In a related vein, the kid who built a fusion reactor in his bedroom--which was on the HN front page the other day--had a fascinating comment about visualizing

In a related vein, the kid who built a fusion reactor in his bedroom--which was on the HN front page the other day--had a fascinating comment about visualizing a single neutron: Q: How does one detect fast neutrons? A: Neutron bubble dosimeter. It is basically a tube full of gel suspending small drops of a special liquid. If a fast neutron strikes one of these droplets, the drop vaporizes and turns into a visible bubble. It still amazes me that a single neutron has enough energy to make its presence known to my naked eye.[1] [1] https://www.reddit.com/r/IAmA/comments/4tgsaz/iama_i_built_a_fusion_reactor_in_my_bedroom_ama/d5hbr6r https://www.reddit.com/r/IAmA/comments/4tgsaz/iama_i_built_a...