In technological terms, space voyages and environmental protections seem different in character, with the former being intense, high speed, and adventurous, with connotations of state-of-the-art technology, while the latter is a gentle green public-service activity, one which, though involving technology, doesn’t give the impression of being as difficult as the former.
But that is only an impression. The true situation is: If we want to achieve the present targets for environmental protection, the technology needed is more difficult to develop than that for large-scale interplanetary travel.

What It Means

This is a placeholder explanation generated by the low-overhead model. It interprets "In technological terms, space voyages and environmental protections seem different in character, with the former being intense, high speed, and adventurous, with connotations of state-of-the-art technology, while the latter is a gentle green public-service activity, one which, though involving technology, doesn’t give the impression of being as difficult as the former.
But that is only an impression. The true situation is: If we want to achieve the present targets for environmental protection, the technology needed is more difficult to develop than that for large-scale interplanetary travel." in the context of "One and One Hundred Thousand Earths (pp. 73-74)" to mean that wisdom is timeless.