Saturday is Earth Day, the annual holiday to advocate good stewardship of the planet, launched in 1970 by the late Wisconsin senator Gaylord Nelson. This year it will be marked by a March for Science, which bills itself as a “global movement to defend the vital role science plays in our health, safety, economies and governments.” We have mixed feeling about the pairing. Science, to be credible, must be impartial, objective and nonpartisan. The widespread reduction of federal support for scientific endeavors proposed by the Donald Trump administration – cuts to budgets of the National Institutes of Health, the EPA, NASA and agencies performing and funding research – would do great harm. They would slow the quest to cure disease, feed a hungry world, combat climate change and keep the U.S. economically competitive. That makes the need to rally public support of the scientific research imperative. Marches by scientists and their supporters, however, risk being seen as political acts. If so, that could hurt support for science in the long run. Countering that is the potential for demonstrating that scientists are not rarified beings who all look like Dr. Emmett Brown in Back…