SLS: Pioneering the Future of Space Exploration & Scientific Discovery

The SLS builds upon the Saturn V legacy, paving the way for exciting lunar and deep space missions.

April 08, 2025 in Space

The Exploration Upper Stage (EUS) by the lunar surface, with Mars in the background.

As we enter a new era of space exploration, the Space Launch System (SLS) rocket symbolizes humanity's enduring quest to explore the unknown. It is the only proven, super heavy-lift rocket capable of carrying both crew and cargo to lunar orbit in a single launch.

Boeing’s history supporting deep space initiatives dates back to the Apollo era, during which it, along with its heritage companies, built every element of the Saturn V rocket. This single-use vehicle was a marvel of its time. Today, Boeing continues to build upon this legacy through the design, development, test and manufacturing of the core stage, upper stage and avionics suite for the SLS fleet.

To fully utilize the capabilities of this new rocket, it’s imperative to leverage historical achievements while ensuring the potential of the SLS rocket, along with its EUS capabilities, is maximized for future missions.

The Saturn V Legacy

The Saturn V rocket was a groundbreaking achievement in aerospace engineering, serving as the backbone of NASA's Apollo program, which successfully landed humans on the Moon between 1969 and 1972. Standing 363 feet tall, the Saturn V could deliver 140 metric tons to low Earth orbit. Its three-stage design utilized powerful F-1 engines that generated an impressive 7.5 million pounds of thrust at liftoff, making it the most powerful rocket ever built.

The Saturn V rocket is renowned not only for its engineering achievements but also for the missions it enables. The Apollo program, including the historic Apollo 11 mission, showcased human ingenuity and provided invaluable scientific data about the Moon.

Following Apollo, missions like the Viking landers and Voyager spacecraft further advanced our understanding of Mars and the outer planets. These missions provided critical insights into atmospheres, geology, and potential for life; present-day science missions largely center on expanding the foundational knowledge that was gathered during the Apollo era.

The legacy of these missions highlights the need for ongoing investment in science and exploration. NASA’s commitment to scientific discovery led to the development and use of SLS, which is essential for future deep space exploration efforts. 

The Space Launch System (SLS) next to the Saturn V. The Space Launch System (SLS) next to the Saturn V.

The Path to SLS

Following the monumental successes of the Apollo program, focus shifted to low Earth orbit missions with the Space Shuttle. With a concentrated purpose on ISS support and transport, Shuttle wasn’t designed to support deep space exploration at the scale required for missions to the moon, Mars and beyond.

Recognizing these needs, NASA developed SLS to be a more flexible, advanced solution for future science missions, capable of carrying larger payloads and supporting a variety of missions, including crewed lunar landings and deep space exploration.

Boeing’s workforce at the Michoud Assembly Facility has been instrumental during the transition of space programs, showcasing a consistent, high level of engineering and technical expertise. This dedication and skill ensure that the SLS is built to the highest standards, ready to support future missions.

The SLS rocket boasts unique capabilities as a super heavy-lift vehicle, enabling it to send NASA's Orion spacecraft, astronauts, and substantial cargo directly to the moon in a single launch. The return to the lunar surface is crucial, as it allows us to study the Moon's resources, create a sustainable presence and prepare for future human exploration of Mars. The Block 1 configuration of SLS is designed to meet these immediate lunar objectives.

However, to venture farther and faster into the solar system, enhanced capabilities are essential.

The Unique Capabilities of EUS

The Block 1B configuration, featuring the more powerful Exploration Upper Stage (EUS), enables the full use of the SLS. With the ability to deliver greater payload mass, volume, and departure energy than any other rocket, the EUS-backed SLS is designed to support a variety of deep space missions, including human exploration of Mars and beyond.

The EUS replaces the Interim Cryogenic Propulsion Stage (ICPS) used in the Block 1 configuration for the Artemis I-III missions, allowing SLS to carry 40% more payload. This increase opens the door to a myriad of exploration possibilities, enabling more ambitious missions and the deployment of larger scientific instruments.

Building on the foundation of Saturn V and the Apollo missions, the EUS-enabled SLS aims to provide a reliable and powerful launch vehicle that can meet the demands of modern space exploration.

EUS-Backed SLS: Powering Future Science Missions

The EUS-enabled SLS rocket is the foundational capability for a range of future deep space science missions to the outer planets with significant reductions in flight times compared to rockets designed to launch payloads into Earth orbit. Potential missions to be launched by the EUS-enabled SLS rocket include system-validation missions to cislunar space, exploratory missions to deliver large Earth observation satellites and telescopes to space and scientific missions to the outer planets and their moons. Read more about those missions below:

  • Moon: The Artemis campaign will enable sustainable human presence on the Moon, paving the way for future exploration.
  • Venus: Missions aimed at studying Venus’ atmosphere and geology.
  • Mars: Both crewed and uncrewed missions designed to advance our knowledge of the Red Planet.
  • Outer Planets: Exploration of the gas giants and their moons to uncover more about the formation of our solar system.
  • Planetary Defense: Initiative focused on detecting and deflecting potentially hazardous asteroids to protect Earth.
  • Telescopes: Deployment of next-generation space telescopes to enhance our ability to observe distant galaxies and cosmic phenomena.
  • Beyond: Launching probes beyond our solar system in pursuit of answers to fundamental questions about the universe.

Building on History: SLS for Science & Exploration

As we look to the stars, SLS represents the next-generation of super heavy-lift launch vehicles, equipped to tackle the challenges of deep space exploration. With its unparalleled capabilities and the promise of EUS, SLS is more than a rocket; it is a gateway to endless possibilities for humanity's journey into the cosmos.

By Casey Cappa