NASA has disclosed the plans for a rocket successor to the space shuttle on Wednesday. This rocket would be the most powerful so far to take off from Earth. The design would cost $18 billion and is aimed at a 2017 unmanned test flight of the most powerful rocket since the moon race's Saturn V rockets.

It would push behind the moon, to asteroids and even to Mars and would serve as the backbone of the human spaceflight program.

The Space Launch System (SLS) will carry astronauts beyond earth's orbit by next decade, said Space agency chief Charles Bolden.

The rocket will take American astronauts further into space than ever before. Tomorrow's explorers will dream of one day walking on Mars, Bolden said, according to a report in USA Today.

We're investing in technologies to live and work in space, and it sets the stage for visiting asteroids and Mars, said Bolden at a news conference in Washington.

Given the federal budget constraint, the budget which is not finalized yet may be too steep.

SLS's first manned launch from Florida's Kennedy Space Center is scheduled for post-2021 and will cost several billion dollars per year more, thereafter.

The 2017 launch date is a hard deadline, regardless of ups and downs in NASA's budget, space agency official William Gerstenmaier said.

Unlike its previous program, Constellation, which has a very specific set goal - returning to the moon by 2020, NASA is yet to decide goals and destinations for the SLS.

We've talked conceptually about multiple destinations, Mr. Gerstenmaier said. We talk about an asteroid in 2025. We talk about Mars being the ultimate destination.

More details will be chalked out by next year. We can do pretty exciting missions with the capability that we've got, said Mr. Gerstenmaier,  according to New York Times.

NASA leaders also spoke about the boosted employment scope that the rocket would bring in to the states that are home to NASA centers, Florida, Alabama and Maryland.

In the case of a shortage of funds, the design work for the first manned launching which is scheduled for 2021 could be postponed further.

A launch, particularly aimed at an asteroid, could take place around 2025.

We do need a more crisp and clear answer for where NASA is going to go with the rocket, once they have it, said space policy expert John Logsdon of George Washington University in Washington, D.C. Given technological and budget realities, he said, pretty clearly, we aren't going to Mars in the next 18 years, said the report.