"The capsule is bigger, but you couldn't tell that standing on the ground," Blevins said.īut don't be fooled - what looks similar on the outside doesn't necessarily reflect what is on the inside. Peering at the top of the SLS, you would see a similar configuration to Apollo - a capsule where the astronauts would ride, and an abort system that can pull the crew away in case of an emergency during liftoff. SLS and Saturn V both use three stages all told to heft the crew into space. Blevins said most people will identify these boosters with those that the space shuttle carried, but the SLS versions are actually about twice as tall as the space shuttle's. Riding alongside this core stage will be solid-rocket boosters to increase the SLS liftoff thrust - different from the Saturn V, which had no boosters at all. The RS-25 design is "the most efficient, most powerful, most power-per-mass type that's ever been built," Blevins said, exceeding the oxygen-kerosene fuel technology used by the Saturn V first stage's massive F-1 engines. These engines were designed for the space-shuttle program, and the first few SLS flights will rely on refurbished space shuttle engines. SLS has a core stage about the same diameter as the Saturn V's first stage, but it includes four RS-25 engines. If you were to line up the Saturn V and SLS side by side - something Blevins said he hopes to see in a future, massive museum exhibit - there are some immediately apparent differences.
NASA initially targeted a moon landing in 1967, but a series of rocket and spacecraft setbacks pushed the actual date back to July 1969, Neufeld said. Both the Apollo command and lunar modules faced development delays. "It didn't matter, fundamentally, because the spacecraft were behind expectations," Neufeld said. NASA had planned the first test flight for 1965, but it didn't end up launching until November 1967.īut the delays weren't blamed exclusively on the rocket. The Saturn V also had launch delays, although not nearly as dramatic as SLS is facing, Neufeld pointed out. (That said, NASA's Europa Clipper orbiter might launch on the SpaceX Falcon Heavy rocket, whose launch costs at just a fraction of that of SLS would save $700 million for the mission, Ars Technica added.) That's because a flight path to Europa with SLS might take only a couple of years to accomplish, instead of close to a decade, with current technology and planetary flybys. Such a vehicle could mean that a middle- or even late-career scientist building an instrument to land on Jupiter's icy moon Europa, for example, might still be working when the spacecraft lands and performs science on the surface, Blevins said.
And the rocket could blast robotic spacecraft to the outer system faster than ever before, allowing scientists to avoid the traditional circuitous route that requires spacecraft to pick up speed by flying past other planets. The SLS could launch a massive Mars sample-return mission. It's a rocket that could ferry astronauts to asteroids or to Mars, depending on government priorities.
For example, the material that lines its inner tanks is "much beefier than it needs to be" for the rocket's first robotic mission to the moon, Blevins said, because SLS will eventually send spacecraft elsewhere.
The Saturn V was imagined as a one-destination rocket, but that's not the case for SLS, which has made its design process more complex.