For this event, a group of researchers (in our case, 4 of us) get a spot on the museum floor to do some live demos and get people engaged with their research topic.
We were talking about magnetism, superconductivity and electricity generation. And, more importantly, how the research in the department is developing new materials that may be important in these areas in the future.
The use of liquid nitrogen turned out to be a big draw for the crowds, but I was impressed by the length of time people spent with us. They really wanted to hear more, not just see the "headline" demo and then carry on. We got some really interesting questions and comments from both children and their parents when discussing magnetism and superconductivity. My favourite comment was "It's not magic - it's science!" in relation to the floating magnet experiment shown below (explained here).