Astronauts Mark Space Anniversaries As Shuttle Retirement Looms

The 13 astronauts aboard the linked shuttle Discovery and space station marked the twin anniversaries of the birth of human spaceflight and NASA?s space shuttle fleet Monday, even as the U.S. space agency is winding down its reusable space plane program.

Discovery has been docked at the space station since last week as its crew hauls tons of cargo into the station. The first-ever shuttle mission, STS-1 aboard Columbia, launched 29 years ago today, exactly two decades after the former Soviet Union inaugurated the era of human spaceflight with the launch of cosmonaut Yuri Gagarin into orbit in 1961.

Now, NASA plans to launch just three more shuttle flights after this one before retiring the three-orbiter fleet in September. To date, 131 shuttle missions ? including Discovery's ? have launched into space.

"I think everyone feels a little bittersweet about seeing the space shuttle come to an end," Discovery's pilot Jim Dutton told reporters today in a series of televised interviews. "We really have a lot of people who love the shuttle, but we have to continue to press into the future."

NASA's future, currently, calls for the cancellation of the Constellation program that was building the new rockets and spaceships to replace the retiring shuttle fleet. Instead, the space agency plans to rely on Russian Soyuz spacecraft to send astronauts to the International Space Station until U.S. commercial spacecraft are available to ferry crews to and from low-Earth orbit.

U.S. President Barack Obama announced the new direction for NASA in February. He is expected to announce new details on Thursday during a presidential visit to the Florida home of NASA's space shuttle fleet.

"I'm hopeful for the future, and I think the leadership and the folks who make policy decisions will do the right thing and we'll be able to get the job done," said Discovery commander Alan Poindexter.

There have been two shuttle accidents in NASA history.

The January 1986 Challenger shuttle disaster occurred just after liftoff, when the spacecraft exploded and broke apart. The shuttle Columbia broke apart during re-entry on Feb. 1, 2003 due to heat shield damage. In all, 14 astronauts were killed. After each accident, NASA stood down from shuttle flight for two years to make safety changes.

Space shuttle firsts

Nearly 30 years after the first shuttle flight, there is still room for space firsts.

This mission joined four women in space (three on Discovery and one on the space station) for the first time. One of those female spaceflyers ? Japanese astronaut Naoko Yamazaki ? also joined fellow astronaut Soichi Noguchi of Japan at the station when the shuttle arrived ? the most Japanese astronauts ever in space at one time.

Yamazaki and Noguchi spoke with Japanese space officials and schoolchildren early Monday. They even paused to recite haiku, Japanese poems, and play a traditional Japanese folk song on a wooden flute and stringed instrument.

For Discovery astronaut Dorothy ?Dottie? Metcalf-Lindenburger, 34, the mission is especially poignant. As a young girl, Metcalf-Lindenburger attended Space Camp in Hunstville, Ala. She remembers when her mother bought her a model space shuttle. The name on that toy shuttle: Discovery.

"I think it's pretty special that I got to come up on Discovery," Metcalf-Lindenburger said.

Discovery is the oldest of NASA's three-orbiter fleet, but wasn't the first shuttle to fly. NASA launched STS-1 with a skeleton crew of two test pilots aboard ? veteran Apollo and Gemini program astronaut John Young and then-rookie Robert Crippen. The two men were in space for about two days after launch on April 12, 1981.

Space shuttle lasts

With just three more planned shuttle missions after this one, Discovery's flight is also marked by some lasts. Metcalf-Lindenburger is the last of NASA's teacher-astronauts expected to fly on a U.S. space shuttle.

The mission is also the last shuttle flight expected to carry a Japanese crewmember and the final mission to include a full seven-person crew ? making the 13 astronauts aboard the station the last big crowd in orbit. Each of the remaining three shuttle missions will have six-person crews, NASA officials have said.

Discovery launched toward the space station on April 5 and is due to land on April 19. The seven astronauts took a half-day off today, moved some of the 17,000 pounds (7,711 kg) of cargo they are delivering into the space station and also prepared for their mission's third and final spacewalk.

That final spacewalk is set to begin early Tuesday morning.

Dutton said that while NASA's space shuttles are old, they are nonetheless marvels of human engineering.

Without the shuttle fleet, iconic spacecraft like the Hubble Space Telescope wouldn't have experienced the success that they have. The shuttle's ability to carry astronauts to Hubble and fix it over time has been a huge factor in the space observatory's success.

The shuttle also has a huge, 60-foot (18-meter) payload bay, making it the only spacecraft in service today capable of hauling large pieces and spare parts to the space station.

The $100 billion space station has been under construction since 1998. NASA's last few shuttle flights have been dedicated to stocking up the space station with the parts it will need to keep flying through at least 2020.

"It's been a tremendous vehicle," Dutton said, with the space station serving as the "crown jewel" of the space shuttle era. "We're going to miss it. There's no question about it."

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