By: Martin Burkey
As anticipation builds for the forthcoming crewed missions of the Artemis program, NASA is engaged in the active development of an advanced version of its SLS (Space Launch System) rocket, earmarked as Block 1B. This heightened variant is anticipated to dramatically increase the launch vehicle’s payload capacity, enabling it to concurrently transport astronauts and substantial lunar equipment in a singular mission. This upgrade is scheduled to make its maiden voyage on the Artemis IV mission.
“The SLS was intentionally engineered from the outset to adapt and support heightened performance configurations, thus providing a versatile platform for expanding our exploration of the solar system,” stated John Honeycutt, the SLS Program manager. “The refinements in store for the SLS’s engines, boosters, and the upper tier stem from the proven Block 1 design which was initially employed during the Artemis I launch in November 2022 and will be reused for the inaugural crewed missions of Artemis II and III.”
Manufacturing operations for the rocket’s new configurations have commenced at NASA’s Michoud Assembly Facility situated in New Orleans, and preparations for a series of rigorous green run tests for the enhanced upper stage are set to occur at Stennis Space Center in Bay St. Louis, Mississippi.
The Block 1B maintains the fundamental design elements of its precursor – the core stage, solid rocket boosters, and associated components. However, it boasts two major enhancements: a potent second stage and a universal cargo adapter. These advancements are set to significantly boost the operational capabilities of NASA’s primary lunar exploration rocket for future missions.
James Burnum, deputy manager of NASA’s Block 1B Development Office, explained, “The SLS Block 1B is poised to become the principal vehicular mode for lunar astronaut transportation. By leveraging the design, tests, and flight history of the SLS Block 1, we aim to construct a robust and safe transportation system capable of launching larger and heavier lunar payloads in a single expedition.”
The current interim cryogenic propulsion stage (ICPS), equipped with a single engine for the initial three Artemis missions, is slated to be succeeded by the exploration upper stage (EUS), sporting four engines. The EUS is expected to support mission needs for the first eight hours post-launch – a significant increase from the ICPS’s two-hour capacity. This change necessitates the introduction of new hardware and software specifically designed and tested to withstand the altered performance and environmental dynamics.
An additional change involves the universal stage adapter, which not only physically links the rocket to the Orion spacecraft but also provides ample cargo space (over 10,000 cubic feet or 286 cubic meters) for transporting large components, such as parts of NASA’s prospective Gateway lunar orbit outpost as well as facilitating unique scientific endeavors.
These modifications promise to augment the SLS’s payload capacity from 59,000 pounds (27 metric tons) to approximately 84,000 pounds (38 metric tons). The four RL10 engines, earmarked for the EUS green run test series at Stennis, have been completed, and the core stage productions for Artemis IV are advancing.
Substantial improvements in the SLS design also mean more frequent launch windows for missions to the Moon, with the EUS offering double the number of daily launch opportunities in comparison to its predecessor, the Block 1. This is made possible by quadrupling both the engines and the propellant capacity, thus increasing thrust.
Another benefit includes enhanced communication channels between astronauts and the ground teams with the in-space stage, alongside the ability to utilize Orion’s docking system for extracting payloads intended for the Gateway from the stage adapter.
With ambitions to have the first woman, the first person of color, and an astronaut from an international partner land on the Moon, NASA is actively working towards these milestones with the Artemis program. The SLS stands as a core element of NASA’s deep space exploration initiatives, which also encompass the Orion craft, the Moon-orbiting Gateway, commercial lunar landing systems, advanced spacesuits, and surface rovers. The SLS is unequivocally the only rocket capable of dispatching the Orion, its astronaut crew, and essential cargo to the Moon in one launch.
Corinne Beckinger
Marshall Space Flight Center, Huntsville, Ala.
256.544.0034
corinne.m.beckinger@nasa.gov
FAQ Section
What is the Block 1B version of SLS?
Block 1B is an upgraded version of NASA’s Space Launch System rocket, designed to carry a larger payload and provide more powerful thrust compared to its predecessor, Block 1.
When is the Block 1B expected to debut?
The Block 1B is expected to debut for the Artemis IV mission.
What are the major changes in the Block 1B design?
Block 1B will feature a more powerful second stage known as the exploration upper stage (EUS) with four engines and a universal stage adapter for carrying larger payloads, including components for the Gateway lunar outpost.
How much more payload can Block 1B carry compared to Block 1?
Block 1B can carry approximately 84,000 pounds (38 metric tons), while Block 1 can carry 59,000 pounds (27 metric tons).
How does the EUS improve launch opportunities for lunar missions?
The EUS, with four times the engines and almost four times the propellant and thrust compared to the ICPS, enables two daily launch opportunities, enhancing mission flexibility.
Conclusion
The evolution of NASA’s Space Launch System into Block 1B marks a significant milestone in lunar exploration capabilities. By incorporating key enhancements such as a more powerful upper stage, increased payload capacity, and improved flexibility in launch scheduling, NASA aims to achieve a new era of deep space missions. The impending Artemis IV mission showcases the potential to further explore the moon, enabling unprecedented scientific discovery and continuing humanity’s quest for knowledge beyond our own planet.