrians. Loud whistles, heated disputation, wild gesticulation, oh my.
- Two kilometres later, I arrived at the station to find the masses wending its way inwards. As far as I could tell, tickets were optional, with a sign telling people to buy €2 tickets for central Paris, and nothing else.
- Hot, bothered, and distracted by all the commotion, I neglected to look where I was going and fell over a tree emplantation, so my right ankle is now in a state somewhere between “twisted” and “sprained” Cue much Anglo-Saxon swearing and quizzical looks from the locals. (A week later, considering how slowly it’s healing, I call it a mild sprain.)
- Since I’m heading north, I limp straight through the gates on to the platform, and am mildly surprised to find I made the right choice, and could get on the right train when it arrived.
- Whew, right? Not quite. I know I’m going to Villepinte, so I get off at the Villepinte station, before I remember not to do that. It’s a 1/2 hour wait for the next train, sadly, before I can head for the right station, Parc D’Expositions. Walking was not an option, with my painful ankle swelling up.
- A hotel that was supposed to be quite close to that station turned out to be quite far, and I had to pull into another hotel for directions first. I must have looked a fright, but I at least got them to give me some cold water too. This other hotel was really close to the station, so guess where I’m staying next time, expense be damnedm if there is a next time.
- The hotel I chose this time was really inexpensive, but was a painful half kilometer from the station. It was OK for one night, any longer and would I have sleep-walked my way out the window. It had some semi-permanent residents, welfare cases who put on a classic “white trash” performance for my benefit – heated arguments about money at 2am.
To add insult to injury; I managed to drop my iPaq later that evening. All my contact and appointment data was wiped after the battery came out, but at least it’s all on my home PC and work PC too. I don’t need any of that in my hand until I go back to work, and it can still play MP3s etc. I even took this opportunity to try Linux on it, which is also data-destructive. (Call it a work in progress.)
A week later, and the skin on my arms is still coming off in clumps, and I’m very red in the face. In my concern to get decent photographs, I neglected to carry a hat or sunscreen, didn’t I?
The holiday is almost over, and it’s back to work on Monday, at which point I’ll find out whether my trip to Germany is still on, or not. If so, it’s not back to regular work directly, and I have to prepare to deliver product training. The most flattering part, so far, has been hearing what my department will be charging for my services. That’s per day, multiplied by three days of training plus a day for travel and a day for preparation, plus costs for travel and expenses. (But it’s still much less than trying to buy this training from an external provider.)
a flight of fancy
Well, that was fun. I’m getting much better at finding my way around places, compared to a decade ago. I got up early and left home at 04:15 or so, thinking the bus to the airport would arrive at 04:30 at advertised. It arrived at 04:20, about a minute after I arrived at the bus stop, and was surprisingly full for that time of the morning. Some check-ins at the airport were mobbed at 05:00, with people queueing around the terminal for cheap holiday flights, though my check-in was no problem.
The flight boarded on time, but left about half-an-hour late, and the excuse was a new one on me: “we have a wide departure window”. Meaning… what exactly? That the tower gave you a wide time window, in which case you gave no excuse for leaving late in that window… or that the airline decided they could afford to be slack at that time of the morning… which is also no excuse. At least they served a nice little continental breakfast, different each way, which was even more welcome on the way home.
This was my first visit to Charles de Gaulle airport, north of Paris, and quite an experience it was too. Let me see… if you’ve seen U2’s “Beautiful Day” video you have a general idea of what Terminal 2 looks like, but not the scale of the place. It contains six medium-sized terminals under one huge roof, A-F, an overall size roughly equivalent to Heathrow Terminal 1, 2 and 3 combined or Chicago O’Hare International. Terminal 1 is a separate huge building of its own.
I landed at Terminal 2F, and after a bus ride to the Terminal proper I had to take one of the walkways to the central area of the Terminal, where the RER station was. One of those walkways collapsed just over a year ago, killing six people, and that area is still cordoned off.
This is the point at which I ran head-first into Paris’, well … interesting transport system:
- Try to catch the advertised bus from the airport to the Air Show? The information desk said to go to the bus stop at the RER station, which was what I remembered. No show – no bus turned up in 3/4 of an hour, no signs anywhere, no hint of a schedule.
- OK, back to Plan A: the train. Should be simple… until you try to buy a ticket:
- Ticket office? Not for the RER (suburban railway), only machines. Machines that don’t take notes, only coins and cards.
- The machines are running OS/2 Warp – old – and in French only. (I later found a machine in a remote suburb of Paris that did have an English mode, but putting some of those at an International Airport would make too much sense, of course.)
- That’s manageable, because I have enough French vocabularly to get by.
- The thing was: of about eight machines in the station, only two were working. The hedgehogged ones had “fixed by July” signs on them, and the working ones had huge queues behind them.
- I resigned myself to joining the back of the queue at one machine… the screen of which was stuck with an inscrutable message… then it rebooted. The rest of the queue started swearing, in a multitude of languages, then wandered off to the other queue leaving me in front.
- Great: after an extended self-test the machine was running again, and I could see how to buy a single to Le Bourget. No notes accepted, no coins in my wallet, so a card it had to be. I tried three different cards, and each was refused; carte non acceptee. This process was interrupted by concerned queries from those behind me: “is it working? taking the card? what card is that?”
- No luck, I thought, and turned to walk away, but someone stopped me in time: it had worked, it just hadn’t told me clearly.
- The train was there, and I made it on board just before it left. At Le Bourget station the shuttle buses were filling up, but I was on one in ten minutes, and at the airfield in ten more. Whew.
I’ll write about the Paris Air Show proper next, but here’s a teaser: the star of the show, the Airbus A380-800 a.k.a. the flying ocean liner.
a wind over the world
Oh, for a fat pipe at home. No, not a blunt green one, I mean a fat Internet pipe. I appear to have found my “killer app”: NASA World Wind. This is a program for viewing satellite imagery from different sources, and it’s all free.
Today (and yesterday) I had my laptop at work, occasionally viewing parts of the world. The way it works is: you start off with a fairly detailed globe, and zoom in on any part you like. Depending on the part of the world you’re looking at, the available detail varies, with rural or wild areas having the least detail, the USA having more, and then there’s the USGS Urban Area Orthographic data. This has some shockingly detailed images of US Cities: never mind “I can see my house”, more like “I can see your bald spot”. It also contains elevation data, and you can tilt the viewpoint to give a realistic 3D view of the scene.
There is also the “Rapid Fire MODIS” function, which lets you look up selected imagery of events, ranging from phytoplankton blooms to dust storms, fires and hurricanes. Some amazing shots, such as sand from the Sahara getting just about everywhere in that hemisphere.
Speaking of bald spots: I finally ditched the hippie look last Saturday. I have no idea what a good hairstyle for me would be, so I got something acceptable by telling the barber what I didn’t want:
- not bald, or short-back-and-sides: I want to keep some length overall. The skinhead look appears to be “the norm” where I work, and I’m not buying it. Where’s the fun in that?
- no hair in my eyes. I even tried gel to help with that problem, but it didn’t last, so I ended up with congealed logs of hair in my eyes;
- no, no, no! Not a Mullet! I don’t mind losing the long back, if I avoid that particular pitfall.
The result can be called a civilized rock star look, with short “bangs”, some top, and a medium-length back. Boring, I suppose, but I can’t see it unless I look in a mirror, and it’s not often I do that.
Saturday was another of those “good days” I’ve written about before. Technically, it started on Friday evening, when I arrived home to find the camera parts I ordered, but I did the repair in daylight the next day. It was slightly fiddly, I had to use a found screw in one position (since I lost the original and none were supplied), but that was enough of a hassle to make the succesful result all-the-more satisfying. My camera is whole again, with almost no visible damage, and I don’t have to remove half the bottom screws to replace the batteries any more.
What do you do with a good mood? You ride it over normally unpleasant tasks, like housekeeping, so I got out the vacuum cleaner, etcetera. Then shopping, a meeting with friends for drinks, then finally a late movie: Kikujiro. Slow, but rewarding: I ended up recording it, and watching the last third the next day. I had to call it a day, and a Day it certainly was, with a capital D.
a policy of uncertainty
On Spiked Science there is a series of quotes from various scientists, answering the question: “if you could teach the world just one thing…”
I should teach the world that science is the art of doubt, not of certainty. Science is the antithesis of faith, and of the popular view that science provides immutable theories and fixed facts about the world in which we live.
– Frances M Ashcroft
If I could teach the world just one thing about science, then it would be how to think about the world and ourselves in the sceptical, evidence- and model-based manner. That is the main contribution of science, and is perhaps the greatest invention in human history.
– Alan M Kay
I should teach the world that science as the search for answers actually generates only more questions, and as a result, the amount of knowledge available to humankind continues to grow exponentially.
This is of no great value, however, unless we also develop systems of understanding to assimilate and act upon this information effectively, to prioritise it and understand its value, and to inform our decisions, drawing upon the diverse origins of the data in a consistent way. What we need to focus on, in the coming decades, is the development of wisdom systems – that is, our ability to use knowledge effectively, for the benefit of people and the environment around us.
– Dr Bob Bloomfield
The main thing to understand is that science is about uncertainty. Science teaches us to have a high tolerance of uncertainty. We do not yet know the answers to most of the important questions – nature is smarter than we are. But if we are patient, and not in too much of a hurry, then science gives us a good way to find the answers.
– Freeman J Dyson
I couldn’t have said it better myself.
Addendum: a short article by Salman Rushdie, reprinted on Beyond The Beyond, Bruce Sterling’s Wired Blog: The Trouble With Religion.









