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Going a long way to do a quick data collection.

Like many a scientist before me, I have spent this week trying to grow a crystal. I wasn’t fussy, it didn’t have to be a single crystal – a smush of something would have done – just as long as it had a bit of long-range order. But no. Hours spent staring at a screen as the sample I wanted to study failed to sort out its atoms into something I could work with.

Look it is pretty, but it’s not the crystal I was looking for. Author

Sitting, staring at an experimental failure rather does make you think about and question many things. Moving on from the ‘why did I have this stupid idea in the first place’ (which is a bit of a running theme in weeks like this), you try and put your experiments in context. I’m leaving Japan tomorrow, with a stack of lovely fresh data (and probably some excess baggage fees). Some of my experiments worked, some didn’t - that’s the nature of the beast. No amount of planning and preparation for my three months here would have probably changed that.

Actually three months of experiments (or at least access to equipment) has been a massive luxury for me. Most of my data collections are from central facility instruments, like those offered at the Australian Synchrotron and the Bragg Institute. Access to these instruments can take a lot of preparation, starting with a peer-reviewed proposal. Then, if you’re fortunate enough to be granted time; months of planning, risk assessments and gathering of equipment go into perhaps 24 hours of precious time on the instrument of your desire.

But what if you’ve put in YEARS of planning, and then had to wait YEARS for a tiny window of results? What if, rather than heading to Japan, you’ve had to journey to Pluto for them? How excited would you be that your tiny window of observation was just coming up? It’s a good job I’m not on the science team for New Horizons, as I couldn’t quite image how I’d sleep from now until July.

How far away is Pluto. Very. Image taken from NSW, Australia Andy Casely

I feel a bit of affinity with New Horizons, as we’re both about the same amount of time into our research careers (after probably a similar amount time of building/planning for New Horizons and growing/educating for me). When it launched in January 2006 I was few months into my PhD, and at that point I probably felt that I was being propelled at nearly the velocity New Horizons' was.

New Horizons did get to see a bit of the solar system on its journey, in 2007 while winding up it’s speed in a gravity assist orbit, it did a tour of Jupiter. There it took some rather wonderful images of the gas giant planet and it’s rings, and even caught an eruption of the Tvashtar volcano on Io. But since then it’s largely been in hibernation, waiting for 2015 for it’s time to shine.

Jupiter&Io.jpg
"Jupiter&Io" by NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Goddard Space Flight Center - http://www.nasa.gov/images/content/201781main_PIA10102.jpg. Licensed under Public Domain via Wikimedia Commons.

(I, on the other hand, have not been asleep since 2007 I should point out!)

When New Horizons reaches its closest approach to Pluto some of its instruments will only have a matter of hours to observe the surface of the icy dwarf. How do you possibly prepare for a window like that? Well we have some idea, ESA’s Philae lander had a similarly restricted timeline and like New Horizons' years of planning from vast teams of scientists and engineers will have gone into the small observation window. Even once the observations are done, planned down to the seconds, it will be a nervous wait for the results. Not wanting to waste a second of observation, New Horizons will wait until it is past Pluto to send its data bounty back to Earth, a process that will take months after it has flown by.

But, like for me in Japan, the Pluto flyby will only be a step in New Horzions science journey. From there it will continue to fling its way out of the solar system and the hope is that it will encounter a number of other Kuiper belt objects. We really don’t know much about the whole class of icy dwarf planets, and for me the excitement lies in what new icy geology is there to be explored. I can’t wait to see what materials and in what situations New Horzions turns up on the surface of Pluto and its moon Charon. That’ll be the start of my next (hopefully more successful) experimental adventure.

Why I’m proud to be a crystallographer

This year I have learnt more that it is probably healthy to know about crystal structures. I’ve learnt how you can turn a rabbit green with a protein, read up on French military history and marvelled at how a crystal structure can destroy itself. I’ve even found cement interesting!

When looked at the right way, even cement can be beautiful. This is the crystal structure of tricalcium aluiminate, a vital mineral in cement.

These examples are just the tip of the iceberg, or (to put more appropriately) merely the surface layer of atoms of the science of crystallography and what it has achieved. It’s been a pleasure to discover so much about the field this year.

Why? 2014 was sanctioned by the UN to be the International Year of Crystallography (along with farming and family – or was that family farming?). A definite improvement on last year’s “International year of Quinoa”, but as we loll into December I reckon there’s a few of you out there still scratching your head as to what it’s all about?

Crystallography is the science behind structure, of knowing where your atoms are. There have been some excellent “explainers” already on The Conversation, and a number of videos explaining it.

To date, across the various databases, there’s coming up to 1 million crystal structures that have been determined. That’s nearly a million times a researcher has collected a diffraction pattern (like von Laue did to kick off the whole field in 1911) and interpreted how this could be generated from an arrangement of atoms (like Bragg did in 1912). In an effort to highlight just 365 of them, myself and 40 other researchers, have blogged about one every day. I’d urge you to look over the Crystallography 365 project to see the massive diversity of science that crystallography encompasses.

But why be a crystallographer?

I don’t usually like giving myself a “scientific label” – I have a degree in planetary science, a PhD in physics and my first job was in a chemistry department. I promise you (and my parents) that it did all make some sense at the time. But one thread has run through all of these career twists, and that’s my use of crystallography.

You’ll not find many scientists who call themselves just “crystallographers” and that’s because (as my career to date shows) it’s an inherently interdisciplinary science. Most of us are something else as well, be that geologists, chemists, physicists or biologists. As a scientist starting out, that really appealed to me. I have taken my crystallographic skills, mostly learnt during my PhD in physics, and applied them to problems in fields diverse as forensics, minerals and explosives. I’ve even collected a diffraction pattern of cocoa butter!

My particular crystallographic hero, Kathleen Yardley Lonsdale - who told us that the benzene molecule was flat.

Then there are the role models. In science, as a rule, there are not usually all that many female role models to look up to. But crystallography smashes that out of the park. From Lonsdale to Hodgkin to Megaw to Franklin, women have been front and centre in some of the biggest leaps in crystallography and the community still retains its healthy gender balance.

It’s not just the crystal structure that you can get from these studies, but a very fundamental view of the properties of the material that you are looking at. As a result, crystallography has brought about some of the most famous scientific leaps, 28 Nobels have been awarded through its application. Knowing where the atoms are in materials brings fundamental insights that have revolutionised our world, from the structure of DNA to giant magneto-resistance.

Crystallography is also often at the forefront of “movements” in research. For instance, big data is old news in crystallography, with institutions like the Cambridge Crystallography Database Centre (custodian of a database of over 600,000 crystal structures, mostly of molecular compounds) set up to collate molecular structural information and “mine” that to discover new interactions and even predict how new materials will form.

There’s an argument that much of the success of crystallography has been that it is an inherently “open” science. Most of the software tools that I use day in day out are freeware – developed and maintained by researchers in the field. I’m supremely grateful for their hard work, making tools that are essential to a wide range of scientific projects, with often only citations as reward. Added to this data depositories (such at the Crystallographic Open Database) and standardisation of format have meant that scientists across disciplines can easily communicate their findings to each other.

So every time I collect a diffraction pattern, I enjoy the fact that I’m part of a collective of people (and one robot on Mars) doing the same thing. It’s a fabulous “clan” to belong to, and that’s why I’m proud to be a crystallographer.

US plans to answer the lure of Europa

To planetary scientists Jupiter’s icy moon Europa is a Siren, calling out to them across the solar system. With its youthful surface, abundance of water and the tantalising evidence of a moon-wide ocean – it is one of the best chances for us to find life within our solar system. Last week the Europa Clipper mission won some critical support of US congress representatives, who attended a meeting organised by the Planetary Society called ‘The lure of Europa’.

Can you hear it calling you? The beautiful surface of Europa. NASA/JPL/Ted Stryk

But it hasn’t been ‘plain sailing’ for the Clipper mission. In 2013 the planetary science community gathered and put out a decadal plan, citing the exploration of Europa as one of its highest objectives. However, cuts to funding for ‘outer’ planetary research in favour of Mars and the manned space program left many dispirited. The community have powered on, investing energy in lobbying policy makers, and now traction for the Europa mission is building.

So why go back?

Just in the past year there have been two remarkable insights made about Europa, only making its Siren call louder. The first of these was that the Hubble Space Telescope spotted evidence that geysers were shooting up into space from the moons surface. This immediately put Europa in a rather elite category of planetary bodies, ones that we have observed to be doing things! Now along with the ‘Tiger Stripes’ of Enceladus, sulfur volcanoes of Io and magic islands of Titan – the geysers of Europa show that this moon is more than a passive snowball.

The second insight has been a paper that did a ‘reverse jigsaw puzzle’ study of Europa’s surface. Since the Galileo mission returned it’s startling images of the surface of Europa, the features that were most obvious were extensional. Analogous to the mid-Atlantic ridge, these features were interpreted to be extending the ice crust.

The issue was, though, that nobody could see where the crust had contracted to compensate for this. Putting aside the thought that Europa had just got bigger, a recent paper has picked up on a number of lines of evidence for subduction on Europa. On Earth, subduction is one of the main ways the giant plates of crust are destroyed, with one plate being forced under the other. Among the evidence that was picked up from the Galileo images – was the mismatch of features on the surface, leaving the researchers to identify the missing ‘pieces’ of crust that had been pushed under.

Finding the missing pieces of Europa’s crust, this image shows the tectonic reconstruction of part of the surface. NASA/JPL/S. Kattenhorn

Both of these insights have highlighted the fact that Europa’s surface and interior are linked and there are ways and means that material can be brought to the surface from the interior and vice versa. There’s not proof yet that this would extend to the potential ocean below, but it’s tantalising that maybe it hasn’t been locked away from outside influences.

For me, Europa has currently lured me away from home in Australia to Japan. For the next three months I’ll be based at the University of Tokyo where I’m currently recreating bits of Europa in the lab, using high-pressure and low temperature equipment. Chiefly what I’m interested in, is how possible impurities from Europa’s sister moon Io could effect water-ice under these conditions.

Will Clipper be scooping up the Europan surface to investigate the ice crust and its impurities directly? Sadly not, there are no plans for a lander in the Clipper mission. This is mostly because we don’t have good enough images of the surface to plan this yet. But the fly-bys that are currently being planned for Clipper would add greatly to the potential of this happening, with audacious plans to have a lander that could then burrow through the ice.

The Europa Clipper probe, zipping past the icy moon NASA/JPL

But until about 2020, when the hope is that Clipper will launch towards the Jupiter system, there’s a lot of time for me to do experiments yet!