Happy 50th Anniversary of Earth Day! Thinking today that most of you who are part of this challenge weren't even born in 1970. This is also the 50th year of the birth of the USEPA, the agency that issued the Clean Air and Clean Water Acts. I remember New York City before the Clean Air Act when catalytic converters weren't on our cars and a lot of garbage was incinerated with no filters on the stacks. Buildings were black and so was the inside of my nose after being exposed on the city streets! We owe a debt of gratitude to many scientists and policy makers who have gone before us and reclaimed much of the quality of our environment. There's more to do, but we have a better place to work from due to those who began this work long before us. Let's not let the current administration undo all that good work!