That’s exactly where two astrophysicists from the National Schools Observatory at John Moores University, Liverpool have found themselves. They’ve taken on a very important public engagement mission – explaining the mysteries of Dark Matter – and have chosen to reach a very different audience by participating in the Chelsea show. The RHS Chelsea Flower Show is enormous, with 161,000 taking in the gardens in person and many more watching the television coverage – it’s a truly international event.
Surprisingly, Professors Andy Newsam and Mike Bode have some experience in these matters. In 2013 they, together with designer Howard Miller and a landscaping team, put together a garden for the RHS Tatton garden show. Their garden, ‘The Galaxy’, represented a spiral galaxy, complete with a ‘black hole’ in the centre! With 10,000 show visitors walking through the garden, and queues forming to chat to the scientists, they really managed to capture the public’s imagination, and get them fired up about science.
The design of the Chelsea garden has to deal with a significant problem – how do you represent something that you can’t see? Dark Matter is believed to make up the bulk of the ‘stuff’ in the Universe, but it defies direct detection, and we just can’t see it. We have plenty of indirect evidence that it must be there, and scientists are looking for Dark Matter in a variety of different ways.
The Dark Matter garden shows that we can be affected by things that we can’t see by using wind as a metaphor – a lot of the planting involves grasses that sway, being affected by the invisible force of the wind.
Light, which you might expect to travel in straight lines, is bent by gravity – a phenomenon called gravitational lensing. Gravitational lensing is one of the ways that we can indirectly ‘see’ dark matter, when light from distant galaxies is bent more than we would expect if the only matter in its path is the stuff we can see. To illustrate this, the Dark Matter design uses bent metal poles to track the path of light across the garden. The result is viewed through an oculus at the front of the garden.
The Dark Matter garden has been designed to capture the imagination, to reach a new audience and to explain the wonders of science. To see images of the finished garden, and some of the media coverage and public responses, click through to our Dark Matter garden Storify.