Asteroids likely source of Earth’s water

Bad Science examples from the media: Indian Express, April 29, 2010

Ice asteroids likely source of Earth’s water: Study

Astronomers have for the first time detected ice and organic compounds on an asteroid, a pair of landmark studies.

The discovery bolsters the theory that comets and asteroids crashing into Earth nearly four billion years ago seeded the planet with water and carbon-based molecules, both essential ingredients for life.

Working separately, two teams of scientists using NASA’s Infrared Telescope Facility in Hawaii found that the 24 Themis, which orbits the Sun between Mars and Jupiter, is literally covered in a thin coating of frost.

It had long been suspected that the massive space rocks that bombarded our planet after the formation of the solar system contained frozen water, but the two studies, published in Nature, provide the first hard evidence.

Still, a mystery remained: How could frozen water persist over billions of years on an asteroid hot enough to vapourise surface ice?

Only if that layer of frost were continually replenished by the slow release of water vapour released from ice in the asteroid’s interior, the researchers reasoned.

In other words, 24 Themis some 200 kilometres (125 miles) in diameter almost certainly contains far more water locked in its minerals than anyone suspected.

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This article has many flaws. At the very outset, the headline itself is misleading. Unfortunately the piece has fallen to the common temptation of sensationalising the news with an unholy bargain of the truth. Unlike what the headline implies, the asteroid Themis 24 is very much a solid mass covered with a thin layer of ice and not wholly made out of ice. If you want a sensational title, isn’t it good enough to just say “Asteroids likely source of water on Earth”?

Secondly, the article has been sadly stripped of so many important data points that it fails to make the point. For example, when asking the question “How could frozen water persist over billions of years on an asteroid hot enough to vapourise surface ice?” the writer gives no background to the reader about why is it hot enough to vaporise the surface ice. If the piece of rock is in between Mars and Jupiter then a common man would assume that the surface temperature compared to the Earth (which is much closer to the sun) would be lower. Thus, if Earth can have surface ice, then why can’t an asteroid? Although this logic is flawed in itself, it raises many more questions in a reader’s mind such as, is it because the asteroid has no atmosphere? or is it because it travels at a greater speed than earth? and so on. Also, the mystery question is wrongly posed as it should be ‘millions’ (what authors claim by their modelling) instead of ‘billions‘.

Thirdly, there is no mention of the timeline in any of the Nature articles and points to the classic error of ‘making up information’ for the sake of it. I suppose that the writer has come to a conclusion (if at all he has given this article any thought) that first sign of life was seen 3.5 billion years ago thus obviously, water would have come to Earth sometime before that. Thus, the use of “nearly four billion years ago.”

Fourthly, “Only if that layer of frost were continually replenished by the slow release of water vapour released from ice in the asteroid’s interior, the researchers reasoned.” This sentence will only confuse the readers ever more. Why does the ice in the interior of the asteroid sublime only to deposit back as frost on the surface? The more probable reason, as mentioned by the researchers, is ‘impact gardening’ which is the phenomenon of small bodies hitting the surface of the asteroid and churning up the subsurface ice. The impact might also be able to trigger the sublimation of subsurface ice, the authors believe. There is no mention of that in this article!

Finally, “24 Themis — some 200 kilometres (125 miles) in diameter — almost certainly contains far more water locked in its minerals than anyone suspected” is absolutely wrong. Humberto et. al clearly mention that “Although many asteroids show absorptions in this region, they are well matched by hydrated minerals. The spectral features of 24 Themis are significantly different from those in other asteroids and we show that it is accurately matched by small ice particles.” The point the authors make is exactly opposite. There isn’t hydrated minerals or ‘high concentration hydrated minerals’ that the authors observe but water in it’s free form as small ice particles.

As science writers we have the responsibility to communicate science correctly and such obvious mistakes will only create more doubts and lead the readers astray.

ResearchBlogging.org Rivkin, A., & Emery, J. (2010) Detection of ice and organics on an asteroidal surface. Nature, 464(7293), 1322-1323. DOI: 10.1038/nature09028 & Campins, H., Hargrove, K., Pinilla-Alonso, N., Howell, E., Kelley, M., Licandro, J., Mothé-Diniz, T., Fernández, Y., & Ziffer, J. (2010) Water ice and organics on the surface of the asteroid 24 Themis. Nature, 464(7293), 1320-1321. DOI: 10.1038/nature09029

How a Homeopath tried to understand the science behind Homeopathy

At Café Scientifique, last night, I heard Dr. Stephen Cartwright speak on ‘Homeopathy – Dispelling myths and establishing facts’. I had never been to one of these CafeSci evenings, but going from the description, I was hoping there will be many who will be interested in hard scientific facts and theories. Even then, I took a print of the Sense about Homeopathy poster published by Sense about Science, just in case anyone might be interested in knowing more about it later. But within the first few minutes of the talk, I knew I would not need it.

Dr. Stephen Cartwright, is a molecular biologist who, with support from private donations, started researching homeopathy in 2009. Prior to that he trained and setup his own business as a homeopath in Oxford in 1988. Last night, he began his talk with a story about how he first got into homeopathy, and that is when I neatly folded my Sense about Homeopathy poster and put it in my bag.

In 1984, he visited a homeopath, out of curiosity. After talking to the homeopath, he was prescribed some pills which he happily took; only to develop symptoms of sinus within 24 hours. That intrigued him and he took up the study of homeopathy.

‘After 20 years of practising homeopathy, I really wanted to understand the chemistry behind these remedies and that’s why I have put a lot of thought and came up with some experiments to gain some insight. He continued, ‘I will have to delve into some chemistry, please forgive the jargon.’ He goes onto explain his experiments. ‘It is well known’, he says, ‘that homeopathic potencies are affected by sunlight and magnets’ and thus of all the analytical techniques that man has invented to understand the chemistry of atoms he could only use was visible light spectroscopy.

Some definitions before we proceed; succussion means vigorous shaking of a diluted homeopathic preparation in order to activate the medicinal substance; potency is the dilution factor and in homeopathy, a solution that is more dilute has a higher potency.

Panacea? (Image: The Guardian)

Process: In a special cuvette, he mixes a drop of his potencies with 90% ethanol and measures absorption against a control. Control that he uses is non-succussed water, because homeopaths accept that water that has not been methodically shaken does not have any homeopathic remedy in it. The potencies which could be of various dilutions contain a poly substituted phenol. ‘More details cannot be divulged as it is a patentable finding’, he says.

Observations: With an increase in potency (increase in dilution) he sees increase in the absorbance. Different remedies give different absolute absorbance but same trend. The trend is not linear and because he hasn’t done enough experiments he is unable to calculate the trend. Also, a similar trend is observed with an increase in the succussion of a particular potency used. ‘Quite strange’, he admits.

Additional experiments: ‘Why’, he thought, ‘is it that all homeopathic remedies are made in ethanol?’ He did the same tests with 30 different alcohols instead of the potency and found that the trend was found to be exactly same in case 2,4-pentane diol. What does that mean? Now he goes a step further on his claims and makes another theory to explain this phenomenon, ‘2,4 pentane diol is like two ethanol molecules back to back, thus the potencies might be in some way ordering the ethanol molecules to arrange themselves to form something like 2,4-pentane diol.’

Wow! A Nobel Prize deserving discovery, why hasn’t he published it? Oh wait, there is a problem.

Problem: Results are not reproducible because too many factors affect his experiments, factors like time of the day, place in the lab, how many times was the potency shaken, etc. He also observed that when very rarely he has managed to have all the factors in control, he found that on somedays he got the result and on somedays he did not. So how to explain another strange pheonomenon? Of course, another theory. He hypothesises that there is an oscillation in the potency. On somedays it shows effects and on somedays it does not.

On clinical trials he says, ‘These oscillations are the reason why clinical trials fail. Homeopathic remedies behave in strange ways and these clinical trials don’t take that into consideration. Obviously, the results will never be as predicted.’

On expiry date he says, ‘Homeopathic remedies have no expiry date. On occasions, I have found 20 year old medicines are as active as one’s made today.’

Alternative medicine (Image: Chicagoland Homeopathy)

On future scope he says, ‘Homeopathy has been here for over 200 years. 40% of all prescriptions in India are homeopathic prescriptions. There is huge market for homeopathy but because it behaves in these strange ways we need new assays to test these remedies. The demand for these assays is urgent and the inventor will make a lot of money.’

At the end he quotes Sir Arthur Conan Doyle, who he claims based the character of Sherlock Holmes on a homeopath, “Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.”

Enough of the talk, let’s move on to question answers. I’ll enlist the ones I remember.

Q: When you went to the homeopath in 1984, what problem did you have?

A: Nothing, I was quite healthy. Huh? Then why were you prescribed pills? Oh that! You see in talking to him for over an hour, I realised there were so many things that were wrong with me.

Q: What are your thoughts about the claim that water has memory?

A: Perhaps, I don’t know, there has to be some way to explain this strange phenomenon. May be it is true.

Q: Were the oscillations random or regular like a sinusoidal wave?

A: As far as I know, they were regular. Doesn’t that mean that you can then time clinical trials on the days you know the remedy will have a cure!!

Q: Considering that the potency is shaken in 90% ethanol and your claim that with more shaking you observe more absorbance. Is it possible that ethanol is simply dissolving glass or some impurities that are present in glass?

A: I am not aware of it. We take care that the glass used is clean. Of course you do. Did we doubt that? We were talking about dissolving glass or the impurities that get embedded in glass during the manufacturing process.

Q: If homeopathy is so widely used, why hasn’t homeopathy come up with new potencies?

A: Of course we have, you will be able to find potencies of tetracyclines. But te

tracyclines are compounds made to combat disease. Making potencies that way is against the homeopathic principles, right? Homeopaths make potencies of things that cause the disease, right? Oh yes, we make potencies of tetracyclines to combat the side-effects produce by this drug.

Q: This room has many chemists today, including myself and we would to know if you would be willing to share your spectral data with us to let us analyse them?

A: Yes, I’d be willing to that. I am happy to collaborate. Surely, it will be better if you do this before you face the peer-review process.

Q: You have said that you have not published any of this research. But clearly these results have use for homeopaths, have you shared the information with them yet?

A: Not yet. I believe in coming up with a working hypothesis before I do that.

Q: Have you presented your results at a conference?

A: No I do not have money to do that. It is very difficult to find funding because of the fickle nature of the results I’ve obtained. But I will some day. That’s why I give talks at places like these. I came here hoping to be asked intelligent questions, of which there were none, so that I am able to hone my skills of defending my case of homeopathy.

It surprised me that in the many questions asked, no one ever brought the placebo effect into the conversation. It may be because even without that weapon he wasn’t able to come up with convincing answers for the audience. The last question he was asked is the best conclusion I could have asked for to conclude my blog post.

Q for the audience: Will people who have changed their minds about homeopathy after today’s talk, for the better or worse, please raise their hands?

3 out of about 30 raise their hands. The old man who asked this question says, ‘There, Dr. Cartwright, that was a predictable and I dare say, reproducible result.’