We’re celebrating 180 years of Scientific American. Explore our legacy of discovery and look ahead to the future. Travel involves two main expenditures of energy: fighting gravity and propelling ...

NRA contribution data is from the 1998 through 2018 Congressional cycles and does not include individual expenditures or communication costs.

This article is brought to you by our exclusive subscriber partnership with our sister title USA Today, and has been written by our American colleagues. It does not necessarily reflect the view of The ...

Barbie Zelizer holds the Raymond Williams Chair of Communication at the University of Pennsylvania's Annenberg School for Communication. A former journalist, she focuses on the cultural dimensions of ...