Dear EarthTalk:

Now that Earth Day is 50 years old, I’m wondering how it originally started and whether the Coronavirus put a damper on the celebration this year?

– Mary W.

Seattle, WA

Indeed, on April 22, Earth Day celebrated its 50th anniversary. Back in 1970, some 20 million Americans took to the streets, parks and auditoriums to demonstrate against pollution and other environmental ills stemming from 150 years of industrial development.

The idea for that first Earth Day sprung from Wisconsin Senator Gaylord Nelson, who was troubled by the environmental deterioration he witnesse...