Japanese scientists successfully tested a 'space cannon' this week

Not content with merely breaking the bonds of gravity and touching the face of God, now we want to fire plastic explosive into it.

A reminder there are some damned exciting space plans being worked on right now - in Japan, scientists report that a “space cannon” they have been building is armed and fully operational, and has been tested successfully (albeit not actually yet in space).

Hayabusa-2, designed and built by the Japan Aerospace Exploration Agency (JAXA for short) will be launched into space next year, and head off to intercept the orbit of an asteroid called 1999JU3. It’s the successor probe to Hayabusa-1, which landed on the asteroid Itokawa in 2005, collected some samples, and returned home. It was the first such sample-and-return mission, one which Hayabusa-2 will build on.

1999JU3 is roughly a kilometre in diameter, and is an Apollo asteroid. That’s a class of asteroid that orbits the Sun within the orbit of Mars, in between the innermost three plants of Mercury, Venus and Earth. They occasionally cross into our orbit, making them a threat - that’s what the Chelyabinsk meteor was - but 1999JU3 isn’t. It is an interesting one, though, because it’s assumed to be made up of material similar to those found on the early Earth, and thus carry some of the organic compounds that we assume, on our planet, become life.

But you’re here for the space cannon, right? Here’s how it’s going to work.

After arriving at the asteroid sometime in 2018, and after taking 18 months’ worth of readings, Hayabusa-2 will deploy its cannon on one side of the asteroid (plus a camera so it can watch) before heading over to the opposite side. That way, nothing from the explosion should damage it.

Then, the space cannon will drift in. As it gets close to the surface it’ll detonate, firing a bullet containing 4.5kg of plastic explosive into the asteroid’s surface, blowing a crater into the asteroid’s side. Hayabusa-2 will emerge from hiding on the far side, swoop down to the exposed wound, and scoop up some samples. Then it’ll fly home, returning by 2020.

Alas, it is not quite as cool as Nasa’s awesome plan to capture an asteroid and pull it into orbit around the Moon. If we did that, we could send astronauts to it as practice for tricky things like landing on Mars or even distant moons. We might be watching footage of humans setting foot on another tiny alien world as soon as 2021, as long as funding can be found.
 

Artist's Concept of Hayabusa-2. (Image: Akihiro Ikeshita/JAXA)

Ian Steadman is a staff science and technology writer at the New Statesman. He is on Twitter as @iansteadman.

Yu Ji/University of Cambridge NanoPhotonics
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Nanoengine evolution: researchers have built the world’s smallest machine

The engine could form the basis of futuristic tiny robots with real-world applications.

Richard P Feynman, winner of the Nobel Prize in Physics in 1965, once remarked in a now-seminal lecture that a time would come where we would “swallow the doctor”. What he meant, of course, was the actualisation of a science-fiction dream – not one in which a universal cure-all prescriptive drug would be available, but one in which society would flourish through the uses of tiny devices, or more specifically, nanotechnology. 

First, a quick primer on the field is necessary. Nanoscience involves the study and application of technologies at an extremely tiny scale. How tiny, you ask? Given that one nanometre is a billionth of a metre, the scale of work taking place in the field is atomic in nature, far beyond the observational powers of the naked human eye.

Techno-optimists have long promoted potential uses of nano-sized objects, promising increases in efficiency and capabilities of processes across the board as a result. The quintessential “swallow the doctor” example is one which suggests that the fully-realised potential of nanotechnology could be applied to medicine. The idea is that nanobots could circulate our bodily systems in order to reverse-engineer the vast array of health problems that threaten us.

It’s natural to be sceptical of such wild aspirations from a relatively young field of study (nanoscience unofficially began in 1959 following Feynman’s lecture “There’s Plenty of Room at the Bottom”), but associated research seems to be gaining widespread endorsement among prominent scientists and enthusiasts. Ray Kurzweil, Director of Engineering at Google, thinks a booming nanotechnology industry is crucial in the creation of a technological singularity, while futurist and viral video philosopher Jason Silva believes the technology will help us cure ageing.

The high-profile intrigue surrounding nanotechnology means that word of any significant developments is certain to stimulate heightened interest – which is why researchers’ achievement in building the world’s tiniest engine this month is so significant.

Reporting their results in the journal Proceedings of the National Academy of Sciences, the University of Cambridge researchers explained how the nanoengine was formed and why it represented a key step forward in the transition of the technology from theory to practice.

The prototype nanoengine is essentially composed of charged particles of gold, bound by polymers responsive to temperature in the form of a gel. The engine is then exposed to a laser which beams and heats the device, causing it to expel all water from the polymeric gel. The consequence of this is a collapsing of the gold particles into an amalgamated, tightened cluster. Following a period of cooling, the polymer then begins to reabsorb the water molecules it lost in the heating process, resulting in a spring-like expansion that pushes apart the gold particles from their clustered state.

"It's like an explosion," said Dr Tao Ding from Cambridge's Cavendish Laboratory. "We have hundreds of gold balls flying apart in a millionth of a second when water molecules inflate the polymers around them."

The process involved takes advantage of the phenomenon of Van der Waals forces – the attraction between atoms and molecules. The energy from these forces is converted into elastic energy, which in turn is rapidly released from the polymer. "The whole process is like a nano-spring," said Professor Jeremy Baumberg, who led the research.

Scientists have been tirelessly working towards the creation of a functional nanomachine – one which can effortlessly swim through water, gauge its surroundings and communicate. Prior to the research, there was a difficulty in generating powerful forces at a nanometre scale. These newly devised engines, however, generate forces far larger than any previously produced.

They have been named “ANTs”, or actuating nano-transducers. "Like real ants, they produce large forces for their weight. The challenge we now face is how to control that force for nano-machinery applications," said Baumberg.

In an email exchange with New Statesman about the short-term and long-term goals in bringing this engine closer to a practical reality, Baumberg said: “It allows us for the first time, the prospect of making nano-machines and nanobots. The earliest stage applications we can see are to make pumps and valves in microfluidic systems. Microfluidic chips are really interesting for synthesising pharmaceuticals, biomedical sensing and separation, as well as many other biochemical processes.

“But all pumps and valves currently need to be made with hydraulics, so you need a pipe onto the chip for each one, limiting strongly the complexity of anything you do with them. We believe we can now make pumps and valves from the ANTs which are each controlled by a beam of light, and we can have thousands on a single chip. Beyond this, we are looking at making tiny nanomachines that can walk around, controlled by beams of light.”

The embedding of nanobots into all facets of culture is still a long way off, and researchers will need to find a way of harnessing the energy of nanoengines. However, the prospect of one day seeing the fruition of nanorobotics is worth all the patience you can get. The tiniest robot revolution has just begun.