You can view sunspots with just a cardboard box! https://www.nationalgeographic.org/activity/build-a-sunspot-viewer/ https://www.nationalgeographic.org/activit

You can view sunspots with just a cardboard box! https://www.nationalgeographic.org/activity/build-a-sunspot-viewer/ https://www.nationalgeographic.org/activity/build-a-sunspot-...