A flat desert grassland in southeastern Arizona is being considered as a potential landing site for a new reusable spacecraft.
Other possible landing sites include White Sands Missile Range in New Mexico, Dugway Proving Ground in Utah and Edwards Air Force Base in California.
About 65 miles east of Tucson, Willcox Playa is winter habitat for thousands of migratory sandhill cranes.
The Starliner capsule made a safety test flight Monday at White Sands.
The capsule is due for a test flight next month to the International Space Station with a dummy and some cargo on board.