Adjust the colors to reduce glare and give your eyes a break. Use one of the services below to sign in to PBS: You've just tried to add this video to My List. But first, we need you to sign in to PBS ...

When acidic materials are spilled, the clean-up procedure involves adding a base chemical to neutralize the acid. Up to a point, the more base added, the more neutral and less toxic the spill becomes.

It’s hard to imagine a more inhospitable world than our closest planetary neighbor. With an atmosphere thick with carbon dioxide, and a surface hot enough to melt lead, Venus is a scorched and ...