A sense of universal perspective

The Hubble Space Telescope (HST) has once again been peering into the dark depths of space and has delivered us another spectacular image of the farthest reaches of the observable universe¹. This image was taken using a recently installed wide field camera, which detects light in the near infra-red portion of the light spectrum, just beyond the red part of the spectrum and which is invisible to human eyes.

HST Ultra deep field image (click for larger view)

The space telescope stared intently at a tiny spot in the sky, which to the naked eye and even most telescopes would appear dark and empty. Over the course of 4 days of looking at that one spot, the individual photons of light exposed an image of hundreds of galaxies in the outermost regions of space.

If this image doesn’t blow you away, then perhaps you just need a little perspective. You might want to take a seat first. In Douglas Adams’ The Hitchhiker’s Guide to the Galaxy the process of achieving a sense of perspective in the universe was the most tortuous thing any sentient being could undergo and a machine was invented to do just that. It was called the Total Perspective Vortex and it gave its victims a true perspective of their place in the universe, which amounted to a “microscopic dot on a microscopic dot”.

I promise not to fry your brains, as the Total Perspective Vortex did, but will instead attempt to open your eyes to the awesome size of the universe. Let me start by describing what a galaxy is, by describing our own: the Milky Way. It is comprised of a few hundred billion stars, much like our own sun and a great many of which have planets orbiting them too. These are the stars we see when we go outside on a dark, cloudless night and look up at the sky.

To appreciate the size of the Milky Way galaxy, we measure it in terms of the time it would take a light beam to travel from one side to the other. In the vacuum of space, light travels at 300 000 km every second, yet it would still take 100 000 years to traverse the galaxy.

Now look again at that picture from Hubble. It contains hundreds of galaxies. And that is just a view of a tiny speck of sky. As far as we know, looking beyond the stars of our own galaxy, every other speck of sky would show the exact same thing: galaxies extending in all directions as far as we can see. And if we could look beyond all those galaxies in the picture, we would likely see more and more galaxies. Because the universe is expanding, the light from all the galaxies will never reach us, no matter how long we stare, but it is obvious that the little we can see is far from little.

If you still can’t wrap your head around what you’re seeing and want to try another perspective, watch the following video from the American Museum of Natural History. It starts with a view of planet Earth and proceeds to zoom out until the view encompasses all the known and observable universe. Hold on to your hats for a wild ride.

When it appears that those around you are busy staring at their proverbial navels, investing their time in the celebrity gossip pages or concerning themselves with how many angels could dance on the head of a pin, it is refreshing to stand back and appreciate the true magnificence of the wider universe in which we live. You may think the universe is something out there and far too distant and abstract to be regarded a part of our daily lives, but thanks to the incredible science and engineering that gave us tools like the HST, we are now able to visualise it, measure it and come to understand it. The universe is here and we are a part of it, and it is more incredible than anything our imaginations might conceive.

Notes and references:
1) Hubble’s Deepest View of Universe Unveils Never-Before-Seen Galaxies
2) Thanks to gfish for bringing this video to my attention.

Controversial: Science to be taught in schools

Teaching kids about the way the world works, insofar as it can be ascertained using the tools of science, is something we’ve come to expect. Should it therefore be a subject of controversy? The British House of Commons has recently passed legislation that will require primary schools to teach evolution to kids and I have no doubt it will ruffle a few feathers.

Science class ^†

Why this should be a big deal in the 21st century, is hard to comprehend. Do these same schools not teach their students that fire requires oxygen to burn, demonstrating that a flame in a sealed space will be extinguished when the element has been consumed, or teach them why a bulb lights up when a switch is closed and current flows through a circuit? These are all examples of classroom science and the teaching of evolution should be no more remarkable.

This legislation will almost certainly be met with misgivings and protest from some quarters, most notably from groups with faith-based agendas. Such groups are very powerful in the United States where such laws would be near impossible to enact in most states, and unfortunately their influence extends across the pond to the United Kingdom.

Concerns over teaching evolution in primary schools would probably not have been raised even one or two decades ago, other than that the subject is perhaps better left until the later school years, which is a valid argument. Some faith groups, however, would have you believe that the subject should not be taught because it is wrong, and their voices are getting louder as they gather more and more support for their anti-scientific ideas.

Dismissing the overwhelming evidence in support of evolution, built up in the 150 years since Darwin wrote On the Origin of Species, they would have you believe that the entire world was created by a supernatural being or some other intelligent designer. Many Biblical creationists would endorse the teaching of their belief that the Earth and everything upon it was magically brought into existence a mere 6000 years ago!

Excessive government control over what is taught in schools is neither practical nor desirable, but this new step is necessary for the sake of our children and the generations that follow them. By properly educating our children and giving them the tools to reason for themselves, we can thwart those who would have us living in the dark ages, ignorant of the truth of the world, slaves to religious doctrine.

† Image by bowbrick (Creative Commons attribution)

If science knew everything…

When responding to someone’s extraordinary claims with a little bit of critical thinking and perhaps some contradictory science, a common retort is that “science doesn’t know everything”. I believe this stems from a terrible misconception of science and perhaps a mistrust of the scientific establishment. If science did know everything, there would be one very large book called “Science” with all of the answers to all of our questions. As a more concise person than I put it “if science knew everything, it would stop” ¹. The reason we have scientists is that there are many many unanswered questions and even more cropping up all the time.

Quackery ²

Someone used this gambit against me the other day when I contradicted their belief in the efficacy of homeopathy by referring to the fact that properly conducted scientific trials have never been able to show that it works ^†. I had also pointed them to some useful resources where they could find the same lack of supporting evidence. But the tired old statement was dragged out once more, like some reluctant freak led out on a leash in a circus sideshow: “but science doesn’t know everything”.

Science has tested alternative medicines such as homeopathy, despite the fact there there are no apparent mechanisms by which they might possibly work, other than the placebo effect. The results: no therapeutic benefits compared with the placebos in test after test. The scientific method has failed to show that it works; it simply hasn’t been shown to heal people. This doesn’t mean that it cannot possibly work, just that we have no reliable evidence to support the claim that it does.

The fact that science does not prove that it cannot work is to some people a license to say, once again, that “science doesn’t know everything”, and to somehow use that as a justification for prescribing quack medicine to patients and telling them it will make them better. Perhaps these people think science should keep testing their “medicines” until it gives them the answer they want to hear. And for how long should they continue to test? A decade, a century, a millennium? Or should science pursue more reasonable avenues of research with medicines that do appear to work?

Science does not have all the answers and neither is it perfect. Advocates of complimentary and alternative medicine (CAM) often cite the fact that conventional medicine sometimes gets it wrong. I must agree. Despite rigorous testing, conventional medicines are rarely perfect, but we can at least have some faith in the system because it is self correcting. It continually tests and re-examines its drugs and therapies, sometimes reversing long established policies and procedures when mistakes or poor practice are revealed. You can not have the same faith in alternative medicines, which are all too often completely unregulated, especially those whose roots are a couple of hundred years old and whose fundamental principles have not changed in that time. With new evidence, science based medicine adapts, but when tests reveal no evidence for the efficacy of a drug or therapy, there is a point at which the most rational thing to do is to abandon them in favour of pursuing those that appear more worthwhile.

Just because scientific knowledge is incomplete and its medicines far from perfect, does not make it permissible for every form of quackery and nonsense to be put on an equal footing with science based medicine. When the alternatives are shown to work, they might then achieve equal status. Or to put it another way, alternative medicines will simply become known as medicines.

References and notes:
1) Homeopathy & Nutritionists vs Real Science!
2) Image by Maxey (Creative Commons attribution)

† Clinical trials should be double blinded, use control groups and involve a large enough data set to provide statistically significant results. The research should also be peer reviewed and the results reproducible before it has any credibility. Advocacy groups sponsoring such research often fail to conduct trials in the proper manner and will only publish a favourable result which supports their claims. Make sure they are using the scientific method correctly before drawing your own conclusions.

Lunar deep freeze holds water

Now that the dust has settled, both metaphorically and literally, the scientists at NASA have managed to take a careful look at the masses of data gathered by the LCROSS mission to the moon and are already reporting great success¹.

Lunar craters ²

The mission went according to plan, crashing a spent rocket booster into a crater of the moon on the 9th of October, while instruments aboard the shepherding spacecraft viewed the event and the resulting plume of ejected material.

This “bombing” of the moon, as some media sources liked to call it, was eagerly anticipated by the inhabitants of Earth, who were expecting to see something spectacular. Nothing about this kind of science is guaranteed and the enormous spray of gas, dust and debris did not materialise, much to the disappointment of those watching through telescopes, or at the live images broadcast on TV and over the Internet.

The reports that came out over the following hours and days sounded like a collective “blah” as the public turned its back on space science with a dismissive wave of the hand. Many journalists, talking heads and commentators, unimpressed with the lack of “fireworks”, questioned the value of such interplanetary ventures. Science doesn’t always give instant gratification and those criticisms were premature. After a careful examination of the data, some preliminary results are now in, and they are far more interesting than any puff of gas.

The cloud of debris kicked up by the rocket impact actually reached several kilometres above the lunar surface, exposing long frozen material from within the permanently shadowed depths of the target crater. Spectrometers aboard LCROSS recorded the presence of the constituent elements in the ejected material, as they were lit up by the sun for the first time in a few billion years. From these data, NASA scientists have already concluded that there were “significant” quantities of water ice present there.

The availability of water on the moon would be a big asset for future colonies there, providing not only drinking water but also oxygen to breathe and fuel to power the habitat. These lunar deep freezers may also contain other interesting elements which might hold clues to the formation of our solar system. Again, the scientific methods requires a little more patience from us, while the data from this valuable and intellectually profitable mission continue to be analysed.

References:
1) LCROSS Impact Data Indicates Water on Moon
2) Image courtesy of NASA (far side of the moon photographed from Apollo 11 in lunar orbit).

Interpreting the bogus

The legal battle between the British Chiropractic Association (BCA) and the science writer Simon Singh slogs on. The BCA brought the libel case against Singh for his article in the Guardian which referred to certain chiropractic treatments as bogus (see Science misjudged).

It looks like a David and Goliath fight between the freelance journalist seeking the truth and the menacing power of an entire organisation with a lot of self interests to protect. One wouldn’t have blamed Singh if he had bowed out of the fight as soon as his mighty opponent entered the ring; this legal farce has probably cost him dearly and it is still ongoing. But the crowd is definitely on his side, cheering him on at every hook and jab, many of whom have given their support in a petition to see the English libel laws changed. One high-profile advocate is Richard Dawkins, who recently spoke at the Liberal Party conference in England calling for reforms to the law.

The latest turn of events came on the 14th of October at the Royal Courts of Justice, where Lord Justice Laws rejected the interpretation of Singh’s article by Mr Justice Eady. Eady’s interpretation was that Singh had alleged the chiropractors were knowingly practising treatments for which they knew there was no proof of efficacy. The new interpretation is that the article was fair and in the public interest, which now grants Simon Singh the right to appeal the earlier ruling.

It’s not over yet, but there is reason to be optimistic, not only for the diminutive science writer as he stands in the shadow of a mightier adversary, but for all who see this as a fight that should be fought in open debate, with good evidence as the gentlemanly weapons of choice.

Further reading:
[Times Online] Simon Singh legal victory
Jack of Kent’s blog
[The Guardian] Science writer Simon Singh wins ruling in chiropractic libel battle

Better sound images

Camouflaged kitten2

Invisibility cloaks still belong to the realm of science fiction, but it is a legitimate field of research which frequently catches the eye of mainstream media, who then spin the usual clichés about Harry Potter technology. If it became a reality and objects could be hidden from view, you would have to resort to more primitive methods of detection, such as prodding the object with a stick. You might even consider looking for it with sound, in the same way that sonar searches for submarines or images wrecks on the sea bed. Well guess what? Harry Potter magic may put an end to that too.

To achieve optical invisibility, light is made to flow around an object like water around a rock in a stream. None is reflected from the object and light from behind it passes to the front, giving the appearance that the object is not there. Scientists have made the necessary metamaterials that can produce this effect and have made small objects invisible to electromagnetic radiation within a narrow range of wavelengths. It would be like hiding a miniature version of Harry Potter, but only when he is illuminated by blue light, but not green or red. Most importantly, the concept works and these materials promise more than just better camouflage for the battle field. Metamaterials could provide us with super lenses, giving microscopes the capability of imaging well beyond the limits of conventional optics.

Sound waves are physical and are not part of the electromagnetic spectrum, but acoustic metamaterials could do with sound what their optical counterparts do with light. Nicholas Fang and his research team working at the University of Illinois, have recently produced a flat metamaterial lens which was capable of focusing ultrasound to an exceptionally small spot size¹. It’s not yet achieving anything that cannot be done with conventional acoustics, but it lifts acoustic metamaterials from the books on theory and on to the lab bench. This science could one day provide improved imaging resolution for acoustic technology. In engineering it might detect otherwise hard to see cracks in buildings and other structures. In medicine, these metamaterials could provide major improvements for in vitro ultrasound imaging, seeing details inside the human body that are invisible to our technology today.

1) “Focusing Ultrasound with an Acoustic Metamaterial Network”, Shu Zhang, Leilei Yin, and Nicholas Fang, Phys. Rev. Lett. 102, 194301 (2009), DOI:10.1103/PhysRevLett.102.194301

2) Photo by Malingering (Creative Commons Attribution).

See also:
http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.102.194301
http://news.illinois.edu/news/09/0624superlens.html

Simon Singh interviewed

For those following the legal battle between the British Chiropractic Association and Simon Singh, you can hear more about it from Simon himself. In a recent interview on the Nature Podcast, he explains how this story goes beyond a personal legal case and that English libel laws are in need of reform. He argues that, as they stand, these laws present a serious threat to open scientific debate and free speech.

The interview is available for download here.

Hmmm.. coffee breath

I love coffee^†

The malodorous whiff of coffee breath could soon become a thing of the past, thanks to the coffee itself. New research suggests that some components in the coffee may have the capacity to stop the growth of bacteria that are the cause of bad breath.

Dr. Mel Rosenberg, a professor of microbiology at Tel Aviv University, made this discovery serendipitously while studying what it is in coffee that makes breath smell bad. He set out to demonstrate the odour produced by certain extracts of coffee in saliva, but instead discovered that that were in fact components in the coffee which inhibit the causes of bad breath.

If coffee could be engineered to produce better smelling breath, coffee lovers would no longer have to stock up on mints and gum to counter its effects. If the odour inhibiting molecule can be isolated, this research may even provide us with improved breath fresheners by actually adding a little coffee to those mints.

† Photo by rpeschetz (Creative Commons Attribution).

A new tool for Mars explorers

Sand ripples and a pavement of outcrop rock on Mars. Image Credit: NASA/JPL-Caltech.

Landers and rovers sent to Mars carry a wide range of scientific instruments for studying their environment on the planet’s surface. One can imagine them scratching at the ground beneath their feet, motors whirring and clicking to prepare and analyse samples. Cameras pan around and take in the scene, while lasers shoot into the sky to study the weather of the red planet. Now, in the search for groundwater on Mars, there is a new tool that future landers may come equipped with, allowing them to see deeper into the rocky surface than ever before.

Ground penetrating radar has the advantage that it can operate remotely from aboard an orbiting satellite, which means the whole planet can be mapped for signs of water at or below the surface, but it just can’t see far enough, particularly through rock. This is where a new electromagnetic sounding device may provide a solution.

Researchers in the Department of Space Studies at Southwest Research Institute, have built and tested the Mars Time Domain Electromagnetic Sounder (MTDEM)^†. The working device would weigh in at less than 6 kg and be operated from a robotic lander. Using compressed gas cannisters, it deploys a loop antenna by firing two projectiles, consisting of spooled up wire, as far out as 200 m.

The triangular antenna induces electrical currents in the ground which are then detected at the surface. This technique should be able sense the characteristically high electrical conductivity of any groundwater in the region, to depths far greater than can be achieved with ground penetrating radar. The researchers claim that such an instrument should be able to detect water as far down as 5 km.

It is believed that water helped shape the geology of Mars in the distant past, and it is speculated that large quantities of that water may still exist deep beneath the surface of the planet. If discovered, it will explain a lot about Mars today and in the past, but it will also bring questions, such as can we use it for human habitation of Mars and is there anything already living off of it?

† Grimm, R. E., et al., A time-domain electromagnetic sounder for detection and characterization of groundwater on Mars. Planet. Space Sci. (2009), doi: 10.1016/j.pss.2009.05.003

Back to the moon with some hard hitting science

Lift off for LRO and LCROSS (Courtesy NASA)

Like any curious boy or girl wanting to understand how something works and what it’s made of, the tried and tested method that always seems to deliver results is brute force; hitting something hard and cracking the curiosity open to reveal what’s inside. The engineers and scientists at NASA are no exception when it comes to using this primeval method and they’re heading back to the moon with something that packs an astronomical punch.

This afternoon, NASA launched the Lunar reconnaissance Orbiter (LRO), along with the Lunar Crater Observation and Sensing Satellite (LCROSS), aboard an Atlas V rocket from Cape Canaveral in Florida.

The LRO will begin its mission next week, orbiting the moon and imaging its surface in great detail, providing valuable data for the selection of future landing sites and perhaps even a manned moon base.

The job of LCROSS, in October of this year, is to smash its way into the moon’s surface. First it will separate from the Centaur rocket to which it is attached and watch as it crashes into the lunar pole, where scientists suspect water might be found. Instruments on board LCROSS will analyse the ejected material as it passes through the plumes sent up from the impact, shortly before the spacecraft itself crashes into the planet and meets its end.

The ejected material from both impacts will be illuminated by the sun and will also be studied by Earth and space based telescopes, including LRO. If we’re lucky, they may glimpse evidence of water on our otherwise rocky neighbour, a much needed resource for a moon base or any other human colony.