Vísindavaka 2026

As usual, members of the CMBeam team participated in the European Science Night. Here in Iceland this is called Vísindavaka. As before, our booth was equipped with our 2.4-m gravity demonstrator which is always a big hit. We find that the most effective demostration by far involves splitting the kids into two groups and then ask the groups to toss marbles into opposite directions. We subsequently get a lot of collissions and marbles falling into the center of the gravity well. The marbles that survive are typically all rotating in the same direction, just like the planets in our solar system :)

This time we also presented a 21-cm radio antenna based on a wok frying pan from IKEA! In theory, this antenna could be used to determine the rotation speed of the Galaxy through a Doppler-shifted emission lines from neutral hydrogen in the plane of our Galaxy. The idea is based on a famous paper posted on the arXiv a few years ago. A BSc student here at the Univeristy of Iceland was able to reproduce this experiment and successfully measure the rotation speed of the Galaxy. Miranda and I worked spend too much time perfecting the 3D printed mounting structure for the wok pan.