Humanity must venture into space in search of new homes; if not, and if we destroy Earth, no one will be alive to carry on. People object that space flight wastes resources needed to help people on Earth, but even NASA spends only a fraction of 1% of the US’s gross domestic product. It’s both possible and necessary to fund improvements at home and exploration of space.

Going to the moon in 1969 advanced earthbound technology and inspired many to become scientists. After that project ended in 1972, interest and confidence in science waned: It hadn’t solved the social problems that plague us on Earth. A new initiative to put colonies on the moon and Mars would revitalize the public’s interest in science of all types.

Colonists could survive on the moon and elsewhere by digging underground, which would insulate them from temperature extremes and protect them from meteors, cosmic rays, and other space dangers. Mining would provide resources. From the moon, travel to other planets would be simplified. Mars would be next: As on the moon, water and oxygen could be obtained from the Martian ice caps, and minerals from vulcanism would be available through mining.

Some moons around Jupiter and Saturn may have life within oceans beneath the moon’s surfaces.