Ben Abbott: Earth Day at 50 has never been so relevant
FILE - This Dec. 24, 1968, file photo made available by NASA shows the Earth behind the surface of the moon during the Apollo 8 mission. (William Anders/NASA via AP, File)
FILE - This Dec. 24, 1968, file photo made available by NASA shows the Earth behind the surface of the moon during the Apollo 8 mission. (William Anders/NASA via AP, File)