But, on the other hand, there was interplanetary travel here.

"But I'd like to try interplanetary travel just for the experience of it."

Why interplanetary travel should be thought of as a solution to all earth's problems I do not understand.

Interplanetary travel, however, appears to come with a price tag.

No, in the years before interplanetary travel, it was known as television.

The future of interplanetary travel seems mired in the past.

They didn't have the warp drive until then, so even interplanetary travel took them years.

The story takes place in the future, where trains are capable of interplanetary travel.

And, in response, we began to develop our own plans for interplanetary travel.

The trip to Mars had changed his perspective on interplanetary travel.