A while ago, Scott Manley made a video about the Artemis program and how NASA will expend all its Block II RS-25D engines through the SLS's first four launches. Why isn't NASA planning on putting some of them on display for their significance, like engines 2045, 2047 and 2060 as they flew on the last Shuttle Mission?

Note: NASA has done so for other engines/boosters including Saturn V hardware, but that mainly was because they had no other use as the moon program had ended.

  • 8
    $\begingroup$ Regardless of historical value, almost 100 million USD per piece are quite a good reason to use them up. $\endgroup$
    – asdfex
    Commented Jan 27, 2022 at 18:51
  • $\begingroup$ @asdfex Actually, probably quite a good reason not to use them up. Much better to expend a 10 million USD engine than a 100 million USD engine. $\endgroup$
    – WarpPrime
    Commented Jan 27, 2022 at 20:28
  • $\begingroup$ This is the contract price for the new RS-25 that are to be produced! I.e. the price to replace them with new ones. 1.8 billion for 18 more engines (extension of the existing contract, so no development costs included), minus a couple dozen millions for "related services" per engine, that is. $\endgroup$
    – asdfex
    Commented Jan 27, 2022 at 20:35
  • $\begingroup$ Uhh, any time if I read about the SLS I get itchy. $\endgroup$
    – peterh
    Commented Jan 28, 2022 at 9:46
  • 2
    $\begingroup$ I misread on first glance, and thought "Why does NASA have R2-D2s?" $\endgroup$ Commented Jan 28, 2022 at 13:57

1 Answer 1


Many SSMEs are already displayed in museums.

  • Stafford Air and Space Museum (theirs is taken apart and you can look in the pieces, very cool)
  • Stennis Space Center
  • National Air and Space Museum
  • Space Center Houston
  • Kennedy Space Center
  • US Space and Rocket Center

Sources: http://www.collectspace.com/ubb/Forum39/HTML/000329.html, personal experience

I can't lay my hand on a full list ATM, but even this partial list shows many engines that stopped being used before the end of the program. All the engines with numbers on a white background (left side of grid) were grounded long ago. There are ~20 more engines produced than shown here. Six were lost in accidents of course.

enter image description here

I personally don't like dropping them in the ocean either, but to the normal museum observer there is little visual difference between the generations of SSMEs. Any flown SSME is a valuable historical artifact.


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