Spotting Ice! (SPICE): infrared light-field tracking of icy particles

The overarching aim of our research is to study the structure and behaviour of the dusty and icy material that dominates the space environments where stars and planets form. In particular we are interested to understand how ice particles collide, stick, aggregate and grow, since these are the first stages of planet formation. The challenge is that our icy particles are often very small (about the same diameter as the width of a human hair), and moving very slowly (relatively speaking just a few centimetres per second - which if you were swimming at the same pace would mean it could take you 45 minutes or more to swim one length of a 25 m swimming pool!!). At this velocity particles are influenced by gravity on Earth, and that makes it difficult to collide them together, so typically we conduct these experiments in microgravity. To complicate matters further the type of ice that dominates in space is not like an ice cube from a fridge, but more like a fluffy sponge - it's amorphous ice.

So to be able to study such systems we combine constraints determined from observations from world-class telescopes with laboratory experiments, first conducted on Earth but then conducted on parabolic flights, or sub-orbital flights, to study icy grain aggregation. These experiments combine many techniques - but the dominant one is ultra-fast camera technology - much like the images you may have seen of slow-mo crash-test dummy images - we do the same - take multiple images (a video) of our particles colliding to work out what happens to them.

And although this studentship is motivated by a science research question, what we really need is increasingly more sophisticated camera technologies to elucidate the collision outcome processes. So-called light-field tracking, enables us to identify the exact positions (locations in space) and velocities of our particles during the experiments. But it turns out ice is not very easy to spot. So the aim of this proposal is to develop hyper-spectral infrared camera technology - where instead of looking for the icy grains with visible light, we will look at them at a variety of infrared wavelengths (up to 4 filters) where ice has spectral features specifically associated with water, and therefore be able to identify between icy and dusty grains, and potentially between amorphous and crystalline ices too.

The development of hyper spectral light-filed tracking camera technology will greatly benefit our research and enable us to study more complex systems and feed data back to the astronomy and space science community, but a hyper spectral light-field tracking IR camera has the potential to be a more widely applicable technology. Think of those areas like transport and food manufacture where ice play an important role.

This project is reliant on the unique partnership between the OU (academia) and DIAL Ltd, an SME with patents and expertise in camera technologies. Without this partnership the proposed technology development, and its testing in a research environment could not be realised, and not lead on to potential applications beyond astronomy.