NASA is planning to conduct in spring 2009 the first test flight of a new carrier rocket with an advanced launch vehicle to replace the outdated space shuttle, the U.S. space agency said in a statement.

"NASA is developing new spacecraft, the Ares rockets and Orion crew capsule, to deliver astronauts to the International Space Station (ISS) and send them on their way to the Moon," the statement said.

The prototype rocket, known as Ares I-X, is scheduled for launch in spring 2009 before the "retirement" of the space shuttle fleet in 2010.

"The Ares I-X flight will provide NASA an early opportunity to test and prove hardware, facilities and ground operations associated with the Ares I crew launch vehicle," the agency said on its website.

NASA is planning to complete the testing of the Aries I by 2013 and send astronauts on board the new launch vehicle to the ISS in 2015. Until then crew rotation and cargo delivery missions to the ISS will be tentatively carried out by Russian Soyuz spacecraft and Progress space freighters.

Russia currently charges around $50 million for each American astronaut delivered to the orbital station.

The reusable Aries I rocket is part of the ambitious Constellation program developed by NASA to maintain a U.S. presence in low Earth orbit, to return to the Moon and establish a base there, and to lay the foundation to explore Mars and beyond in the first half of the 21st century.

A new generation of spacecraft for human spaceflight under the Constellation program consists primarily of the Ares I and Ares V carrier rockets, the Orion crew capsule, the Earth Departure Stage and the Altair lunar lander.

NASA earlier said U.S. astronauts could be back on the Moon by 2020.