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Peter Nixon
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Saturday, 31 August 2002
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Friday, 30 August 2002
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Thursday, 29 August 2002
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Tuesday, 27 August 2002
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Kato, the cycling son has just been to the doctor. He's been getting intense cramps and has found it hard to finish races lately; this after glandular fever and a serious argument with a car that put him out of action for months, and a couple of minor prangs since.
He has a drug to take, some extreme stretches and an appointment with a podiatrist. He may need orthotics.
6:46:16 PM 
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Hmmm, not a lot happening.
6:41:14 PM
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Saturday, 24 August 2002
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Here is an interesting article about the Mac making inroads among the scientific community. It's a little gung-ho, but I can take that.
5:02:29 PM
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How the planets got their stripes. Stripes observed on the disks of gaseous giant planets (Jupiter, Saturn, Uranus and Neptune) are formed by trains of clouds transported by organized, steady atmospheric currents. Typically, atmospheric turbulence would break the clouds down into smaller and smaller features until no large features were visible. However, in thin atmospheres the effect is opposite. The rotation of the planets combines with the turbulence to create the large-scale structures we see as rings, stripes and spots.
This paper is due to appear in Physical Review Letters in the September 16 print issue.
(From my Physics Tip Sheet)
The semi-technical version
This text was written for us at the American Physical Society by the authors of the research paper.
Stripes observed on the disks of gaseous giant planets (Jupiter, Saturn, Uranus and Neptune) are formed by trains of clouds transported by organized, steady atmospheric currents. There are no obvious energy sources sustaining such circulation. Kinetic energy introduced on smaller scales is expected to be dissipated by chaotic turbulent motion rather than contributing to the highly organized large-scale circulation.
What factors sustain that circulation? Typically, turbulent motion features large vortices that break down to smaller and smaller ones (direct energy cascade) until the smallest of them dissipate by the action of molecular viscosity. In thin planetary atmospheres, however, the dynamics is completely different. Turbulence gains very peculiar properties; instead of dissipating energy, it transfers it to large-scale flow configurations giving rise to inverse energy cascade.
The rate of vertical rotation on spherical planets changes with latitude (the so-called beta-effect) giving rise to planetary (or Rossby) waves and rendering the inverse cascade even more peculiar. Due to the intricacy of interaction between turbulence and Rossby waves, the inverse energy cascade becomes redirected into alternating, very steady latitudinal (zonal) jets that contain most of the energy of the large-scale circulation. These jets trap the clouds and appear as the stripes on the planetary disks.
The physical mechanisms that cause the emergence of the jets and regulate their behavior have long remained a mystery. This research has identified the physical law that governs the behavior of two-dimensional turbulence with a variable rate of rotation and has given it mathematical quantification. This law relates the energy level in every spatial component to such basic planetary parameters as the planet's radius and the angular velocity of rotation. Using this law, we have developed simple relationships between various flow characteristics. Surprisingly, we found that the total kinetic energy of the planetary circulation depends not on the rate of energy supply to the atmosphere but on the rate of energy dissipation. If the dissipation is small, even a minuscule forcing can spin up a very strong circulation over a long time.
Assuming that colder planets (those farther away from the Sun) have smaller dissipation due to weaker thermal activity, our research explains why the giant planets' atmospheres reveal increasing intensity of circulation the farther they are from the Sun. Neptune, the farthest giant planet away from the Sun, proves this point by having the strongest circulation in the Solar system. The new law is of fundamental importance not only in the theory of two-dimensional turbulence but also in atmospheric sciences and planetology. The results explain some of the fascinating features of atmospheric circulations on gaseous giant planets. The importance of these results is further underscored by their universality. When appropriate data becomes available, the new theory can be applied to gain insight into the atmospheric circulation on extra-solar giant planets and obtain quantitative information on the basic features and energetics of these circulations. [David Harris: Science news]
1:58:02 AM
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Friday, 23 August 2002
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Mahatma Gandhi. "In the attitude of silence the soul finds the path in an clearer light, and what is elusive and deceptive resolves itself into crystal clearness. Our life is a long and arduous quest after Truth." [Rick@Leaders.net: Quotes]
1:09:32 AM
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Thursday, 22 August 2002
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Pluto cooling update. You read about Pluto cooling here five days ago here but CNN just picked it up today... Curiously, the CNN take on the topic is that Pluto is experiencing global warming whereas the press release from the observatory (and my interpretation of the results) says that Pluto is going through a cooling. It is possible that the surface may be warming slightly but does that justify reversing the meaning of the headline? Strange.
[David Harris: Science news]
1:48:36 AM
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Understanding risk. One of my pet hates is the extreme irrationality of people when faced with certain risks. Yes, I know the fears are understandable, it's just that it bugs me that in a world where we have so much information available to us, we can't seem to make decisions based on anything more than gut instincts...
Part of breaking down irrationality would seem to require some basic information concerning why people worry about particular things. Today's New York Times (free registration required) has a nice piece that outlines some of the main reasons for worry and gives examples of how people react.
After you've read the piece, think about how many government policy decisions seem to be based on irrational fears. But we can't just blame a government - we are all far too ready to look for a scapegoat for any problem or risk. Instead, we must consider how our opinions about risk are driving government policy decisions. As a simple example, there is incontrovertible evidence that many lives would be saved if everybody wore seatbelts in cars yet governments in some jurisdictions won't enforce it by law because of public pressure against it. [David Harris: Science news]
1:45:24 AM
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12,000 frames per second film camera. The new tool film-makers will go crazy over can shoot the equivalent of 12,000 frames per second. Unfortunately, the camera can only shoot 120 frames at a time as it works by rotating a loop of film around a drum that rapidly revolves.
Just as The Matrix popularised the use of sequenced still cameras to give the impression of a fast-moving camera circling around a subject, don't be surprised if you suddenly see lots of films breaking into ultra-slow motion for a few seconds as they insert the results of this new toy.
The camera is bound to be useful for other things besides entertainment. Just as it is based on high-speed scientific photography, this technology or something similar will probably make it back into the lab where high-resolution is required as well as high-speed.
Read more and see a sample at CNN (Sample requires CNN realplayer media pass) [David Harris: Science news]
1:41:01 AM
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Global cooling... on Pluto!
Apparently, Pluto's climate has changed drastically since the last time people looked 14 years ago. The atmosphere is cooling but the surface seems to be warming.
Astronomers are currently unable to determine the reasons for the changes but hope that the planned Pluto-Kuiper Belt mission launching in 2006 and arriving at Pluto in 2016 will help answer their questions. [David Harris: Science news]
1:35:28 AM
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Tuesday, 20 August 2002
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I've been reading the History of the telephone, as written in 1910 by Herberst Casson. It has been very refreshing to read how hard it was for Bell to get anyone to notice, look ar listen to his new device. In fact, it wasn't until he sent a 'news story' at a distance of 16 miles, that he received the attention he needed: the press. Seems they only react when their own business affected.
So much of this story is analogous to weblogs. Their invention, mis(understanding) and application all pretty much went through the same stages. Here's one you'll recognize:
"There were hundreds of shrewd capitalists in American cities in 1876, looking with sharp eyes in all directions for business chances; but not one of them came to Bell with an offer to buy his patent. Not one came running for a State contract. And neither did any legislature, or city council, come forward to the task of giving the people a cheap and efficient telephone service."
It gets better: " ......it was a most unpropitious time for the setting afloat of a new enterprise. It was a period of turmoil and suspicion. What with the Jay Cooke failure, the Hayes-Tilden deadlock, and the bursting of a hundred railroad bubbles, there was very little in the news of the day to encourage investors." [Adam Curry: Adam Curry's Weblog]
11:34:07 PM
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Understanding risk
One of my pet hates is the extreme irrationality of people when faced with certain risks. Yes, I know the fears are understandable, it's just that it bugs me that in a world where we have so much information available to us, we can't seem to make decisions based on anything more than gut instincts...
Part of breaking down irrationality would seem to require some basic information concerning why people worry about particular things. Today's New York Times (free registration required) has a nice piece that outlines some of the main reasons for worry and gives examples of how people react.
After you've read the piece, think about how many government policy decisions seem to be based on irrational fears. But we can't just blame a government - we are all far too ready to look for a scapegoat for any problem or risk. Instead, we must consider how our opinions about risk are driving government policy decisions. As a simple example, there is incontrovertible evidence that many lives would be saved if everybody wore seatbelts in cars yet governments in some jurisdictions won't enforce it by law because of public pressure against it. [David Harris: Science news]
11:33:04 PM
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12,000 frames per second film camera
The new tool film-makers will go crazy over can shoot the equivalent of 12,000 frames per second. Unfortunately, the camera can only shoot 120 frames at a time as it works by rotating a loop of film around a drum that rapidly revolves.
Just as The Matrix popularised the use of sequenced still cameras to give the impression of a fast-moving camera circling around a subject, don't be surprised if you suddenly see lots of films breaking into ultra-slow motion for a few seconds as they insert the results of this new toy.
The camera is bound to be useful for other things besides entertainment. Just as it is based on high-speed scientific photography, this technology or something similar will probably make it back into the lab where high-resolution is required as well as high-speed.
Read more and see a sample at CNN (Sample requires CNN realplayer media pass) [David Harris: Science news]
11:30:04 PM
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Euripides. "The best and safest thing is to keep a balance in your life, acknowledge the great powers around us and in us. If you can do that, and live that way, you are really a wise man."
Pearl Buck. "Inside myself is a place where I live all alone and that's where you renew your springs that never dry up." [Rick@Leaders.net: Quotes]
11:28:18 PM
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Today is.... 1930: Phil Farnsworth awarded a patent for television
1960: Russian dogs Belka and Strelka return from space
1977: Launch of Voyager 2 [David Harris: Science news]
11:13:52 PM
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Contour spacecraft update
The BBC and CNN report that the Contour comet-hunting spacecraftf may have broken in two after a rocket malfunction.
[David Harris: Science news]
10:25:11 PM
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Monday, 19 August 2002
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I've just created my first category.
Radio allows for kind of interest areas called categories.
It's very cool, but like everything in Radio there are some bits and pieces that are not obvious.
I'm very pleased that I have been able to create a category called "cycling" (look left) in which I can focus on cycling stuff such as the Tour de France
and also brag about my own son, Kato Nixon's achievements.
1:05:06 AM
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Kato raced on the weekend. He has had health and injury problems for two years.
As the bunch turned into the final turn on the last of seven laps on a hilly course there was a fall. I saw the fall but it was a long way from the finish line where I was. I just knew it was him.
I watched rider after rider come home - no Kato.
So he limped in. Yes he had been hit from behind and had fallen.
He has been so unlucky.
We did the right thing and hung around for the prize presentations.
A pleasant surprise was that this particular race had a strongest rider prize awarded by the commissaires, and Kato won that. He had been riding well and attacking often.
12:24:33 AM
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Sunday, 18 August 2002
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From the Baltimore Chronicle: "Go get your ten-billionth burger, America. Fatten your already fat asses with bacteria-and-hormone-ridden meat and do nothing as you sit stupefied before your mind-numbing television sets awaiting the next episode of sad families being humiliated on "Cops."
This article was published over a week ago, but I hadn't heard of, or seen it yet. If only 10% of it is true, then we should be very afraid. Deep in my gut, I feel W.R. McDougall has hit it all squarely on the nose. Time for action America! [Adam Curry: Adam Curry's Weblog]
11:57:30 PM
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Elie Wiesel. "Ultimately, the only power to which man should aspire is that which he exercises over himself."
Hippocrates. "Walking is man's best medicine." [Rick@Leaders.net: Quotes]
1:13:35 AM
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Saturday, 17 August 2002
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Here is "Another test, this time for a comments link" which I am pretty sure works.
Hooray for Radio!
1:39:08 AM
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Global cooling... on Pluto!
Apparently, Pluto's climate has changed drastically since the last time people looked 14 years ago. The atmosphere is cooling but the surface seems to be warming.
Astronomers are currently unable to determine the reasons for the changes but hope that the planned Pluto-Kuiper Belt mission launching in 2006 and arriving at Pluto in 2016 will help answer their questions. [David Harris: Science news]
1:09:37 AM
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Friday, 16 August 2002
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Today is ...
1892: Birth of Louis-Victor de Broglie, physicist known for his discovery of the wave nature of electrons
1914: Panama canal opened
1877: Thomas Edison coined the telephone greeting "Hello"
[David Harris: Science news]
9:28:42 AM
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Thursday, 15 August 2002
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I've made my first attempt, "just a test", at building what Radio calls a story.
It seems to be a web page that is not part of the log.
10:59:05 PM
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Today is ...
1777: Birth of Hans Christian Ørsted, physicist who discovered that electric current in a wire can deflect a magnetized compass needle
1886: Birth of Arthur Jeffrey Dempster, physicist who built the first mass spectrometer
1994: Hubble space telescope took pictures of the rings of Uranus [David Harris: Science news]
10:51:01 PM
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Silkworm silk can match spider silk for strength
Silkworm silk has generally been seen as weaker then the silk from spiders. However, much depends on the preparation of the silkworm silk, especially how it is spun.
By spinning silk at different speeds, it can be given different properties according to a paper to appear in tomorrow's Nature. Faster spinning creates stronger more brittle fibres while slower spinning leads to weaker but stretchier fibres.
The maximum strength of the silkworm silk can nearly be made to equal that of spider silk. [David Harris: Science news]
10:47:33 PM
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Today is ...
1918: Birth of Frederick Sanger, biochemist and twice recipient of the Nobel Prize in Chemistry
1902: Birth of Felix Wankel, inventor of the first rotary internal combustion engine
1819: Birth of Sir George Gabriel Stokes, fluid dynamicist
1814: Birth of Anders Jonas Ångström, a founder of spectroscopy
1642: Christiaan Huygens discovered the Martian south polar cap [David Harris: Science news]
10:44:10 PM
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Source of universe's gamma rays found
"Scientists at Columbia University and Barnard College have found that the majority of the gamma rays outside of our galaxy are likely emitted by galaxy clusters and other massive structures. This may resolve a 30-year-old mystery as to the origin of the Universe's gamma-ray background."
Details and animations [David Harris: Science news]
10:42:26 PM
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"I am a great believer in luck, and I find the harder I work the more I have of it." --Thomas Jefferson [Rick@Leaders.net: Quotes]
10:31:56 PM
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Wednesday, 14 August 2002
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Today is ...
1887: Birth of Erwin Schrödinger, one of the founders of quantum mechanics
1981: IBM introduced the personal computer
1883: Extinction of the quagga [David Harris: Science news]
12:37:25 AM
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What makes adolescents smoke?
A study of over 20,000 adolescents looked for familial, interpersonal and peer influences that might encourage smoking.
Peer smoking was the strongest predictor of increasing smoking by an individual. Parental smoking increased the chances of an adolescent smoking by 26%. However, mothers who smoke do not seem to create sons who smoke.
Smoking was increased by a factor of 9 for those who drink alcohol over those who don't.
Read the full paper [David Harris: Science news]
12:34:32 AM
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A touch more aout the child athlete.
Oh dear.
It's hard.
I will expand.
I'm fairly expanded now but you know what I mean.
12:27:26 AM
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World's smallest light-bulb
Researchers at the Georgia Institute of Technology have created light bulbs from groups of 2-8 silver atoms. Just pass an electric current through the clusters of atoms and they glow...
This is the first time researchers have seen electroluminescence from individual molecules.
More information and pictures [David Harris: Science news]
12:24:24 AM
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New Get Your War On is out!. ![[GYWO panel]](http://radio.weblogs.com/0110738/images/2002/08/12/war.078.3.gif "So true, so true") There's a new installment of Get Your War On out. Not as funny as prior strips, but it's still got it. Think of it as a comic form of this strip. I damned near projected my dinner through my nose when I looked more closely at the latest offerings. The included panel sits nicely right on its own. Fresh new insight from the Get Your War On guy. I had never thought of it that way.
That image is screwing up the layout on my weblog page. Must add more text to improve the flow. This is so lame. [ian in toronto]
12:08:32 AM
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Tuesday, 13 August 2002
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Another day.
I should talk sometime about having a child who is a potentially elite athlete.
One who is in an extremely expensive sport.
Can you imagine personally paying for a Formula 1 driver?
11:58:40 PM
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Monday, 12 August 2002
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The multimedia course information night went reasonably well.
Of course everyone there has their own agenda and their own slant.
They often act as though people (me) want to exclude them from learning.
Nothing could be further from the truth!
10:22:57 PM
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I have an information evening tonight for the multimedia course I coordinate. I'd love to put in links and stuff but I haven't quite got that together yet.
1:33:30 AM
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Today is ...
1837: Birth of Sadi Carnot, engineer who developed some of the foundational principles in thermodynamics.
1909: The ship "Arapahoe" was the first to use the international distress signal S.O.S.
1877: Asaph Hall discovered the two moons of Mars, calledd Phobos and Deimos [ | | |
