A private space company announced Tuesday that it had landed a rocket upright and gently enough to be used again, a milestone in commercial aeronautics.

Reusing rockets, rather than discarding them, would be a big step toward making space flight less expensive.

The achievement produced "the rarest of beasts: a used rocket," Jeff Bezos, founder of the company Blue Origin, said in a statement. He is the CEO of Amazon.com Inc.

Blue Origin said the unmanned flight took place Monday morning at its site in Van Horn in West Texas. The secretive company, based in Kent, Wash., did not invite reporters to attend.

- AP