Jan 282015

Just before Christmas I had a couple of days off work and planned to give Elite a proper play, but then something happened: a friend very kindly bought me a copy of Kerbal Space Program. I knew of the game and I’d always been curious, but I assumed I would quickly get bored of a predominantly sandbox experience. Apparently I was wrong – I booted it up one morning and spent the next three days solid engrossed in orbital mechanics, staging, lander design and “delta-v”.

The game involves building rockets and space planes from a huge variety of components and launching them into space to explore the solar system (different to but based on our solar system, which I guess stops people nitpicking about accuracy), while using reasonably realistic physics. As such, it was humbling as a self-confessed science/space nerd that it took an hour of failures and a tutorial before I managed to get a rocket into orbit. It’s refreshing to play a game that pays so little attention to traditional ‘gaming’ experience and relies so much on a knowledge of physics.


A brave Kerbal on his way to the moon

There are three different game modes – sandbox mode where everything is available, “Science sandbox” where new parts are unlocked by doing new things and using scientific instruments, and a full career mode which also adds money earned through contracts. I was warned that the career mode was really hard, so I went with Science mode. This lowers the learning curve of Sandbox mode by introducing new components slowly, while removing the stress of money and crew management. The game is still in Beta but when it’s done I’ll have a stab at Career mode now I vaguely know what I’m doing.


This little guy can’t get home. I’ve reclassified him as Moon Base 1

I was struck by the familiarity of my progression during the first few hours compared to the real space programmes, and the real sense of accomplishment that I’d not felt in a game for years:

  1. Fire a rocket up into the air. Heh, this is cool.
  2. Fire a rocket up into the air and parachute the capsule back home. First successful mission.
  3. Blast well into space before splashing down in the ocean. Sub-orbital space flight!
  4. Making it into orbit (eventually) and safely de-orbiting. Ooh, reentry looks cool.
  5. Getting into orbit, firing off towards the moon, slingshotting round the back and getting back home again. Landing there looks tricky!
  6. Getting to the moon, going into obit and landing on the surface in one piece. Having no fuel left for the return journey (real-life thankfully skipped this stage).
  7. Landing on the moon, grabbing surface samples, getting back into space and making it back in one piece for the first time. A real accomplishment!

About to ditch the last stage and deploy the parachutes for splashdown

Each stage presents new challenges and physics concepts to master. Getting into space requires staging (jettisoning empty fuel tanks and engines to make the rocket lighter). Obtaining a circular orbit needs an understanding of the apoapsis and periapsis orbital nodes (farthest and nearest points) and how burning at one side of the orbit only affects the other side. And then you can worry about orbital transfers to get to other moons and planets.


Get used to the view, son, you’re stuck on Eve for the forseeable future…

Thankfully the game provides a great maneuver planning tool. The current orbits of all bodies and ships are shown, and you can add planned maneuver nodes along the path. Drag the node in each of the six directions (prograde and retrograde, normal and anti-normal, radial and anti-radial) and the predicted path updates, including closest approaches to other bodies and ‘encounters’ (getting within their gravitational sphere of influence). While I’m sure NASA use complicated maths to plan their paths, in this game dragging nodes around until you hit on something useful also works while you’re getting the hang of what each direction does to your orbit. Then you just follow the directions on your control panel to carry out the planned burn.


The aerodynamic model is very simple, otherwise this rover and sky crane would never get off the ground

 After that the sky is, indeed, the limit. I’ve got “small colonies” (read: failed return missions) on Eve (Venus) and Duna (Mars), and used a sky crane to drop a small rover on the moon. The other planets require even more powerful rockets to reach, and as we speak there are probes scouting the outer planets for my future (probably suicide) missions…

And finally, for the truly brave, there is the small matter of orbital rendezvous and docking. Why get just one spacecraft where you want it to go when you can get two in the same place, at the same speed, at the same time? Building substantial space stations requires launching them in multiple sections, and this is my next project. My first and only successful docking took an hour, but it must get easier. I mean, it’s complicated, but it’s not rocket science.

Jun 132014

Chestenham Science Festival is quickly becoming a must-attend event in my calendar. This year I went down for the Friday and Saturday with my wife and we attended half a dozen events. From my limited experience I think you could pick any event at random and be almost certain to hear something fascinating. Here are a few of this year’s talks.


Rebuilding Our World From Scratch

If 99.99% of the population was wiped out tomorrow, how would we survive as a species? What could we do to restore our way of life as quickly as possible, hopefully skipping that whole Dark Ages thing?

Lewis Dartnell opened by showing a standard pencil, one of the simplest products you can imagine, and saying that no single person in the world can make that pencil. You need to grow the trees, cut the wood, mine and shape the graphite, mine and smelt the metal for the eraser holder, and acquire the rubber. The knowledge is spread over many specialists all over the world.

He has written a book (as he kept reminding us) that tries to explain how to rebuild as much as possible of our way of life, starting from first principles (and the decaying remains of our current world). This includes starting a fire with a 9V battery and some wire wool, repurposing alternators to generate electricity, and building a gasifier from tin cans to extract gas fuel from wood.

An interesting idea is that the printing press is one of  the most vital technologies to rediscover early. Without it, information can’t be easily distributed and remains in the hands of the powerful, hampering progress. Similarly photography is great for passing on information, and can be achieved with fairly simple technology.

Other topics of the book deal with agriculture, time of day and basic chemistry. I thought there was a bit too much time spent trailing the book at the expense of actual content in the talk, but it was quite interesting. Find out more here.

 The Science Of Cake

With the lure of baking, science, explosions and free cake samples, how could we resist? Henry Herbert of the Fabulous Baker Brothers was joined by chemist Andrea Sella and material scientist Mark Miodownik for some live baking action, interspersed with plenty of explanations about exactly what’s going on in your mixing bowl.

Why does egg go white after whipping? It’s all to do with refraction from the tiny air bubbles, bending the light in all directions until it’s opaque, and in fact this follows the same principle as to how sun cream works.

Does egg whip up quicker in a copper bowl? Yes it does, because the copper ions bind to the proteins, stabilising the foam (and making it taste foul is the process).

Why are some things sweet? Nobody really knows, because many completely different shaped molecules taste sweet, including some that are quite dangerous. Ever wondered why children used to pick and eat lead-based paint? Lead acetate is horribly bad for you, but tastes rather nice.


No presentation including Professor Sella would be complete without something exploding, and he didn’t disappoint by demonstrating the destructive power of flour dust, blowing the top off a can. He also answered the question, “Would baking in a vacuum make a cake rise more?” It turns out this is something he’s actually tried. The vacuum oven was written off as the splattered cake mix couldn’t be removed.

And finally a member of the audience turned out to be a food scientist who shared some videos of CAT scans of things baking, which turns out to be really useful for learning about how to control the air pockets that form as the cake rises. The cake samples weren’t half bad either.

Making The Body Invisible

The was the last presentation we attended, and I wasn’t sure how it was going to be as it sounded quite technical. I needn’t have worried though as Mark Lythgoe and team took us on a fascinating (and slightly shambolic) tour through a couple of cutting edge medical imaging techniques, in what was probably the most interesting talk we went to.

The first technology was about literally making tissue completely transparent (although only dead tissue). This requires two processes – removing the pigments, and injecting the tissue with a solution of the same refractive index so that light passes straight through. They demonstrated this live on stage with a tiny heart, lung and brain, and by the end of the talk it was finished and you could read writing placed underneath the organ, which was quite strange to see! (Obviously there was still some distortion, but that would have been caused by the irregular outer shape of the tissue).

The point of this is it gives an easier way to detect diseased tissue after a biopsy. Human tissue emits light, just like those glowy jellyfish, but very dimly. Different types of tissue give out different types of light, but because the body is opaque you can’t see it. By making the tissue invisible you can sense this light and spot diseased cells, which glow a different colour.

The second technology was photoacoustic imaging. When you fire a short pulse of bright light at something it heats up and expands. This expansion creates an ultrasonic sound wave, which is different depending on the material that is heated. The heating amount is very small (less than 1 degree), so it is safe to fire a laser pulse into the body to generate ultrasound from some distance underneath the skin. You can then use a detector and some clever maths to reconstruct a 3D image of the tissue structure that produced the sound.

Photoacoustic imaging is especially good at picking out melanin from surrounding cells, so by genetically engineering cells to produce melanin as well when another gene is active you can directly image gene expression. This has exciting implications for cancer research.

And More…

We also saw a hilarious set from the very talented Robin Ince, learned about the language of chimps with Liz Bonnin and friends, and heard some heated discussion about the heritability of intelligence between Robert Winston and Robert Plomin. But that’s enough words for one day. If you can, I highly recommend popping along to some talks next year!

Jun 132013

I hadn’t been to Cheltenham Science Festival before so last Friday I popped down for the day. I went to half a dozen presentations so here’s a summary of the interesting bits.

Eight Great Technologies

This was a talk by David Willetts, the Minister for Universities and Science, giving us reasons to be optimistic about the future of technologies, science and industry in the UK. Despite what the doom-mongers claim there are still loads of things that we’re good at in the country, and he talked about eight key areas where we shine:

  1. Computing and big data – we have excellent software engineers in many related industries (although I believe we need to do much more to encourage young people into programming), alongside smaller important projects such as the Raspberry Pi.
  2. Space and satellites – the UK is a world leader in making small satellites, and while we don’t have our own launch facilities, companies like Virgin Galactic are pushing further into the commercialisation of space.
  3. Robotics and autonomous systems – the new ESA Mars rover, Bruno, is developed using British technology, and will have much more autonomy than the existing rovers. Also interesting is the Symbrion robot ‘swarm’, developed in large part in this country.
  4. Synthetic biology – we have history in this area of developing gene sequencing and assembly technologies, and the existence of a unified NHS allows for more integrated ‘big data’ approaches to gene analysis and treatment evaluation.
  5. Regenerative medicine – from the original work on Dolly the sheep, we are now pioneering research into restoring lost body functions, for example the stem cell treatments for Jasper the paralysed dog.
  6. Agri-science – 80% of the world’s breeding chickens are designed in the UK, and now give twice as much meat per food as 20 years ago. Similar advances are being developed (and increasingly required) to increase wheat yields and reduce chemical use.
  7. Advanced materials and nanotechnology – from graphene to 3D printing, materials are a massive UK export industry (more about this in the next talk).
  8. Energy and storage – I think this is the most important technological legacy we should be funding and building on in the near future, so that we maintain our past expertise in nuclear and renewables.

Overall I was impressed by the Minister. I didn’t have any of the usual sense of frustration or brain-dissolving that I usually get when listening to politicians speaking, and despite not having a science background himself, he seems very able and keen to listen and learn. While it seems obvious to everyone in the field that many wide areas of science should get a lot more funding, I think that the focus on and support of key areas is probably a good compromise between results and political will. In particular, the derogatory remarks he kept making towards the Daily Mail and their ilk regarding their scare stories and general stupidity (my words but the general gist) reassured me that he has his head screwed on and that science in this country isn’t doomed yet.

A hare and a minotaur (I have no idea why)

Is The Age Of Silicon Over?

Next up was a talk on new materials, with three guys talking primarily about gallium nitride, graphene and metamaterials and photonics, respectively.

Gallium Nitride

Gallium nitride is a material with a wealth of possible applications. One common use at the moment is in LED lighting, where it is combined with indium to creates high brightness LEDs, and the wavelength of light (therefore the colour) can be controlled by the amount of indium used. Unfortunately, these GaN LEDs can only currently be fabricated on sapphire and are therefore very expensive to produce (hence LED bulbs costing £15 a pop). They are very efficient though, and have the potential to save 50% of the energy used in lighting, which makes up around 20% of the total UK energy use. New manufacturing techniques using silicon substrates instead of sapphire are being developed, and this should lead to a large reduction in cost and a much wider update of LED lighting.

Another really interesting use is that by combining it with aluminium instead of indium, you can produce LEDs that emit in the deep ultraviolet part of the spectrum. This type of light is fatal to life on earth, and the idea is that deep-UV lamps could be placed inside water pipes in developing countries where waterborne diseases are commonplace, killing all the microbes in the water at the point where it enters the home. A similar potential use is in air-con units to kill the recirculating bacteria.

A final use is that GaN is 40% more energy efficient that silicon when used for computing, thus leading to even more energy savings (another potential 5% off national consumption).


Graphene was in the news a few years back when Kostya Novoselov and Andre Geim at the University of Manchester won the Nobel prize for its discovery. Since then it’s all gone a bit quiet in the mainstream press but this ‘miracle material’ will likely still cause a revolution in many areas.

It is 100 times stronger than steel, harder than diamond, very conductive, 98% optically transparent and impermeable. The possible uses talked about were in flexible electronics (e.g. bendable screens), wearable computing and supercapacitors, where the tiny thickness enables huge surface areas to be contained in a small space. Another use is in very accurate sensors, but I didn’t really understand the specifics (seems to be to do with the change in Hall voltage when a single sheet of graphene comes into contact with even single atoms of the thing being measured).


Photonics is to do with processing and manipulating light. I have to admit I didn’t really take in anything that this guy was saying, save that optical computers are still a long way off and we’ll have to stick to electronic computers for the time being.

The festival venue

 Quantum Biology

With a title like this I couldn’t not attend, even though I didn’t really know what to expect. Executive summary: this is a very new field looking at quantum mechanical effects on and used by biological systems. And nobody is really sure how important it is.

The general principle is that classical physics works when you have loads of atoms or molecules, because all the quantum variations cancel out. However, down at the level of DNA and some cell biology you’re dealing with individual molecules, and therefore you may have to take quantum effects into consideration.

The problem with quantum biology is that to get observable quantum effects, you need coherence. For example, the double-slit experiment gives an interference pattern, showing photons behaving as waves, only when the you use a coherent light source such as a laser. In the warm and wet world of biology, being able to maintain coherence for long is challenging.

There are currently three main candidates for quantum effects – photosynthesis, sense of smell and magnetic sensing in birds. The most well-developed theory is with photosynthesis where it’s hypothesised that the electron transfer is made more efficient by quantum tunnelling – the tunnelling destinations are defined by the peaks in the interference pattern of a coherent source, similar to in the double-slit experiment.

There were some thoughts about consciousness being a result of quantum effects – the opinion being no, as thought is far too slow and the brain is too big and complex (all other observed quantum effects are between one or two molecules only).

One of the presenters, Paul Davies, finished up were some of his more ‘wacky’ (in his own words) theories. Did quantum mechanics facilitate life to begin with? Quantum superposition can enable rapid exploration of a vast number of arrangements of matter, and if a self-replicating state is in some way selected for, this could vastly reduce the search space. There is more about this in chapter one of his book.

Camera phones don’t work well in the dark

Particle Physics and Energy

These two talks weren’t presenting anything new, but were entertaining and fast-paced introductions to particle physics and the Standard Model, and the concepts of energy respectively. The Particle Physics talk went through 100 years of scientific progress, from the initial discovery of the atom to the Higgs boson, and our understanding of what all matter is composed of. The Energy presentation started with all the different forms energy can come in (kinetic, potential, sound, chemical etc) and how most of these are different forms of the same thing, before bringing in Einstein and the energy of empty space, and finishing with some brief words on the Casimir effect, negative energy and wormholes.

These were good fun but I think next time I’ll benefit more by heading to talks on subjects that I’m less familiar with, as they usually seem to pitched at a scientifically-literate but definitely non-expert audience.

I found the Portal facility

Famelab Grand Final

This session was well worthwhile. Famelab is an international competition to find the next generation of young science communicators. Contestants have three minutes to do a talk on an interesting scientific topic, but in as entertaining and engaging way as possible. All of the presentations were really good, and the winner was Fergus McAuliffe from Ireland, who you can see here talking about freezing frogs:

Another entertaining one was Christopher See from Hong Kong, talking about probabilistic medicine:

The rest of the talks are all up here as well.

Overall it was a very enjoyable and worthwhile day out, and I’ll definitely be going back next year.