NASA will celebrate the 40 anniversary of landing Americans on the moon in ceremonies July 20, the space agency announced.

On July 20, 1969, American astronaut Neil Armstrong made " … one giant leap for mankind" as he became the first human to step onto the surface of another celestial body.

It all was part of the Apollo Program, which saw repeated journeys to the moon in space capsules that looked somewhat similar to the next-generation U.S. spaceship, Orion, which will see its first manned flight in 2015.

A mockup of Orion will be on display today in front of the Smithsonian Institution National Air and Space Museum on the National Mall in Washington, D.C. (Please see story in this issue.)

NASA plans to use the Apollo anniversary to spur public interest in space, and to focus both on the history and the future of the largest space program on the planet.

Several items have been developed to aid the celebration, including an Apollo 40th anniversary logo, calendar of events and Web site.

The site NASA developed specifically for the Apollo 40th anniversary includes the special anniversary logo, an interactive feature about "moon trees" grown from seeds that flew on the Apollo 14 mission, and a "First Footprints" toolkit for use throughout the anniversary, which includes downloadable videos, images and events listings.

NASA’s official Apollo 40th anniversary Web site is located at: http://www.nasa.gov/apollo40th on the Web.

Before Orion flies on its first manned mission in 2015, however, NASA will face half a decade where it can’t get a single U.S. astronaut into space, even to low Earth orbit, because President Bush ordered the space shuttle fleet to stop flying next year. That will save money to develop Orion, Ares I and V, and the Altair lunar lander under the Constellation Program development effort. Not flying shuttles means the NASA budget doesn’t have to increase to develop the new spaceship system.

During that half decade gap, American astronauts will fly on Russian Soyuz spaceships.