Tuesday, May 23, 2006

100$ Laptops on flickr

I had blogged about the MIT initiative a few months back. The pictures of the laptop can now be seen on flickr (thanks to Pete!).

The nature of the laptop to be expected (from the Project Website)
The proposed $100 machine will be a Linux-based, with a dual-mode display—both a full-color, transmissive DVD mode, and a second display option that is black and white reflective and sunlight-readable at 3× the resolution. The laptop will have a 500MHz processor and 128MB of DRAM, with 500MB of Flash memory; it will not have a hard disk, but it will have four USB ports. The laptops will have wireless broadband that, among other things, allows them to work as a mesh network; each laptop will be able to talk to its nearest neighbors, creating an ad hoc, local area network. The laptops will use innovative power (including wind-up) and will be able to do most everything except store huge amounts of data.

Saturday, May 06, 2006

Quails, the American Passion

I have nothing particular in mind writing this except for a strange coincidence of listening to Tom Wolfe reading about his book 'A Man in Full' and the Dick Cheney's quail shooting incident.

http://www.nytimes.com/books/98/11/08/ra/wolfe.ram The reading session was in the November of 1998.

In the audio file, if you listen to the first 5 minutes, Tom remarks...

He starts talking about private jets and then starts to say: "There seems to be the new Expensive American Passion. In Georgia 10 thousand, 20 thousand sometimes 50 thousand acres of land dedicated to shooting quails. ... You can have only two shooters at a time, as the birds don't fly over, but burst out of the tall grass in every possible direction. If you had 3 or more, you could have hunters shooting each other than the quails..."

Have fun!

Saturday, April 08, 2006

ABC : Peek at India

Videos from an ABC correspondent's recent trip to India: video 1 video 2

Video 1 is particularly interesting.

Wednesday, April 05, 2006

Richard Engel: War time coverage

Engel has an eye-opening perspective on wartime reporting. It is not that there are not many stories to be told, but how it can be told without blowing oneself up. He did emphasise that mostly Iraqi's believe the security situation is worse that what is depicted on TV.

the link also carries a video link to Engel's piece. Very interesting to watch and learn. This might even be a problem in (war)science. Can it enable the journalists in any way?

Tuesday, April 04, 2006

Narmada Dam(ned)

Medha with two other volunteers is on the seventh day of her indefinite fast.
Ms Patkar continues her struggle against the plans of raising the height of the Sardar Sarovar Dam and refused to break her fast even as Union Water Resources Minister Saifuddin Soz met her on the seventh day of the agitation today.
says the Chandigarh Tribune.

and this: PM Manmohan Singh is learnt to be keen that the issue be resolved says a TOI article.yes, learnt to be keen! now, you can go sleep in peace.

The raising of the height goes against the supreme court ruling claims NB!B!A (Narmada Bachao! Bachao! Andolan). Perhaps, soon somebody will be needed to save the Andolan itself. The issue of rehabilation has not been settled. The struggle has been on for 6 years! Sometimes you wonder how much struggle will break the indifference of these government that come one after another.

This is representative dmeocracy?

Friday, March 31, 2006

Rural Computing

The fantastic information revolution is reaching rural india. Intel is taking the lead.

I was wondering, all these years, if any of the giant sloths like Infosys, etc will look "Inside" instead of "outside". Now you really have "Intel inside". They may start to teach the giant sloths a new way of making business work and still serve communities.

The computers may not be cheap, but they are considering a pay-per-use model.

Wednesday, March 29, 2006

A Little plant that won't die

A coffee plant that does not die on NPR news.

don't banana plantains do the same? don't they self-propogate?

Tuesday, March 28, 2006

Evolution and Religion

Greg Graffin's Ph.D. work suggests that
  • only 10% of the people think religion is incompatible with evolutionary biology.
  • Relgion is an adaptation. A part of Evolution. That religion was manufactured by humankind.
  • Naturalist worldview proposed by evolutionary biology is harmonious with religion on one condition: If the tenets of theology such as 'existence of soul' or 'consciousness' and such are rejected as unnecessary.
A longer write up is available here.

Graffin is a evolutionary Zoologist who received his PhD from Cornell in 1991.

Monday, March 27, 2006

Global warming?

Here is a small ad. nicely done.


some say the irreversible consequences are 30 years away.

30 years?

that won't affect me.

Saturday, March 25, 2006

Warming up of Lake Tanganyika

An article on effects of a warming planet on its various communities has recently appeared on Salon.com. This is part of a series of reports on the effect of global warming on the various communities, jointly produced by NPR's 'Living on Earth', U.C. Berekely graduate School of Journalism and Salon.com
KALALANGABO, Tanzania: Tanganyika is the longest freshwater lake in the world, the second deepest and the second most biologically diverse. It is also getting warmer.

Along the shores of Lake Tanganyika, there are two kinds of fishermen: the ones who fish for an abundant nocturnal sardine called dagaa and the ones who don't. ... For generations, the dagaa were so plentiful, it never occurred to anyone the abundance wouldn't last. ... But now, Seph said, the catch is down. All along the Tanganyika basin, from Bujumbura in Burundi to Kalemie in the Congo to Mpulungu in Zambia, fishermen like Seph are beginning to say their lake is changing and with it, their way of life.
Whenever any discussion of global warming is brought up, the picture soon gets cluttered with indications to apocalyptic melting of arctic glaciers and flooding of mainlands in the future. People are now reminded that there could a slower and continuous destruction that is happening right now, as we speak, elsewhere farther from the artics, where communities have lived and thrived. It is time we took note.

Friday, March 24, 2006


Signs and Science

It was believed for a long time that Eggs can be made to stand on its end only during equinoxes. A superstitious belief rooted in the scientific fact that earths pole is tilted just the right amount so the day and nights are equal in length. Science has destroyed that belief and down goes one fond tradition of people in China; placing eggs on its end during equinoxes.

One Wayne Osborn, in Central Michigan University, has a tabulation of eggs standing on its end. The experiments ran for 3 whole months including the autumnal equinox on the 22nd of September.

All this because one equinox just passed us on March 22. This is supposed to be the official start of Spring! As Jon said: It bitter cold out here. If you see a ground hog, make sure to punch him in the face.

Friday, March 10, 2006

Delphi unveiled?

A NY Times article discusses the long time relation between religion and science: One more example, down this way, has been the revelations of Delphi Oracle and the stories related to it. A part of it has now been uncovered.
The recent discoveries of a renegade four-member team of scientists illustrate ... the truth behind the Oracle of Delphi's legendary powers, showing how the most influential figure of ancient Greece prepared for ecstatic union with Apollo. The scientists, ... discovered tons of bituminous limestone down below, its layers rich in intoxicating gases.

They also found two faults that crisscross beneath the shrine to form a geologic pathway to the surface. They even measured traces of intoxicants still bubbling up today. This and other evidence suggest that the Oracle inhaled a mist of potent gases that could promote trancelike states and aloof euphoria, helping send her into mystic ecstasies.
However, the euphoria did not extend all the way to other mysticisms.
They claimed no insights into how her utterances stood for ages as monuments of wisdom. They had no explanation for how the priestess inspired Socrates, or the seeming reliability of her visionary pronouncements.

If Science would encroach into realm of mystics, demystifying the myths, then mystic maybe forced to work harder creating new ones. Will Mystics catch up? How much does faith really depend on belief in Mysticism or Miracles?

Wednesday, March 08, 2006

As light leads us from Earth to the Sun

We may know our Sun (Our sun?) as it goes to sleep,
The sun went to sleep,
in a brilliant night dress,
That seemed to shorten,
as its light was seen less.
Until it had rested,
its weary warm head,
Within the cool blankets,
of moon glow, its bed!
-Linda A. Copp
or even as it is waking up
The sun in the morning.
Like a protective mother she rises and brings warmth to everything she touches.
Artists try to harness her beauty, scientists study to find her secrets.
Every being feels more alive when she is there sad when she is shrouded by a cloud.
She leaves each day with a promise to return that is never broken.
--By Bruce Patterson
But how well do we know our Sun? (this is probably the same problem every parent has with their child.) But keeping our discussion to the Sun; It is so scorching hot that we can't go near it, or peek into it to see what it is made of. This is not quite the truth.

Even as people reveal their true feelings when they become angry, any physical element shows its nature when it is very hot. The physics of it is: a hot body "feels" hot to us, and this heat comes to us as heat waves.

The light we see are waves of a particular length (or wavelength), and within them we see variations from blue (40 microns) to green to red (70 microns). One time when Newton passed white light through an optical prism, he found an image of a rainbow on the white screen nearby. This rainbow is the called "spectrum" of white light. You can also call it the signature of white light. Similarly when physical elements are heated at high temperatures, they begin to glow and emit waves, just like light, and that defines its own charateristic signature spectra. In the turn of the 19th century, enough progress had been made studying the signatures of Hydrogen and Helium at very high temperatures. (1000000 microns = 1 meter)

It was then possible to obtain signature of the heat waves coming from the sun and they began to show patterns that matched those of Hydrogen at high temperatures. This not only gave an idea of how hot the sun is (Its very hot!), but gave us an insight what is happening inside of it. The temperature on the sun is about 15 million degrees Celsius at its core.

At this temperature, as makers of the atom bomb also figured, many Hydrogen atoms can fuse into larger elements, thus producing a lot of energy. You see, the total mass of Hydrogen atoms is more than the mass of larger element produced. The remainder is released as energy in accordance with Einstein's relation that energy and mass are equivalent. We knew there was Hydrogen there and it was there at high temperatures. The patterns that matched were not exact, and what didn't match must have come from the heavier elements. You can also guess now that Sun has more hydrogen than of the heavier elements, as Hydrogen leaves heavier imprint on the signature of sun's heat waves than other elements.

So the theory was that Hydrogen fused to form Helium, and some Helium atoms further fused to form Carbon and so on. This theory is now backed by the signature patterns. We begin to appreciate how we have gone from visible light to make inference about the sun, which we can hardly look at. But, Sun is the Star of our solar system. Sun looks bright to us because it is so close to us. So the same story holds for all the stars that light up the night sky.

There are many unresolved questions. Will Hydrogen get exhausted? Remember some energy also comes from fusion of Helium atoms. How long will the sun last? How did it come to be in the first place. How old is it? There are many theories and each one was arrived at in its own peculiar way.

The sun went to sleep,
Within the cool blankets,
of moon glow, its bed!

Another day, Another time, Same blog.

Being on Cloud Nine »

Tuesday, March 07, 2006

Harassment : Blog-a-thon

What do you do if you are not someone who has been harassed, or have not seen anyone be harassed? That is more a question to me than to you. I guess there might be something right there.

Most of these incidents that I have read have been harassment where the victim's response is muted and does not draw attention to the harassment when it happens. Perhaps, in a society where people take their perceived self-respect a little seriously, they continue to engage in this behavior not because they won't get referred to the police, but they won't even evoke a whisper. At least in all cases where the victim knows what is happening to them, and can raise the issue. I think that might have made the issue claimed to be present everywhere to be there on every mind too. Won't you think that would help?

Monday, March 06, 2006

Sunday, March 05, 2006

Science Update : India

Recent Developments

A group of Indian researchers, Pankaj Joshi of TIFR, his student Rituparna Goswami, and Parampreet Singh of Pennsylvania State University, have found and proposed an experimental test for the quantum theory of gravity. "Validating quantum gravity is a necessary step in having a unified theory of forces of nature" says Dr. Joshi. We may also remember the "Primes is in P" paper by Manindra Agrawal, Neeraj Kayal, and Nitin Saxena of IIT-Kanpur. Or, even the work of Abhas Mitra of BARC.

Science and Society:
  • Scientists have isolated anti-malarial compounds from Mussels, and these can be prepared without killing the Mussel. The discovery came from a team led by Dr Anil Chatterji of NIO. Shreya Life Sciences, a Mumbai based company has the right to commercial production of the compounds.
  • Even as progress is made in medicine, you would think a patient can't be blamed for not responding to treatment!

  • The Indian Budget for the Fiscal year 2006 has allocated 16% of GDP for endeavors in Science and Technology. As part of this, chosen universities will receive large research award to develop and nourish scientific programs.
  • President Kalam has exhorted the scientific community to engage in finding and developing alternative sources of energy on the National Science day. He envisions an energy independent India by 2030.
  • Hyderabad has now become the Genome Valley of India, one of the largest such bio-technology facility in the world. The facility will house among other things an international life sciences institute, a world-class animal resource facility and a biotech incubation centre for start-ups.

Friday, March 03, 2006

Journal access to Africa

The Royal Society of Chemistry (RSC) has announced that it will give Africa free access to its journal archives. A total of 1.5 million pages and 250,000 articles will be available electronically to African scientists.

Science Key to Africa's Future: To drive home the point, Professor Calestous Juma, co-ordinator of the UN's Millennium Project Task Force on Science, Technology and Innovation says "If all the aid from Live Aid was spent on agricultural colleges rather than relief, Ethiopia would not be in difficulties today".

Open Access Movement has been around for years fighting the idea of mandatory paid subscriptions to access journal articles as it impedes the academic dissemination of ideas freely among the scientific community through out the world.

some outlets for free public access to journals are PLOS, arXiv, and there are many more.

Thursday, March 02, 2006

Lyrical Limerical

friends gods send

walk with your hand in mine
this way brotherhood will gain
in a future so bright
country can take pride
this journey will not be in vain

air eclair

i don't remember jack abramoff
hey journalist, you back off!
I tell you, in honest!
once there 'was' a forest!
no clean air, childrens cough

havana marijuana

marijuana keeps your pain at bay
medical of course, didn't I say?
no side effects, no no
not until well, you know
an elegy comes to me from far away

kicks of limericks

hey you, this is all just limericks
write some and get some kicks
out of it. you care?
have time to spare?
write yours on glossy lipsticks

Harassment. Will it stop with us?

Annie's post, Streets, stories, strategies, for a woman on the streets of bombay: filled with anecdotes, tips for survival, what to expect, things that will make you cringe. Another post that is worth reading more than once. A post that appeared much earlier on the same issue : On being a female body by Charukesi. Reading all this also reminded me of an op-ed: Rape is Murder by Vir Sanghvi on the Delhi rape incidents.

On a follow up note, there is a Blog-a-thon on the issue of street harassment, you can blog your thoughts, experiences, and comments on March 7th. You can have your intention to blog announced early by emailing to blurtblanknoise [AT] gmail.com before the coming Monday (6th March).

Wednesday, March 01, 2006

Scian Melt 14

Science and Society

Sunil has his blog on Medical developments including Avian flu in China and how it is being managed. Sowmya has an elaborate blog on the role of Radon in your lives and on Dishwashers and Suds, a blog exemplifying 'scientific curiosity as part of our lifestyle'. I have been making some attempts to find out the 'how of supercooling' by looking at two of its examples: Hand Warmers and Clouds.

Sujatha has written a vey nice blog on Caserean Sections in India: analyzing from both the mother's perspective as well as from the doctor's perspective. Gurcharan Das argues for how burgeoning prospects for education in India can help position it as a powerful knowledge economy. On a related note, Sujatha narrates the story of Noor: a foot-soldier on war against illiteracy.

from small to big:

Aswin gives us the deal with the Big Bang theory. On the smaller end, Selva has blogged on Quantum Computing and Cryptography and how you can hide your secrets.


Abhinandan carries a discussion on the recent denial of visa to Indian scientists by US immigration authorities, its consequences, and the barriers to science caused. At the same time, India isn't doing too badly for herself. Amardeep blogs on India's new digital library project in progress, much like Gutenberg. Even as we progress in our sciences, our failings in leaving Indian women in tatters is a cause of woe and concern: from Uma of the other india blog and Peppy of the perpetualmisfit blog. This is not all, as Dilip blogs on two cases of rape and homicide that have come before the justice system only to slip away without notice. But then Dr. Indumathi bridges both issues: A scientist with a social conscience (link courtesy: Selva). Talking of integrity, Prashant blogs on Why are Indian politicians this corrupt? claiming they aren't quite as corrupt as they are just effectively playing a game of survival in a system whose rules are larger than themselves.

Link to Previous Scian Melts can be found on the announcement blog. For future nominations write to melt [at] thescian [dot] com

Charon's Cousins

Observations with the Hubble Space Telescope from May of last year show two tiny dots revolving around the same center of gravity as the ninth planet (Pluto) and its largest moon, Charon.
(yes, even the moons have a name!)
"We used Hubble's exceptional resolution to peer close to Pluto and pick out two small moons that had eluded detection for more than 75 years," says Hal Weaver, an astrophysicist at Johns Hopkins University and the discovery team leader.
Based on their brightness--and assuming that their surfaces are about as reflective as Charon's--the scientists believe the two moons are roughly 38 miles and 29 miles in diameter.
Given that they share Pluto's distance from the sun--roughly three billion miles--but are 4,000 times fainter, it is not surprising that the satellites eluded detection until now, the researchers say.
--Thats how large the distances are. If you were looking at your palm, and see the wedges between the palm lines, imagine a palm sitting there with its own palm lines, and do this a 1000 times, thats how small the moons appear when we place the distance between the Sun and Pluto into perspective. Hubble telescope is quite a remakable window to outside of our world.

--How do I know what a solar system is? Is "my world" all that I can see? What if the tenth planet has already given its loyalty to another Sun or a Star?

--From the Scientific American article

Friday, February 24, 2006

Scian Melt Nominations

The next Melt will be hosted on this blogspot page on March 1st. You can find more about The Melt here. If you have written a blog page on Science and/or India, you can make your nominations to melt [at] thescian [dot] com. The previous one, the 13th one, is hosted here.

The following places also carry further announcements and information: at shallow thgts and at Scian


12:NeoSagredo, 11:Shallowthgts, 10:Kyun, 9:Reflections, 8 and 7:Scian, 6:Geomblog, 5:Patrix, 4:Tiffinbox, 3:Sel.Amnesia, 2:Rathod, 1:Scian

Tuesday, February 21, 2006

Being Human and Science : Linkspress

Being Human can be tough. Especially in medieval times. Because of this, we came out for the better and turned out to be most social of animals, anthropologists say.

Now it is time for us to get back at them; the species in our neighborhood. Humans perceive animals, insects as sources of threats or infections. It turns out, we have been making the wildlife sick!
"With emerging infectious diseases of wildlife today there's almost always some human component," say Dr. Lewis, an NSERC-funded mathematical ecologist in the mathematics and statistics department at the University of Alberta, Edmonton, Canada.

in a landmark paper, he helped document how commercial salmon farms off Canada's British Columbia coast are a breeding ground for sea lice, a parasite that then infects young wild Pacific salmon. The research was the first to document the parasitic impact of commercial salmon farms on wild salmon in the Pacific Northwest.

When it comes to emerging infectious diseases of wildlife, Dr. Lewis says that public perception and policy needs to move beyond seeing "special cases" to seeing the constant role that people play.
Unlike the research above popular science need not be of good quality as much as having a wring of currentness to it (the be hip mantra!). Perhaps the blame lies with the schools and the science teachers for not being able to convey the pleasure of science. Here is a nice article about that.

Added 2/22:
Ice Ice Baby If you thought you knew why ice is slippery, think again! Even the scientists are not sure what the reason is, says a nicely written NY Time piece.

Science off the tap! To bring the science fervour to the public, Cafe Scientifique started in Leeds and slowly spread to other places including its now popular home in Denver, CO. People gather to disucss about all science topics that affect their life from genetics to cancer research.

Monday, February 20, 2006


Just to have fun with orientation, try making a Moebius strip. If you have a normal rectangular strip of paper, you can join one short end to the other to make a simple closed strip. IF you twist one end (by 180 degrees) first before joining with the other end, you have a Moebius Strip. The ants in the picture are actually on the same side of the strip, even though they appear to be on two sides. An ordinary strip has two sides (an inside and an outside), but a Moebius strip has only one side!

Think about that! :)

Take the normal rectangular strip and join the long ends to make a long cylinder. Just as in the case of the rectangular strip above, close the circles in the two ends of the cylinder in a simple way to make a hollow doughnut (a torus). What is the analogue of the Moebius Strip for the long cylinder? It is a Klein Bottle! A hollow doughnut has an inside and an outside, but a Klein Bottle does not. So it cannot hold any water as inside is also outside :P

Caveat: Klein Bottle does not physically exist in 3-dimensions (but in 4 dimensions!), so the picture is an illusion. I don't want you to get all cross-eyed looking at it. :P

Friday, February 17, 2006

Being on Cloud Nine

What would it be like if you were in the middle of a cloud? Can you Imagine millions of droplets of water floating around you? These droplets are very small, and they float around you without touching each other. This is how it would be to be among the clouds.[1] So is it all just water? Why don't they fall down? We can wonder what goes on up among those clouds, sitting here on the ground beneath our feet. (read my earlier blog to know about supercooling and crystallization).

The water droplets are so small that they can be kept afloat by small wafts of upward wind, more like a feather in the air that will float and float and float but will never fall to the ground. The droplets are kept from running into each other by the same air, which acts more like a foam cushion that keeps a high-jumper from bumping into the floor. You can imagine these droplets danced around by the wafts and yet not bumping into each other.

There is something more to clouds. Clouds are also very cold. So cold that it can be below -40 deg C (now you are having second thoughts about being in the cloud). You must have read my earlier blog and wonder: how can water remain unfrozen? The answer also lies in the same blog. For water to freeze, it needs points of crystallization. Up in the clouds these are provided by suspended particles (dirt) in the air. But as you can imagine, a cloud living so high is also far from the dust and dirt of the Earth![2] So it is very hard to find such dirt that can make crystallization to happen. So water droplets remain water droplets but at temperatures much below zero.

So all these droplets go as clouds from one place to another, to another. When do they ever come down as rain? Will they fall on me? The first question is easier than the second. So, we will answer the first.

As we understand it, supercool water (water below zero deg C) becomes unstable as the temperature decreases. Only the slightest disturbance is needed for it to freeze. So lower the temperature the less impurities are actually needed to cause the disturbance. After all, even in the clouds there are impurities, though not as many as on the surface of the Earth.

We know that warm currents and cold currents all have a thing going of their own, independent of the clouds. Where they come from, how they come, we don't care. But if enough cold winds come to make the supercool water droplet's temperature drop below -40 deg C, then crystallization can start. So droplets turn to ice and slowly the surface of ice (flake rather) becomes the source of further disturbance and the crystallization spreads through the cloud. There is an additional effect that happens here. There are wafts of wind blowing between the droplets. This air is rich in moisture (it contains water vapors) and on meeting ice, the moisture in the air, condenses and then freezes to form more ice.

We remember well that the droplets are floating away from each other. So, as the ice starts to form, the cloud does not become a block of ice but a cloud of snow flakes, all ready to fall. As they fall, they melt and drop as rain droplets, only much bigger ones than the ones in cloud. How so? The air added more ice to them from the moisture it was carrying, remember?

Most of the drops evaporate as the fall down, due to the resistance from the air, just the same resistance we feel when riding a bike on the road. The clouds contained in a cube of one kilometer for each side, weight about a few hundred tonnes, so heavier the clouds the more drops that actually fall down on it, heavier the rain.

So that is the story of rain. You may prefer to stand in the rain than to be among the clouds.

We can tweak science to create rain in places that don't traditionally receive rainfall. If you remember the relation between supercool water and disturbance needed for crystallization, we needed a lot of cold drafts because there was not much "dirt" up above. Now this is the reason why clouds pass by without raining. So what scientists propose is to introduce "dirt".

What I cannot explain well is that one kind of "dirt", when introduced, can actually trigger crystallization at a higher temperature than some other "dirt". Silver Iodide can do this at -20 deg C where as usual crystallization needs well below -40 deg C. The process of introducing Silver Iodide in clouds to create the rain formation artificially is called seeding the clouds. Silver Iodide needs to be sprinkled fairly well inside the cloud, so crystallization will be uniform. Or rather, the upward drafts must help mix silver iodide fairly well in the clouds. There are hundreds of factors that need to go right so rain can be formed from the clouds. Here is two important ones

1. If the cloud isn't precisely downwind from the target area, the rain will fall in the wrong place anyway.
2. If the seeding is done at the wrong time, or on the wrong cloud, it may cause "cratering," or large holes in the cloud that cause it to fall apart. So an errant effort can destroy the clouds that might otherwise produce rain.

[1] Its not all water. There is some ice too. But not so many that can induce crystallization. But mostly water.
[2] The reason why dirt and dust are less at higher levels is rather simple. Anything to rise to that level against gravity must have really small weight, or can be vaporised in gas form. Most dirt don't become gas, and as the threshold of weight becomes smaller, fewer kinds of dirt can qualify.
[3]Stratus, Cirrus, Cumulus are three common varieties of cloud.

I spare you from reading this rather longish article, by quoting some interesting excerpts from it:

The researchers have found: Rainfall from seeded clouds lasted longer than rain from unseeded clouds, the rainfall covered a larger area, and total precipitation was higher, sometimes even doubled. And in many cases results began just 20 minutes after the seeding.

Mr. Bruinties is now in the United Arab Emirates conducting a three-month feasibility study to determine whether conditions there are right for a cloud seeding program. Remember, not all clouds can be seeded.

Only certain clouds, early in their formation, are useful, and timing is everything.

Other seeding agents have been researched for the last 40 years, along with the importance of other conditions that help seeding to arrive at a better understanding of the process.

This resource provided the most material for the above write up. The following is another excellent very understandable discussion on everything there is to know about clouds. Recent News on Cloud seeding in Wyoming (Jan '06), and other ones in Australia, South Africa, Texas, and Israel.

Trivia: The Arctic ground squirrel hibernates at a body temperature below freezing--and yet doesn't freeze. The ground squirrel is able to do this because before hibernation it goes through a sort of internal purification that gets rid of any particle that might seed the freezing process. Liquids require such a particle (sometimes called a nucleus) in order to freeze. By purging itself the squirrel avoids becoming an ice cube, even if the temperature drops below freezing. (Link to Source Courtesy: Pradzie)

« As Light Leads us from Earth to the Sun

Warm your hands with Supercool Liquids »

Mirror Mirror ...

I found this problem in No Ordinary Genius by Christopher Sykes. It's pretty easy.

You look in a mirror, and let's say you part your hair on the right side. You look in the mirror, and your image has its hair parted on the left side, so the image is left-to-right mixed up. But it's not top-to-bottom mixed up, because the top of the head of the image is there at the top, and the feet are down at the bottom. The question is: how does the mirror know to get the left and right mixed up, but not the up and down?

--Question Posted by Richard Feynman

Check out Disoriented? to become really disoriented.

Thursday, February 16, 2006

how small are atoms?

Why are atoms so small? To begin with, they are very small indeed. Every little piece of matter handled in everyday life contains an enormous number of them. Many examples have been devised to bring this fact home to an audience, none of them more impressive than the one used by Lord Kelvin: Suppose that you could mark the molecules in a glass of water; then pour the contents of the glass into the ocean and stir the latter thoroughly so as to distribute the marked molecules uniformly throughout the seven seas; if then you took a glass of water anywhere out of the ocean, you would find in it about a hundred of your marked molecules
--Erwin Schrodinger 'What is Life?'(1944)ISBN:0521427088

Of Many Worlds in this World

Just like as in a Nest of Boxes round,
Degrees of Sizes in each Box are found:
So, in this World, may many others be
Thinner and less, and less still by degree:
Although they are not subject to our sense,
A World may be no bigger than Two-pence.
NATURE is curious, and such Works may shape,
Which our dull senses easily escape:
For Creatures, small as Atoms, may be there,
If every one a Creature's Figure bear.
If Atoms Four, a World can make, then see
What several Worlds might in an Ear-ring be:
For, Millions of those Atoms may be in
The Head of one small, little, single Pin.
And if thus small, then Ladies may well wear
A World of Worlds, as Pendents in each Ear.

-Margaret Cavendish (1623-1673)

Saturday, February 11, 2006

Warm Your Hands with Supercool Liquid

Keywords: Supercooling, Hand warmers, Crystallization.

If you hold on to the thread till the end, you might actually learn something. As a teaser: The title is sorta accurate. Read on to find out.

My friend and I went that evening to the sports store to do some ski gear shopping. As we left the store for another to do some price comparison, we entered into a chat with the guy at the counter. He said he was going to buy ski mittens instead of ski gloves. Minnesota cold meant mittens, which offer additional warmth for fingers (as they are next to each other). Mittens are also convenient for using hand warmers in them (these are heating pads inserted in the back of the gloves for additional warmth).

Hand Warmers: So our discussion turned to reusable hand warmers (see picture. the metal is at the bottom of the pouch). He showed us a small plastic pouch of liquid with a penny sized metal plate inside it. When the metal is bent, the liquid slowly starts to turn solid and white, and releases a lot of heat while solidifying.

The liquid, it turns out, is sodium acetate, which is a very specially suited liquid for use in hand warmers. The process of releasing energy it turns out is due to two other very special processes called supercooling and crystallization. These can be observed by performing experiments which you can do yourself either by buying an handwarmer pouch or even with water (you have to work extra hard for this).

Cooling and Crystallization: Supercooling is the principle that lies at the bottom of this heat release. Cooling, as we know it, is a process by which temperature of a liquid (think water) is reduced. As the temperature goes down slowly the liquid starts to turn into solid. What is really happening here is that liquid starts to go through a change in phase (from liquid to solid) as the temperature goes down.

In fact you can see that until the temperature reaches zero, the water remains water. No ice. When temperature reaches zero, the process called crystallization starts (nobody really understands how this works). Around an impurity or a surface with irregularities (even smooth surfaces have a small amount of irregularities), the water molecules find the source for some kind of a disturbance to their liquid state. At these crystallization points, water begins to crystallize (that is, becomes ice), right when temperature hits zero. Slowly as crystallization spreads, the surface of the ice thus formed becomes a natural site for further crystallization of the uncrystallized water that remains. Water placed in an ice cube box becomes ice much faster than if kept in a vessel: because the amount of surface irregularities for potential crystallization is larger in the ice box. The temperature at which the liquid crystallizes to solid is called the freezing point temperature. So that is the short primer on cooling and formation of ice for you.

Supercooling: If you cool a liquid very quickly and much below the freezing point temperature, the liquid can avoid crystallization and remain liquid. But, now it remains liquid at a temperature lower than the freezing point temperature. For this process, it is important that as the liquid is cooled it remains still and undisturbed. Even slight disturbances can provide a site for crystallization to start.

Crystallization and Heat: So when this supercooled liquid is disturbed, it immediately begins to crystallize. But then, when it crystallizes its temperature is restored to freezing point temperature. So all this energy that comes from crystallization (called latent heat) is released outside. If you must know, this kind of reaction where energy is released outside is called exothermic (exo=out, therma=heat).

Back to Hand Warmers: So this is what is happening with sodium acetate. It is naturally in the liquid form above 54 degC. On cooling, it will freeze at 54 degC. When I found this liquid pouch of sodium acetate at room temperature (25-30 degC), it is liquid at a temperature clearly below its freezing point temperature. But this pack is shaken, transported in trucks and sold in shops. How is it possible? Well, it turns out sodium acetate is special. It is very stable as a supercooled liquid. It needs heat to be supplied to disturb its condition and induce crystallization.

This is precisely the point of the metal piece inside. When the metal piece is bent, it produces a very small amount of heat; Heat that is good enough to make sodium acetate crystallize. Then sodium acetate freezes and restores itself to 54 degC. We find that it is heating up our hand because our outside body temperature is 25-30 degC.

So this is the cool story of how supercooling, crystallization, and sodium acetate come together to make our hands warmer.

Actually there is more unexpected stuff. You will have to wait until next week to find out, and this time you don't get to choose the liquid, but the metal.

Additional Notes:
[1] I never told you why the hand warmers were reusable. So what needs to be done with frozen crystallized sodium acetate is a careful process of boiling and cooling back to room temperature (remember that this is below the freezing point temperature of sodium acetate). So place this pouch in hot water and make sure every crystal is melted to liquid. Then let it cool without any disturbance. Since sodium acetate is quite stable it will supercool to room temperature nicely. Then you can reuse it by bending the metal plate again. You can do this experiment with water. However, though cooling water below zero degC (say to -2 or -3 degC) is possible, you have be sure that the container remians undisturbed throughout the experiment. And remember, water is not as stable in the supercooled state as sodium acetate.

Some >links<
How hand warmers work (scroll down), wiki on hand warmers and an experiment (.pdf file) with handwarmers. How supercooling might be useful in metal treatment and hydrogen fuel cells Understanding exothermic and endothermic reactions from pbs A demonstration of supercooling in water

[1] During the Korean war (circa 1924), Japanese soldiers mixed warming powder (a mixture of iron, water, cellulose, vermiculite, activated carbon and salt) with water to generate heat to help keep soldiers warm in the bitter cold of the wartime battlefield.
[2] Rusting of Iron produces heat, but the process is so slow that you don't notice it.

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Tuesday, February 07, 2006

$100 Laptops and Newton's Dog

Massachusetts Institute of Technology has been working on a new kind a laptop: one that costs $100, works on opensource Operating System and software, run by a 500MHz processor and has a 1GB Flash RAM instead of a hard drive. It is said that the target price is likely to come down once the product goes into production. The laptops will not be available for the general public to purchase.

Kofi Annan, while unveiling the first prototype in the World Summit on the Information Society, said "It holds the promise of major advances in economic and social development. But perhaps most important is the true meaning of 'one laptop per child.'"

MIT Tech Talk covers the lap-top project (pdf file)

The project website

The World Summit Coverage on MIT press

This is old news, but something worth covering. Also in the same vein I would like you to check out: Newton and the Walking Dog by Balaji for more than one reason. It takes a non-text-bookish approach to understanding the Newton laws (what is there to know about it?). The presentation is aimed at secondary school children, but it has surprises irrespective of the "level" of the reader. It costs only Rs. 150. The author is one of the finest people I have met. He also leads the AID India team. I will post a review soon (watch this space!)