CREDIT: NASA/Frankie Martin

NASA is currently preparing for Endeavour’s 25th and final flight as they continue to load her cargo bay with gear. Scheduled to take place on April 19th at 7:48 p.m., a 6 man crew will launch and then arrive at the station two days later. While they visit, four space walks have been scheduled before they return to earth on May 3 at 1:27 p.m.

This past week NASA moved Endeavour out of her maintenance hangar and positioned her in the Vehicle Assembly Building at Florida’s Kennedy Space Center. While Endeavour is prepped for her mission, Discovery is still in orbit. As Endeavour leaves, Discovery will be returning that same day.

“One mission is still going on, and Endeavour is getting ready for its next mission,” NASA spokesperson Allard Beutel told “It couldn’t be a more visible example of our busy space shuttle operations.”

Originally Discovery was supposed to land on March 8 and Endeavour was scheduled to launch the following day. Beutel said NASA officials will take the necessary time to determine whether to keep both events on the same day after Discovery’s flight was recently extended.

Endeavour’s mission is to deliver a $1.5 billion astrophysics experiment to the International Space Station. The instrument is called the Alpha Magnetic Spectrometer, and it is a huge detector designed to study cosmic rays and antimatter, and peer into the building blocks of the universe.

Afterward, Atlantis will be launched on June 28 to deliver spare parts and extra supplies.

The final launch of Endeavour is expected to draw quite a crowd. The fact that Discovery will be returning to while Endeavour is preparing to launch, “there’s obviously a lot more interest from the general public, and of course, the reporters who are covering the missions,” Beutel said.

The commander of Endeavour’s final flight will be veteran NASA astronaut Mark Kelly. Kelly is the husband of Arizona congresswoman Gabrielle Giffords, who is still recovering from a gunshot wound to the head that occurred in January during a tragic shooting spree in Tucson.

For more information, visit NASA’s mission page.