This is an unflown personnel parachute from the Gemini human spaceflight program. These parachutes would be used by the astronauts after leaving the capsule in an emergency during launch or the latter stages of reentry. Manufactured by Northrop Ventura, it is made of nylon and is 28 feet in diameter when fully deployed. The parachute was located at the right rear of the pilot's backboard. It was deployed by the drogue mortar slug and pilot chute.
In 1971, McDonnell Douglas Astronautics Company in St. Louis transferred many leftover artifacts from the Gemini program to the Smithsonian on behalf of the National Aeronautics and Space Administration, including this parachute. The former McDonnell Aircraft Corporation had manufactured the Gemini spacecraft.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.