NASA confirmed on Monday that there will be no manned mission before March 2015, five years after the space shuttle is scheduled to retire. The agency also discussed budget plans, schedule and technical performance milestones for the Constellation Program.

The agency is planning on sending a new generation of explorers in space aboard the Orion crew exploitation vehicle, which is capable of carrying both crew and cargo. Also part of the Constellation Program are the Ares I and Ares V rockets, as well as the Altair lunar lander, which will be in charge of taking astronauts to the International Space Station after 2010, and send manned missions to the Moon.

Orion will be similar with Apollo spacecraft in terms of design, but it will be significantly larger: 5 meters in diameter, a mass of 22.7 metric tons, and over two-and-a-half times the volume of the Apollo capsule. The initial mission of Orion was to reach the International Space Station as early as 2014.

“Since the program’s inception, NASA has been working an aggressive plan to achieve flight capability before our March 2015 target,” Rick Gilbrech, associate administrator for the Exploration Systems Mission Directorate at NASA Headquarters in Washington, explained.

Gilbrech also added that they remain confident the Constellation Program will be ready to make its first flight to the ISS in March 2015 or prior to that date. “Our new path forward better aligns our project schedules with our existing funds to ensure we can address the unplanned challenges that always arise when developing a complex flight system.”

In other words, establishing 2015 as flight date doesn’t narrow down the possibilities, and NASA will continue to pursue its plans to send astronauts into space even prior to that. The purpose of the Constellation Program is to narrow the gap in America’s human spaceflight capability, NASA says.