Lightning strikes may have supplied a key ingredient that allowed life to emerge on early Earth, according to a new study of "fossilized" lightning.

Advocacy groups are demanding the social network disclose how it reviews Spanish-language content and appoint a high-level executive to oversee policy and enforcement in Spanish.

The three-year deal came weeks after Facebook briefly blocked Australian news outlets' content on its platform to protest a change in the country's media law requiring the company to pay for it.

Researchers hope to learn about the effectiveness of the vaccine for kids ages 6 months to less than 12 years old. Moderna plans to enroll roughly 6,750 children in eight U.S. states and Canada.