Moon Rockets

Interesting facts on the Saturn V rockets, from Wired’s Beauty and Madness of Sending a Man to the Moon

The fires on which it rose were not the fire that leaps or licks or plays, the fire of brasier or boiler. They were the focused fire of the metalworker’s torch, given life at a scale to cut worlds apart or weld them together. The temperature in the chambers was over 3,000°C (more than 5,000°F). The pressure was over 60 atmospheres. And still the pumps, their turbines spinning 90 times a second, were powerful enough to cram more and more oxygen and fuel into the inferno. The flames slammed into the fire pits below at six times the speed of sound. For a couple of minutes, the five F-1s generated almost 60 gigawatts of power. That is equivalent to the typical output of all Britain’s electric-power plants put together.

Looking at the generation statistics from Australia’s National Energy Market, our generation capacity in 2019 is only 46GW.

Part of making lunar-orbit rendezvous work was making the spacecraft that actually went down to the moon, the LM, as light as possible. In the original specification it was to weigh just 10 tonnes (11 tons). During development, it put on weight, despite furious attempts first to arrest and then to reverse the process. But it remained pretty tiny. And thanks to the need to carry fuel, oxidizer, life support, batteries, computers and more besides, the LM was noticeably smaller on the inside than the outside. The two astronauts had 4.7m3 (about 165 cubic feet) of pressurized volume between them. That is roughly twice the volume of one of London’s red telephone boxes.

Just goes to show how much energy is required to put such a small volume on the Moon, assuming of course that you want it to come back 🙂

Butterfly Effect

Clearing up a common misunderstanding of the Butterfly Effect

The only thing we can learn from the butterfly effect is that we cannot measure complex systems accurately enough to predict their behavior over the long term with enough precision. The big mismatch is that while the variation in ‘initial conditions’ is too small to measure, the variation in the outcomes is not.

Conspiracy Debunked
</param></param></param></embed>

A video which debunks the claims that the hacked CRU emails give evidence that claims of anthropogenic global warming are just a global conspiracy. Worth a watch.

Why Climate Debate Is Settled

DISCOVER magazine has uploaded the transcript of a recent panel on climate change they hosted in San Francisco, in conjunction with the National Science Foundation. The panellists explain in simple terms how we really know that it really is us humans causing the problem, and not natural processes.

Audience member: What is the most compelling evidence you have that human behavior is actually warming the planet?

Caldeira: To me the most compelling evidence is the fact that the stratosphere—the upper atmosphere—is cooling while the lower atmosphere and the land surface are warming. That’s a sign that greenhouse gases are trapping energy and keeping that energy close to the surface of the earth. I mentioned that in ocean acidification, you actually see animals that should make shells unable to make shells anymore. You could demonstrate the same kind of effect in a bell jar in the lab. There is a level of certainty about it.

One of the panellists, Stephen Schneider, addressed the question of anthropogenic causes as purely a statistical issue. Assuming we knew absolutely nothing about how the environment works…

If you were a cynic and you asked about the probability of the ice sheet in the north going up, it’s 50 percent. Going down? Fifty percent. And the South Pole going up? Fifty percent. Going down? Fifty percent. Probability they are both going together? Twenty-five percent. What’s the probability of the stratosphere cooling while the earth gets warmer? Again, assuming we knew nothing, 50 percent. Troposphere warming? Fifty. The probability that one will go up while the other goes down? Twenty-five percent. Same thing for other patterns, like the way high-latitude continents are warming more than low-latitude ones are. With any single line of evidence, you can say, “Oh, well, there’s still a 25 percent chance it’s random,” but what happens when you put all these events together? The probability of all these events’ lining up the same way is pretty darn low unless we are dealing with global warming.

Finally, the point about the debate being settled:

Caldeira: Climate science has reached the point that plate tectonics reached 30 years ago. It is the basic view of the vast majority of working scientists that human-induced climate change is real. There is a real diversity of informed opinion on how important climate change is going to be to various things that affect humans, and there is a diversity of opinion on how to address this problem, but the debate over human-induced climate change is over.

When asked whether they were optimistic about our ability to deal with the problem, Schneider replied

The first time I was asked that question in a public place was sometime in the 1970s in front of a congressional committee. My answer was a little bit like Ken’s. I said, “I’m technologically optimistic and politically bleak.” That proved to be a pretty good forecast for the next 35 years.

Unfortunately, it appears to be a good forecast for the next 35 years too. While I’ve no doubt we have the technical ability to fix this, I think we’re too stupid to get our shit together and actually do it. The general populace doesn’t understand science at all, so they’re largely incapable of critically evaluating the scientific evidence and coming to an informed decision.

You might expect the media to inform them, but the mass media is relatively useless too. In this era of newspaper cutbacks specialist science reporters are often discarded, leaving generalist reporters to write science articles, resulting in discredited anti-warming “science” being given equal time and giving their readership the impression that there still is a scientific debate on the topic.

Unfortunately, that leaves personal experience, and by the time the general populace realises they’re directly seeing the effects of global warming, it’s almost certainly too late.

Out-of-body Experiences

Researchers at the Karolinska Institutet have managed to convince people they are inside another person’s body, showing both how our sense of self is an emergent property of the brain, and also how tenuous it really is.

To create the illusion of occupying the dummy’s body, the team stroked the abdomen of the subject and the dummy at the same time while the subject watched the stroking via the cameras on the dummy’s head. As a result, subjects reported a strong feeling that the dummy’s body was their own. The technique is similar to the “rubber hand illusion”, in which a subject can be convinced that a rubber hand is his or her own, but this is the first time the illusion has been extended to a whole body.

The illusion was so convincing that when the researchers threatened the dummy with a knife they recorded an increase in the subject’s skin conductance response - the indicator of stress that polygraph lie detector tests rely on. “This shows how easy it is to change the brain’s perception of the physical self,” said Ehrsson, who led the project. “By manipulating sensory impressions, it’s possible to fool the self not only out of its body but into other bodies too.”

Things got even weirder when the researchers dispensed with the dummy and put the cameras on the head of another person. After carrying out the same double stroking routine the subjects were convinced that they were occupying another person’s body. The illusion persisted even when the other person came over and shook the subject’s hand, producing the sensation of the subject feeling as if they were shaking hands with themselves.

Overwhelming The Earth

One of the arguments of global warming deniers is that CO2 levels have been higher in the past than they are now, and that therefore it shouldn’t be a problem. Reuters has a good article which explains why this argument is false: it’s not really the absolute amount of CO2 that’s the problem, but the rate of change. We’re currently pumping CO2 into the atmosphere about 14,000 times faster than any stage in the last 600,000 years.

The average change in the amount of atmospheric carbon dioxide over the last 600,000 years has been just 22 parts per million by volume, Zeebe said, which means that 22 molecules of carbon dioxide were added to, or removed from, every million molecules of air.

Since the Industrial Revolution began in the 18th century, ushering in the widespread human use of fossil fuels, the amount of carbon dioxide in the atmosphere has risen by 100 parts per million.

That means human activities are putting carbon dioxide into the atmosphere about 14,000 times as fast as natural processes do, Zeebe said.

And it appears to be speeding up: the U.S. government reported last week that in 2007 alone, atmospheric carbon dioxide increased by 2.4 parts per million.

The natural mechanism will eventually absorb the excess carbon dioxide, Zeebe said, but not for hundreds of thousands of years.

The Descent Of Man

A couple of good articles this week have commented on the ramifications of Joe & Josephine Public’s lack of intellectual curiosity.

First up is David Colqhoun, whose article Science in an Age of Endarkenment was picked up by the Guardian Science site. He comments…

The enlightenment was a beautiful thing. People cast aside dogma and authority. They started to think for themselves. Natural science flourished. Understanding of the real world increased. The hegemony of religion slowly declined. Real universities were created and eventually democracy took hold. The modern world was born. Until recently we were making good progress. So what went wrong?

The past 30 years or so have been an age of endarkenment. It has been a period in which truth ceased to matter very much, and dogma and irrationality became once more respectable. This matters when people delude themselves into believing that we could be endangered at 45 minute’s notice by non-existent weapons of mass destruction.

It matters when reputable accountants delude themselves into thinking that Enron-style accounting is acceptable.

It matters when people are deluded into thinking that they will be rewarded in paradise for killing themselves and others.

It matters when bishops attribute floods to a deity whose evident vengefulness and malevolence leave one reeling. And it matters when science teachers start to believe that the earth was created 6000 years ago.

He then goes on to bemoan the increasing popularity of quack medicine such as homeopathy and crystals despite any hard evidence for their efficacy.

In a similar vein, Charles P. Pierce’s article in Esquire, entitled Greetings From Idiot America, was originally written back in 2005, but has even more relevance today. He tours through the nonsense surrounding creationism, and the onset of the Iraq War, while lambasting modern society for valuing gut instinct over fact and showing a willingness to believe what they’re told without applying any critical thought to the matter.

The rise of Idiot America is essentially a war on expertise. It’s not so much antimodernism or the distrust of intellectual elites that Richard Hofstadter deftly teased out of the national DNA forty years ago. Both of those things are part of it. However, the rise of Idiot America today represents — for profit mainly, but also, and more cynically, for political advantage and in the pursuit of power — the breakdown of a consensus that the pursuit of knowledge is a good. It also represents the ascendancy of the notion that the people whom we should trust the least are the people who best know what they’re talking about. In the new media age, everybody is a historian, or a preacher, or a scientist, or a sage. And if everyone is an expert, then nobody is, and the worst thing you can be in a society where everybody is an expert is, well, an actual expert.

Richard Dawkins also has a new documentary entitled Enemies of Reason which is now showing on Channel 4 in the UK. I’ve downloaded the torrent of the first episode to watch later tonight. Should be interesting. Beats the reality shite hands-down!

Monkey Business

Great article from the New York Times on what was learned from a study teaching capuchin monkeys to use money;

So, does Chen’s gambling experiment simply reveal the cognitive limitations of his small-brained subjects? Perhaps not. In similar experiments, it turns out that humans tend to make the same type of irrational decision at a nearly identical rate. Documenting this phenomenon, known as loss aversion, is what helped the psychologist Daniel Kahneman win a Nobel Prize in economics. The data generated by the capuchin monkeys, Chen says, ‘’make them statistically indistinguishable from most stock-market investors.’’

The full article is worth a read to discover the punch-line…

Gay Animals

The Oslo Natural History Museum has an exhibition on gay animals which is quite interesting. Homosexuality in the animal kingdom has been noted since Aristotle’s time (~300BC), but was usually dismissed as part of male fighting rituals. However, it has now been been documented in over 1500 species. Predictably, Christians aren’t too happy about it…

While the images displayed at the Natural History Museum wash over passing school children, the exhibition has sparked consternation in conservative Christians.

A Lutheran priest said he hoped the organisers would “burn in hell,” and a Pentecostal priest lashed out at the exhibition saying tax payers’ money used for it would have been better spent helping the animals correct “their perversions and deviances.”

I can’t stop laughing at that stupid priest trying to counsel animals! Father Doolittle ;-)

Bees

Carl Zimmer has a post entitled To Bee in which he covers the fact that the genome of the honeybee has been sequenced and 18 papers have just been published based on the results.

Just as striking is the low number of genes honeybees have for tasting. Insects have receptors on their tongues, known as gustatory genes. Honeybees have only 10 gustatory genes, compared to 68 in the fly. Again, the flower-grazing life of bees may account for this difference. Fruit flies and many other insects have an antagonistic relationship with plants. They devour the leaves and steams and seeds of the plants, depriving the plants of reproductive success. The plants have evolved lots of toxins in their tissues to repel the insects, driving the evolution of sophisticated taste in the insects so that they can avoid poisonous food. Bees, on the other hand, are in a friendly relationship with flowers, which depend on them to spread their pollen. Nectar lacks toxins altogether. Once a bee has settled on the right flower, it has little reason to fear the food it finds. And while many other insects must find food as larvae (think caterpillars munching tomato leaves), bees grow up in hives, delivered safe nectar by their aunts.