Artist concept of NASA's new rocket, called the Space Launch System. Credit: NASA

Today NASA unveiled the design of a new rocket to help the agency meet a challenge from President Obama: send astronauts to an asteroid by 2025 and to Mars by the mid-2030s. Called the Space Launch System (SLS), the new heavy-lift launch vehicle will cost $18 billion, with its first test flight planned for 2017. It will be designed to carry the Orion Multi-Purpose Crew Vehicle for transport of crew and cargo.

The much anticipated announcement comes on the heels of the July retirement of the space shuttles, and is part of a plan laid out by the White House--the NASA Authorization Act of 2010--developed after Congress canceled a moon program, called Constellation, for the agency to focus on a vehicle to take astronauts to places like the moon and Mars while commercial companies focus on a rocket to transport crew to low Earth orbit.

The new rocket will include technology from the Space Shuttles and the Constellation program, which was building two rockets, Ares I and Ares V, and it will share a resemblance to the Saturn V, the first rocket to travel to the moon. "But it is difficult to compare rockets from one generation to the other" because of constant upgrades in technology and manufacturing techniques, said William Gerstenmaier, associate administrator for NASA's Human Exploration and Operations Mission Directorate, at today's press conference in Washington.

The SLS will use a liquid hydrogen and liquid oxygen propulsion system, which will allow NASA to reduce costs and leverage experience and existing technology, said NASA administrator Charles Bolden. The rocket will use five solid rocket boosters attached on either side of its core for the initial development flights, but NASA will hold a competition to replace these side-strapped boosters for more advanced designs. Gerstenmaier estimated the SLS thrust to be between 10 percent and 20 percent greater than that of the Saturn V.

Credit: NASA