Doug Cooke is an aerospace consultant with over 49 years in NASA programs. James Green is the chief executive officer at Space Science Endeavors LLC and former NASA chief scientist.
The United States has created a major leap forward in space leadership with the inaugural flight of the Space Launch System (SLS) carrying Artemis 1 to the Moon. Although the development of the SLS was driven by launch needs for human exploration of the Moon and Mars, it provides a much greater level of capability for the broader spacefaring community. Numerous human exploration architectures for going to the Moon and then onto Mars have defined the scale of operations, mission requirements, and the necessary mission infrastructure for which the SLS was designed to accomplish.
The NASA exploration architecture, which includes the Artemis Base Camp, complete with hardware concepts, drives out flight element mass and volume requirements that are not compatible with existing Earth Orbit launch vehicles. This is where the super heavy-lift SLS launch vehicle designed to accommodate large integrated flight elements — landers, human habitat modules, pressurized rovers, etc., reduces design complexity and mission risk. Without the SLS, breaking designs down to fit into smaller launch vehicles, creates the need for complex and heavy docking or berthing interfaces to join the components and necessitates more launches and complex assembly operations in space. Reliability, probability of mission success, and crew safety benefit greatly from reduced complexity.
The SLS is now a proven system based on heritage propulsion capabilities of the Space Shuttle solid rocket boosters, and main engines. These designs were evolved over the life of the shuttle program and enhanced with the latest technologies for the Artemis Program.
While the SLS design was driven by human exploration requirements, the mass and volume capacity offer enormous benefits for space mission objectives from NASA science disciplines and other commercial customers. As described briefly above, SLS’s capability can be used for large heavy payloads, or multiple payloads to different destinations, very large foldable telescopes, or carry the additional stages to boost payloads at much higher velocities so necessary to leave the solar system and better explore the region between the stars within a researcher’s lifetime.
Science missions to the outer planets of the solar system and beyond can benefit from the increased mass for more capable missions and/or increased velocity to reduce mission duration to a more acceptable time. The larger volume and diameter for payloads can reduce spacecraft complexity and enable larger apertures for telescopes. Some missions are not even practical or possible without the enormous capabilities in speed and ultra-heavy lift capabilities of the SLS such as the Interstellar Probe currently being considered through the National Academy’s Heliophysics Decadal process.
Similarly, the SLS will provide a unique new capability for other government and international exploration missions with a scale not available since the Apollo Saturn V. It has taken the United States some 50 years to re-establish this level of launch capability through years where budgets have been constrained and in competition with other priorities. Now we are at the point of using the SLS by beginning exploration missions to the Moon than Mars. It is important to leverage the investment in this unequaled capability and continue to accelerate U. S. leadership in space by executing the more challenging and capable human and robotic missions that this nation is known for accomplishing.