If you buy something using links in our stories, we may earn a commission. Learn more. Equations relating speed and mass go back to Newton and beyond. But after I got geeky with an equation for ...

In the week after Easter, we had a lot of old Peeps lying around. No one seemed that interested in eating them, so we used them to measure the speed of light. For centuries the speed of light was an ...

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in ...