NASA to unveil heavy-lift rocket

— -- NASA will raise the curtain Wednesday on the long-awaited design of a super-sized rocket that will propel U.S. astronauts to an asteroid by 2025 and then missions to Mars in the following decade, senior Obama administration officials told Florida Today.

More than 30 stories tall, the Space Launch System will be the most powerful American rocket since the Saturn V that thundered aloft with Apollo astronauts destined for moon landings in the late 1960s and early 1970s.

NASA's Orion crew capsule is designed to ride atop it.

An initial unmanned test flight is slated for 2017. A first piloted shakedown cruise would follow in 2021.

U.S. astronauts then would make preparatory voyages about once a year before setting sail on an expedition to an asteroid in 2025.

Senior administration officials say the heavy-lift development program will cost $3 billion per year. That's about the same amount that NASA spent to run the space shuttle program in 2009.

"We are trying to make this as affordable and sustainable as possible," an administration official said. "That's a large part of what we've been doing over the last year."

NASA Administrator Charles Bolden will detail the plan in a morning news conference on Capitol Hill with U.S. Sens. Bill Nelson, D-Fl., and Kay Bailey Hutchison, R-Texas, two big backers of the project.

The heavy-lift rocket, which will launch from Kennedy Space Center, will be about 34 stories tall. Its development will leverage billions of dollars of investments already made in the shuttle program and the cancelled Project Constellation return-to-the-moon initiative.

The major components of the rocket:

• The vehicle's core stage will be a stretched version of the shuttle's bullet-shaped external tank. It will be powered at first by five space shuttle main engines; an upgraded version of the engine will be developed for use later on.

• The second stage of the rocket will be powered by a J2X engine, which already is in development. An advanced version of a Saturn V second-stage engine, the J2X would have been the second stage of Project Constellation's Ares I and Ares V rockets.

•The vehicle also will be equipped with either shuttle-derived solid rocket boosters or liquid-fueled boosters.

There will be a booster contract competition that will be based on cost and performance requirements. Administration officials envision potential cost savings and improved performance.

"We thought we could get both cost and performance savings by doing the competition," a senor administration official said.

The Obama White House considers the heavy-lift rocket and Orion crew capsule programs crucial parts of an affordable program that calls for:

• Extending International Space Station operations to at least 2020.

• Investing in the development of commercial spacecraft to ferry astronauts to and from the International Space Station and other low Earth orbit destinations.

"It really is critical that we pair this with the commercial crew program. That is the way that NASA is going to have sustainable resources in the long run to be able to focus on deep space," a senior administration official said.

"And so we really see this all as being linked. Commercial crew will be our transportation to and from the International Space Station and low Earth orbit, and then to go farther, we really need to focus on building the larger rocket and (Orion) crew vehicle."