For the first time in almost 40 years, NASA has completed all steps needed to clear a critical design review (CDR) for the most powerful rocket ever built that will take humans to deeper space missions, including Mars. The agency’s Space Launch System (SLS) is the first vehicle designed to meet the challenges of the journey to Mars and the first exploration class rocket since the Saturn V. SLS will launch America into a new era of exploration to destinations beyond Earth’s orbit.

This review is the last of four reviews that examine concepts and designs. The next step for the programme is design certification, which will take place in 2017 after manufacturing, integration and testing is complete. The design certification will compare the actual final product to the rocket’s design. The final review, the flight readiness review, will take place just prior to the 2018 flight readiness date.

The core stage of SLS, towering more than 200 feet tall and with a diameter of 27.6 feet, will carry cryogenic liquid hydrogen and liquid oxygen fuel for the rocket’s four RS-25 engines. SLS will be the world’s most capable rocket. In addition to opening new frontiers for explorers traveling aboard the Orion capsule, the SLS may also offer benefits for science missions that require its use and can’t be flown on commercial rockets. NASA recently completed the first developmental test series on the RS-25 engines.