Locking-out Parasitic Worms in an International Lab

May 23, 2013

Spotlight on Research is the research blog I author for Hokkaido University, highlighting different topics being studied at the University each month. These posts are published on the Hokkaido University website.

Yu Hasegawa stands by the laboratory fridge in which samples of infected plants are stored.

When it came time to select a laboratory for her final undergraduate studies, Yu Hasegawa did not make an easy choice.

“I’ve wanted to study abroad for a long time,” she explains. “So when I had to choose a laboratory to join, I wanted to work with Derek.”

Professor Derek Goto moved to Japan from Australia and his laboratory, with its group of researchers heralding from Australia, Japan and Malaysia, is one of the most international in Hokkaido University.

Goto’s group is part of the School of Agriculture and its focus is a crop-destroying worm known as a root-knot nematode. The name is accurately descriptive; this minute parasite burrows into the roots of plants and sets up camp, creating a distinctive knotty bulbous growth around its new home. Such an infestation may kill younger seedlings and also decimates the adult plants to cause huge reductions in yield. Able to infect around 2000 different plant species, root-knot nematodes are single handedly responsible for about 5% of the global crop loss. In short, this is a serious world-wide problem.

With plans in mind to study outside Japan after graduation, Yu had practised English alone in addition to her agricultural studies. While it wasn’t always easy to understand what everyone was saying at first, Yu found she could generally follow the discussions of her new group. However, language was not the only change she had to deal with.

“In Japan,” Yu describes, “You have to remember facts from the textbook or you are shown how to do a task and then tested on this. Derek didn’t work like that; he would give me hints but I had to think for myself.”

This change in style was also what Yu was keen to experience when she joined Derek’s lab, but she admits it wasn’t easy.

“When I first came here, I was so confused. I was used to the Japanese style and I felt sad and angry. My friends in other laboratories were making progress on their projects but mine wasn’t going anywhere.”

Even with the help of the other members of the laboratory (who Yu describes as ‘awesome’) it took Yu four to five months to feel comfortable with her work.

While everyone in Derek’s group studies the problem of the root-knot nematode worms, each member investigates a different mechanism for stopping their destructive life cycle. Yu is examining what happens when the worm has infiltrated the root and starts to build its signature nest. In order to create the bulbous knots, the worm produces a secretion of compounds. This mix transforms the plant cells from their normal shape and function into enlarged giant cells with multiple nuclei in which their DNA is packaged. Not only are these inflated cells produced, but the cells surrounding them start to multiply, swiftly producing the knotted structure that signifies the infestation. Once transformed, the giant cells begin to suck nutrients away from the rest of the plant for the worm to gorge upon.

What Yu wants to know is which is the specific ingredient in the cocktail of compounds the worm secretes that causes the plant cells to transform. If the process could be broken down to a single biological key, then maybe a plant variation could be grown that was resilient to that one compound, effectively creating a locked door to the worm.

To investigate this possibility, Yu analyses the worm’s secretion and separates out of the mix a possible candidate for this cell deforming key. She then exposes a fresh batch of plant cells to only this single compound and watches how they develop.

Yu talks confidently about the complex procedures involved in her work and says that now, six months into her time in the laboratory, she does not feel her research is behind that of her peers.

“I think we are almost at the same level, and hopefully I can think more by myself so perhaps my ability to conduct experiments and convey my ideas efficiently in English and Japanese is better,” she adds, hesitantly.

After this year, Yu plans to pursue her dream of going abroad. She is currently applying to the Japanese Government for a scholarship to attend graduate school outside Japan. There is no denying that both in research and science communication, Yu had worked impressively hard to achieve this goal and we are excited to see what comes next for her.

The $1000 genome

May 17, 2011

The Postdoc Perspective was a blog for the Physics and Astronomy Department at McMaster University in Canada that I kept while I was a postdoctoral researcher. Many of the topics were talks presented at the McMaster Origins Institute seminar series.

My Dad has high blood pressure and my Mum had to receive treated breast cancer but what does this say about my future health? It is possible I have a predisposition to both these conditions but I may also never develop either. The difference comes down to what combination of genes I have inherited and for me to know for sure, my genome would have to be mapped.

The U.S. Department of Energy Human Genome Project Information Web site estimates it would take "about 9.5 years to read out loud (without stopping) the more than three billion pairs of bases in one person's genome sequence"^[*]. It therefore unlikely to surprise you that the mapping of your personal genome does not come cheaply. Currently, you're looking at around $50,000 - $100,000 which only seems affordable in light of the fact the first genome to be mapped in 2003 cost $3,000,000,000.

Now, however, a new technique for gene mapping is being developed that could bring the cost down to under $1000. This would allow personal genomics to become available for predictive medicine. As our Origins' colloquium speaker, Professor David Deamer from the University of California Santa Cruz, suggested, you could imagine having your own genome stored on a thumb drive to take with you when you visited your doctor.

Professor Deamer first conceived the idea for the $1000 genome over twenty years ago. He postulated that if it were possible to create a hole in a biological cell that was sufficiently narrow that only a single strand of DNA could pass through it, then the DNA components ("nucleotides") could be analysed and recorded as they were dragged through. Combined, this pattern of DNA components make up your genes^[**]. The question was what could be used to create such a tiny channel?

The answer to this did not emerge until ten years later and turned out to be a toxin called alpha-hemolysin. As its description suggests, hemolysin is not normally remotely desirable and is released during staph infections where it burrows into red blood cells and makes them explode (not good). In this case, however, its burrowing ability is exactly what Professor Deamer's team were looking for.

Alpha-hemolysin adheres to a cell's surface and makes a hole through the cell's structure known as a 'nano pore'. When a small voltage is applied, charged particles pass through the cell to create a tiny, but measurable, electric current. When a DNA strand attempts to pass through the hole, it can only just fit. This means it temporarily blocks the channel while it is squeezing through, causing the electric current to drop. The amount the current falls by turns out to be determined by which nucleotide is currently in the way. By measuring the change in current, the genome can be mapped.

The familiar picture of DNA is not of a single strand, but of the double helix. Tied up in this manner, the DNA cannot fit through the nano pore. Instead, it enters the broader, top part of the channel and get struck. From this position, it becomes unzipped until it can finally pass through the hole and out of the cell. The very exact size of the hole is important, since to record the genome accurately, only one nucleotide at a time must exit the cell.

Genome mapping using this technique is not yet available, but Oxford Nanopore Technologies have plans to produce a commercial device using this process. That being the case, there is only really one question left:

Are you ready to know what you really are?

--
[*] In case anyone is really curious, this figure is calculated by assuming a reading rate of 10 bases per second, equaling 600 bases/minute, 36,000 bases/hour, 864,000 bases/day, 315,360,000 bases/year. So there.

[**] Nucleotides make up DNA strands and stretches of DNA strands make up genes (in case anyone else was confused about the order of the extremely small).

Networks in the brain

May 2, 2011

So your friend Ben is married to Margaret who is friends with Rachel who shares an office with Rory who worked on a planetarium show with Rob who once received a detention at school for mooning Prince Harry [*].

According to the theory of the six degrees of separation, you are no more than half a dozen people away from receiving that front row invite to the Royal Wedding. The idea is that you are connected to every other person on Earth through an average of six people. It is a concept huge social network sites such as Facebook have been testing, but surprisingly it is an arrangement that is reflected in the structure of your brain.

All this I learned at the Royal Canadian Institute (RCI) 2011 Gala. The RCI was formed in 1849 by Sir Sandford Fleming. One of its original roles was to publish a scientific research journal in Canada but now its emphasise is on a weekly public lecture series which covers a wide range of scientific topics. In addition, the RCI helps with grants for students wishing to study science at university and it hosts an annual Gala dinner. The Gala is an opportunity to have a discussion over a great meal with a scientist. One of the twenty five tables at this year's event was hosted by my adviser, Professor Ralph Pudritz, but I shunned his table in favour for one led by a scientist working on the structure of the brain; a topic I knew nothing about. (When I told Ralph I'd rejected his table in favour of another he assured me he 'expected nothing less'. I don't think he meant this to be a reflection of my attention in our research group meetings.)

Our table was led by Professor Mark Daley who worked on models of the brain at the University of Western Ontario. When newly arrived at his institute, Mark explained that he had known very few people.

"But, I did know Mike." He gestured towards one of the other diners seated with us. "And Mike knew everybody. So if I needed to contact somebody elsewhere in the University, I could go to Mike and the chances were he knew them. This meant although I only knew a few people, I was connected to almost everyone else via only one person."

This, Mark explained, was the premise behind the six degrees of separation. There are a few people who know a huge number of others and these individuals act like hubs. People preferentially attach themselves to hubs (since the hub is likely to meet them through their enormous list of contacts) resulting in them being connected to a great many others through a very small number of steps.

What Mark said about Mike turned out to be entirely true. When chatting to him before dinner he had declared, "Oh, you're at McMaster! Do you know Hugh Couchman and James Wadsley?" I had to confess I did.

Mark continued by explaining that the brain organises its neurons along similar principals. There are hub areas in the brain which have a huge number of neurons connected to them and these link up regions which have sparsely few connections.

This structure can be explored with two major methods. The first is to take thin slices of the brain's grey matter and the second (more desirous for live volunteers) is to watch water flows via an MRI scan.

The consequences of this neural structure have important ramifications both for the effect of brain-damage and in understanding mental illnesses. Damage to one of these hub region, for instance, can result in the head injury being fatal because the brain simply cannot rewire to compensate from such a large loss of connections. Other times, the damage can be severe but limited to one specific area. Mark cited an example of a woman with damage to one hub who was left unable to see.

In most people, the number of hub regions is small and they are found is quite specific areas. One exception to this is in the case of people suffering from schizophrenia, where many smaller hub nodes are seen and in farther flung areas in the brain than for a healthy person.

A question I asked was whether this was the underlying concept in electric shock treatment for depression? Was the idea to try and forcibly rewire the neurons by destroying their electrical signals and thereby forcing the brain to choose another (hopefully better) structure? Mark said that while this was the correct premise, such treatments were now strongly out of favour. He compared it with chemotherapy, saying you effectively killed a lot of neurons in the hope that you destroyed the bad pathways before you took out all the good. He did describe less invasive treatments which included asking the patient to think of something pleasurable directly after thinking of a traumatic event. Over time, the association can force the brain to rewire and help with post-traumatic stress disorder.

So what is is that governs our thoughts? Is the brain, as Penrose claims in 'The Emperor's New Mind', a system governed by random probabilities via quantum mechanics? Or are we, as Mark assumes in his work, simple Turing machines whose thoughts and actions can be completely predicted based on our experiences? Neither sounded particularly appealing.

"I want another option," I told Mark. He nodded and promised me one after he'd finished his dinner. The problem with being the guest speaker at a meal was the actual food was hard to fit in amidst the barrage of questions.

The third option, he explained as the plates were cleared, was that our mind is like a Bayesian machine which using a mixture of probabilities and input from its surroundings to make decisions. So when faced with the delectable crumble for desert, there was a very high chance that I would take the logical choice and eat it. Then there was the small probability I'd lob it across the table. I love feeling I have choice.

The crumble was rhubarb, in case anyone was wondering.

At the end of the dinner, each table was allowed to pose a question to another group to allow diners the chance to hear about the different areas being discussed that evening. The most important question was posed first and was directed at Professor Jeffrey Rosenthal from the department of statistics at the University of Toronto:

"What is the probability that Kate Middleton will wear a slinky wedding dress?"

"Slinky?" Jeffrey rose to answer the question. "This isn't as close to my area of expertise as you were led to believe!"

--
[*] Editor's note: any resemblance to real people, in the Physics and Astronomy Department or otherwise, is purely coincidental and Rob has never yet admitted to knowing Prince Harry. Or mooning.

Black hole menu

April 9, 2011

It is a depressing fact that over 95% of the Universe can't be bothered to interact with you. By looking at the speed with which our galaxy is rotating, we can infer that the amount of mass present must greatly exceed what we can see in stars and gas. This 'dark matter halo' is the cocoon in which our brightly lit spiral galaxy lives.

One of the puzzling features of these galactic cocoons is their wide range of sizes. It is surprising because the size of a galaxy is proportional to its dark matter halo, yet there are no galaxies found in very small or very large halos. It's a little like looking at the cities in Ontario, and finding everyone lives in Hamilton or London, but there is not a soul to be found in Toronto or Ancaster. Additionally, the large galaxies that do exist tend to have predominantly old stars, with very little cold gas from which new stars could form. So, in our Ontario analogy, Ottawa would be populated only by people over the age of 65.

The absence of small galaxies in small halos is explainable by the violent deaths of stars. As a star such as our sun reaches the end of its life, it will throw a large fraction of its substance into the surrounding area in an explosion called a supernova. In a small galaxy, this can blow so much gas out of the halo cocoon that it destroys the galaxy, leaving behind a star-less dark matter halo.

The absence of very large galaxies in the biggest halos however, is more of a mystery. The amount of mass in these galaxies would be so large that any gas that is ejected away from the disc by supernovae will be dragged back down by the gravitational pull of the remaining matter. In the last Origins talk of the semester, Professor Tim Heckmen from John Hopkins University in Baltimore proposed that the answer lies with super-massive black holes.

The most sinister objects in the Universe, a black hole is where so much mass has been squeezed into such a tiny volume that the speed needed to escape its gravitational pull is greater than the speed of light (and that's the fastest speed there is!). For the Earth to become a black hole, it would have to be compressed down to the size of a grape. Super-massive black holes containing the mass of billions of suns, reside at the centre of galaxies. How they have formed is hotly debated but what is known is that the larger the galaxy, the larger its super-massive black hole. Of course, something that destroys everything that enters it does not have the best PR, so going to these objects for answers feels like asking a kraken to attack a single ship; the probability of having any vessels left at the end of its foraging seems rather low.

Professor Heckman's theory is that gas close to the black hole is pulled towards it like water swirling down a drain. As it approaches the edge of the hole, the energy the gas is loosing (by dropping down the black hole-drain) is converted into heat at a rate that is much more efficient than nuclear fusion. The resulting radiation is the most intense source in the Universe. If enough gas falls in, the black hole can go through a 'feeding frenzy' and produce jets that evacuate huge holes in the galaxy. These jets fill the halo with hot gas, removing all the cold star-forming gas from the disc. If the jets are strong enough, the galaxy could be destroyed completely. If it isn't, then the resulting cavity around the black hole removes its food supply and the jets turn off. Yet, as the ejected gas cools, it falls back down to the galaxy, serving up another black hole dinner.

Why though, would this mechanism not occur in our own Milky Way, destroying us and smaller galaxies along with the bigger ones, kraken style? The answer, Professor Heckman explains, is that the super-massive black hole needs feeding with a lot of gas to produce the powerful jets. One possible source of this food is from supernovae as they blow away their outer layers. This gas might initially go into the halo, but as it returns to the galaxy, it could be drawn into the black hole which would then start to feed and produce jets. Larger galaxies will have more stars and therefore more supernovae, increasing the food supply to a point where jets can be formed. This means that the lifecycle and star production of a galaxy is intimately linked to its super-massive black hole. To understand one, Professor Heckman said, you need to understand the other.

At the end of the talk, there was one important question on the audience's mind:

Which came first; the black hole or the galaxy?

Sneaky little hobbitses

March 22, 2011

Despite what you may have claimed over coffee this morning, 18 million years of evolution separates your landlord from a gibbon. If it's any consolation, he's only about 5 million years from a chimpanzee. After that time, our own branch of the tree-of-life evolves through a series of distinct 'hominids' before producing grad students.

But who were our ancestors and what did they look like? Is it possible to distinguish them from other branches of the ape family tree?

This was the topic of today's Origins Seminar, given by Dr Dean Falk from the School for Advanced Research in Sante Fe, New Mexico. Dr Falk is what is referred to as a 'paleoneurologist', a peculiar sounding term for someone who studies fossilized brains. Ancient remains of mammals can have a cast of their brain (known as an 'endocast') preserved via sand and other debris filling the cavity between skull and tissue. This hard coating is protected from weathering by the fossilised skull which slowly wears away, leaving the natural endocast in its wake.

The process of analysing an endocast is not an easy one since it is only an imprint of the brain's surface, so no internal information regarding the neurons or chemical structure is preserved. However, by comparing endocasts from humans and apes with those from ancient remains, much can be learnt about our own evolution.

Of course, it does help if the ancient remains you are studying are not fake. A famous example of this situation is the "Piltdown Man". Discovered in the UK in 1912 in Piltdown, East Sussex, these fossilised remains were exposed as a forgery in 1953. Rather than being the missing link between humans and chimpanzees, this skeleton was created from a human skull attached to an orangutan's jaw. The teeth had been filed down and the bones stained to look like a single specimen. In part, its success as a hoax was due to it fitting in with the preconceived idea that a measure of evolution was the brain-case size; the prevailing belief was that brains became bigger first and the rest of the body, including the jaw, changed afterwards. The discovery was also pleasing to local scientists who embraced the idea that the first human was an Englishman!

In reality, however, the first hominids were found in Africa. Ten years after the 'discovery' of Piltdown Man, Raymond Arthur Dart discovered the remains of the 'Taung Child' in South Africa; a fossil dating back 2-3 million years. With its small ape-sized brain and location far from England, the Taung Child contradicted everything seen in the Piltdown Man, making it a controversial discovery. Dart examined the brain endocast and concluded that, while the brain was relatively small, it was advanced due to its structure. In particular, he identified two groves whose positions matched those found in humans but not in apes.

Ultimately, Dart's analysis was proved to only be partially right, but the technique of examining the position of the brain's major groves (sulcal patterns) is the main way of differentiating hominid brains from our ape cousins. These differences come about as regions of the brain that were previously separated become more interconnected in humans.

Interestingly, our own ancestors were not the only bipedal species walking around Africa 300 million years ago. Paranthropus are thought to be an extinct hominid species, unrelated to us. Their brains were characterised by a prominent central ridge from which strong jaw muscles would have been attached. Our relatives were the Australopithecus africanus, of which the Taung Child is an example. The migration and spread of A. africanus is thought to be north out of Africa and then into Europe and Asia. This has been called into question recently, however, by the discovery of a hobbit.

The announcement of the three feet tall hominid remains found in Indonesia came in 2004. The attractively named, "Lb1" was female with very short legs and therefore seemingly disproportionate long arms. Her feet were genuinely long, stretching a length equal to the distance between her knee and ankle. The remains were found with primative tools, similar to those found in Africa, and she would have lived alongside giant Komodo dragons, which is a slightly unnerving prospect for someone only three foot high.

At 417 cubic centimetres, Lb1's brain was chimp sized but the endocast revealed advanced features reminiscent of a human over an ape. Her discovery opens many questions, with schools of thought differing over whether Lb1 can be a new human species from our ancestry when her brain is small and she was found so far from the picture of migration out of Africa.

One thing that appears to be clear from the endocast discoveries is that brain evolution can occur in many different ways. It is possible to rewire and reorganise our grey matter without it becoming larger. This leads to different combinations throughout the fossil history; a difficult challenge to place in logical order. So in short, size does matter, but it's not just about how much you've got. It's what you're doing with it that counts.

Can you build a transmitter?

March 9, 2011

"You claim that there are many Earth-like planets while finding none!"

"But we have found many Jupiter-sized planets and they should be rarer than Earth-sized so the trend is pointing towards a large number!"

I was sitting in the audience of "The Great Extraterrestrial Debate", an event hosted by the Centre for Inquiry in Toronto. It was part of the organisation's "Extraordinary Claims" campaign which is designed to put some of today's most controversial allegations through a critical examination. This evening's topic surrounded the likelihood of alien life interacting with us on Earth.

The debate comprised of a panel of three individuals whose profession gave them a stake in this field. The first was Astrophysics Professor, Ray Jayawardhana, from the University of Toronto, whose research focusses on planetary formation outside our Solar System. The second was science fiction author, Robert J. Sawyer, and the third was Seth Shostak, a senior astronomer at S.E.T.I. (Search for Extraterrestrial Intelligence) Institute.

Despite being labelled a 'debate', it was stated upfront that all three panellists were in agreement; to this date, there has been no strong evidence for life outside of Earth. That said, the three unique view points being brought to the table did lead to passionate discussion. The above snippet was between Ray Jayawardhana and Robert J. Sawyer and was wrapped-up by Seth Shostak who pointed out:

"Ray and Rob arguing shows how hard it is to find stupid life. If they can built a basic radio transmitter (and you should all ask yourself now if you can do that) then their biology doesn't matter!"

Apart from the thinly veiled implication that S.E.T.I. would not count most of the audience as 'intelligent life', Dr Shostak's point highlighted a fundamental difference between his work and that of many astrobiologists; S.E.T.I. is only interested in life-forms that can talk to us. This bypasses all the problems with defining what life is and how we should go about detecting it when it is likely to be nothing like our own (a problem previously touched on in this post).

But is it really likely that we will make contact with aliens who can communicate with us?

Seth Shostak and Ray Jayawardhana both discussed the recently launched Kepler mission which is uncovering a flood of planets, with 1235 possible candidates identified in the first year of operation alone. This is in comparison to the 500 planets that have previously been discovered in the last 15 years. This huge influx of data in such a short time indicates the vast number of planets there must be in our galaxy which suggests that it would be a miracle if we were the only life to have been created on any of them. Dr Shostak also added that S.E.T.I.'s current failure to find life should not be interpreted as an absence of extraterrestrial intelligence. Currently, S.E.T.I. has only searched a tiny patch of the sky and declaring the Universe baron of life based on such a survey would be the equivalent of searching a square kilometre of Africa and concluding there were no elephants on the continent.

On the other hand, even if life did evolve on another world, we might have a problem with timing. Robert J. Sawyer made the argument that while the human race has existed for a few thousand years, there is a much narrower window between the invention of radio (needed for communication with S.E.T.I.) and the creation of the atomic bomb. It could be that almost as soon as a life-form can communicate, it self-destructs. Dr Shostak counted this by stating that the invention of rockets would take place in the same time-frame to launch the bombs, which gave the possibility of members of the species leaving the destroyed planet behind them to colonise somewhere else. He suggested that, like cockroaches, a life-form such as humans would be impossible to fully wipe out.

So ... if you're not able to build a transmitter, S.E.T.I. consider you too stupid to be interesting. If you ARE able to build a transmitter, you are analogous to a cockroach. Everyone feeling good? Then I'll continue...

Then there is the problem that if aliens were to appear, how would we react? Contrary to popular movies, it was deemed unlikely that such a discovery would cause rioting in the streets. For one, the signal would be coming from so far away that it isn't going to affect your ability to buy your morning coffee from Tim Hortons any time soon. Secondly, 1/3 - 1/5 of the population believe aliens are here already doing (and I quote Seth Shostak) "experiments your mother would not approve of", so a significant fraction of the world would not even be surprised.

Robert J. Sawyer suggested that it might be unhealthy for our own future to discover a more advanced life-form. If it could be shown that most life did survive their 'technological adolescence', then the human race might not strive as hard to solve its own problems, being content to let time take its course. Dr Shostak took this idea to a more personal level by saying that tenured professors might find it depressing to know all their scientific research had been solved a million years ago by this advanced alien race. Professor Jayawardhana, however, seemed to think this would save on having to publish more papers!

Finally, Robert J. Sawyer pointed out that S.E.T.I. did make one very big assumption:

That life, if it's out there, would be remotely interested in us.

An eye to the sky

February 16, 2011

Altitude sickness, the safety liability waver form told us, was unlikely to be severe below 3000 m. At 2715 m, the location of the Gemini South telescope in the Chilean Andes should be fine for most visitors but if it wasn't, we were commanded to mention it to observatory personnel. The two hour drive down the steeply descending narrow dirt track from the mountain top was not the place to make mistakes.

When the observatory heard our plans to accompany Gemini Fellow, Dr Michelle Edwards, on a tour of the telescope, they suggested this could be counted as an official visit since many of our group were astronomers. Such listing would enable us to stay on the mountain for longer if we wished. Michelle explained that three non-astronomers were also attached to our party but it wasn't until she added that a theorist was also present did Gemini write the whole idea off and give us tourist passes.

Set on the foothills of the Andes and backing onto one of the driest deserts on Earth, Gemini's position in Chile is an ideal location for astronomers to study the southern sky. The domes of three telescopes could be seen as we ascended the mountain. The 4.1m Southern Astrophysical Research Telescope (SOAR), the Blanco 4m telescope and our destination, the 8m Gemini South.

Half-way up the mountain is a look out point with three slender metal tubes mounted on the stone wall. These resembled smaller versions of the instruments we were going to see but in fact proved to contain no magnifying lenses and were just used to guide your eye to the appropriate glittering silver hemisphere. Strangely, one was pointing at an entirely empty space which turned out to be the planned site for a new telescope, the Large Synoptic Survey Telescope (LSST).

Gemini, as its name suggests, is one of two identical telescopes both with primary mirrors that are 8m in diameter. Its twin sits on the dormant volcano, Mauna Kea, in Hawaii where it points towards the northern sky. Currently, the governments of the USA, Canada, UK, Chile, Argentina, Brazil and Australia share Gemini's operational costs to enable their astronomers to observe at the two sites.

It was swelteringly hot when we reach the mountain top, but the inside of the Gemini dome is cool. It is important, Michelle explains, to keep the inside temperature to approximately what it will be at night when the dome is rolled back to expose the telescope to the night sky. If this isn't done, the hot air rises out of the dome and over the aperture to create a phenomenon known as 'dome seeing'; the distortion of an image from turbulence due to the hot air rising. This turns the telescope's sharp view of the stars into fuzzy blobs, a waste of the excellent view the observatory has from the mountain top.

The huge mirrored dish of the telescope is supported high above us as we stand at the telescope's base. Its silvered surface is refreshed every five years by a large saucer-shaped device that is stored in the observatory's basement. The story goes that when this equipment was delivered to a port in Chile, the locals believed it to be a discovered UFO.

Climbing up the blue frame work, it was possible to peek under the mirror cover and see the surface that would, in another 8 hours, be pointed at the heavens. This giant star-studying cyclops made my eyes seem weedy by comparison.

Over to the far right was Gemini's newest tool; GeMS, a five beam laser guide star system. Stars 'twinkle' because the Earth's atmosphere is distorting the star light, an effect that is much worse for an 8m telescope than for your 1inch eyeball. To compensate for this, a system called 'adaptive optics' was developed that allows the telescope's mirror to deform depending on the atmospheric conditions to produce the best possible image. These adjustments can occur at a rate of 100s of times per minute. To measure what changes the mirror should make, most telescopes use 'guide stars'. These are stars of a known brightness that show minimal variations and can be used to calibrate the system. Gemini's new instrument goes one better than this; by firing lasers up at the sky, they can build an extremely accurate picture of how the atmosphere is distorting the light over a very wide area. While four guide stars are still needed, they can be much fainter objects and an area of the sky 2-3 times that of traditional adaptive optics systems can be 'corrected' for in a single measurement. This allows for far sharper images, especially in crowded areas of the sky --for instance near the galactic centre-- where locating a reliable, bright guide stars is difficult.

Of course, shooting light up into the sky does come with some associated risk to other, non-celestial, objects that might be in its path. If care is not taken, the laser beam could blind either an aircraft or a spy satellite.

The latter, ladies and gentlemen, is an act of war.

The average observing run tries to avoid such inconveniences by co-ordinating the times they wish to use the laser system with US space command (totally didn't make that name up). They then receive a list of times they may not use the laser system in particular directions.

Avoiding aircraft is a less sophisticated business. Although in theory, the flight paths and times of planes are known, this information is not accurate enough to be used. Instead, 'spotters' are employed to stand in regions close to the telescopes with a device like a hula hoop with which they can estimate the distance to the plane and whether the laser system will pose a risk. When an aircraft approaches, the spotters can contact the observatory and ensure the lasers are not being used.

This ... advanced ... aircraft detection technique that is apparently used by million dollar telescopes all over the world seemed so completely implausible that I demanded its verification from both Michelle and two other observers who were in our group. Their stories were consistent. I decided no observer was ever in a position to criticize an approximation I made in my simulations ever again.

(Left image is the Gemini dome, top right is SOAR and the bottom right is the view over the mountains. Many thanks to Michelle for taking the time to proof-read this piece!)