After developing the J-2X engine for the upper stage of its SLS heavy-lift rocket, NASA now plans to mothball it.

Chronological Encyclopedia of Discoveries in Space cover

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NASA marches on! After developing the J-2X engine for the upper stage of its SLS heavy-lift rocket, NASA now plans to mothball it.

While the agency is actively seeking other missions for the heavy-lift Space Launch System (SLS) in the planetary science and military arenas, most of the human flights it has in sight for the big new rocket probably can be accomplished with an upper stage powered by the RL-10 engine instead of the J-2X. “The J-2X for certain [design reference missions] is somewhat overpowered,” said Todd May, NASA’s SLS program manager.

The main cause of this absurd situation is Congress, which has micro-managed the development of SLS from day one.



  • wodun

    “One way to get to that capability would be with a “dual-use upper stage” carrying three or four RL-10s. All of them would ignite to get the payload — an Orion crew capsule, in-space habitat or lunar lander — into LEO, and then some subset of that number would fire for the trans-lunar injection to send the payload toward the Moon.”

    Might as well use current launchers, smaller payloads, and in orbit assembly.

  • wade

    i will, at risk of being totally Wrong, once again say this, That bird will Never Fly. it is not meant to . it is only a venue to funnel tax money into whatever adjective that the government wants.

  • wade

    look at the trivial advancements that have been announced to the Public. have a look at the published Renderings of that entire Project. then sit back and ponder what is actually taking place.

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