NASA space shuttle Atlantis is set to liftoff on the final flight of the shuttle program, STS-135, a 12-day mission to the International Space Station. The launch is currently targeted for July 8 at 11:26 am EDT.

The space shuttle Atlantis will carry a crew of four: Commander Chris Ferguson, Pilot Doug Hurley, and Mission Specialists Sandy Magnus and Rex Walheim. Atlantis flew its maiden voyage on October 3, 1985, on the STS-51-J mission.

The shuttle will deliver the Raffaello multi-purpose logistics module filled with supplies and spare parts to sustain International Space Station operations once the shuttles are retired, during STS-135, which is the last planned space shuttle mission since STS-1.

The mission also will fly the Robotic Refueling Mission, an experiment designed to demonstrate and test the tools, technologies and techniques needed to robotically refuel satellites in space, even satellites not designed to be serviced.

The crew also will return an ammonia pump that recently failed on the station. NASA engineers want to understand why the pump failed and improve designs for future spacecraft.

NASA’s workhorses for the past 30 years have completed their mission to build and supply the orbiting outpost, and the agency is now looking to destinations beyond low-Earth orbit.

At NASA Kennedy Space Center's Launch Pad 39A, technicians have completed work to close out space shuttle Atlantis' aft section. Teams are not working any issues to prevent the start of the launch countdown at 1 pm EDT on July 5. Teams will have the Independence Day weekend off.

At NASA's Johnson Space Center, the STS-135 astronauts performed a final ascent simulation before the launch on July 8. The crew is set to arrive at Kennedy's Shuttle Landing Facility at about 2:45 pm on Monday.

Atlantis is centered over elements of the NASA emblem depicting how the space shuttle has been at the heart of NASA for the last 30 years. It also pays tribute to the entire NASA and contractor team that made possible all the incredible accomplishments of the space shuttle. Omega, the last letter in the Greek alphabet, recognizes this mission as the last flight of the Space Shuttle Program.

STS-135 will be the 33rd flight of Atlantis, the 37th shuttle mission to the space station, and the 135th and final mission of NASA's Space Shuttle Program.

NASA issued facts that 355 individuals will have flown 852 times on 135 shuttle missions, which includes the Atlantis' final mission, since STS-1 launched on April 12, 1981. The five orbiters have flown 537,114,016 miles. STS-135 will add more than 4 million miles to the total.

In addition, sixteen countries have been represented on shuttle missions: Belgium, Canada, France, Germany, Israel, Italy, Japan, Mexico, Netherlands, Russia, Saudi Arabia, Spain, Sweden, Switzerland, Ukraine and the United States.

The shuttles have docked to two space stations: Between 1994 and 1998, nine missions flew to the Russian Mir. With STS-135, 37 shuttle missions will have flown to the International Space Station. Additionally, for 77 times shuttles have landed at the Kennedy Space Center, 54 times at Edwards Air Force Base in California and once in the White Sands Test Facility, N.M.

Take a glimpse of space shuttle Atlantis and its crew:

Space Shuttle Atlantis to End NASA Program
On Launch Pad 39A at NASA's Kennedy Space Center in Florida, the access arm supporting the pad's White Room is in place against space shuttle Atlantis. NASA
Space Shuttle Atlantis to End NASA Program
Space shuttle Atlantis sits on launch pad 39A after rolling out from the Vehicle Assembly Building at the Kennedy Space Center in Cape Canaveral, Florida. Reuters
Space Shuttle Atlantis to End NASA Program
The sun rises over Launch Pad 39A and space shuttle Atlantis at NASA's Kennedy Space Center in Florida after completing its historic and final journey from the Vehicle Assembly Building. NASA
Space Shuttle Atlantis to End NASA Program
A banner proclaims the sentiments of Kennedy's work force at Launch Pad 39A at NASA's Kennedy Space Center in Florida, after space shuttle Atlantis completed its historic and final journey from the Vehicle Assembly Building. NASA
Space Shuttle Atlantis to End NASA Program
Space shuttle Atlantis sits on launch pad 39A after rolling out from the Vehicle Assembly Building at the Kennedy Space Center in Cape Canaveral, Florida. While unfavorable weather conditions may delay shuttle Atlantis' launch attempt on Friday as there is a chance for showers and thunderstorms in and around the Kennedy Space Center Friday morning. Reuters
Space Shuttle Atlantis to End NASA Program
Space shuttle Atlantis STS-135 (L to R) mission specialist Rex Walheim, mission specialist Sandra Magnus, pilot Douglas Hurley and commander Christopher Ferguson pose for a photo in the flame trench of launch pad 39A at the Kennedy Space Center in Cape Canaveral, Florida. Reuters
Space Shuttle Atlantis to End NASA Program
After completing simulated pad emergency exit training on Launch Pad 39A at NASA's Kennedy Space Center in Florida, the STS-135 crew members pause for a photo. From left are Commander Chris Ferguson, Pilot Doug Hurley, Mission Specialists Sandy Magnus and Rex Walheim. Mission Specialist Rex NASA
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