As I noted in my last piece, Shuttle mission cost estimates range from $450 million and $1.5 billion per launch. What did we get for this outlay? The opinions vary, but here are a few comments summing up the Shuttle program.
John P. Shannon, Manager, Space Shuttle Program Office (from the July 20, 2011, article in Aviation Week, Space Shuttle Boss: Lessons Justified Cost)
"The U.S. gained the most capable, sophisticated spacecraft ever flown, with a safety record better than any other existing launch vehicle."
"...the tangible accomplishments in the program’s 30 years—135 flights, 852 astronauts flown to orbit, 3.5 million lb. of cargo mass delivered and 179 payloads deployed."
"Critics of the shuttle sometimes point back to hyperbole from 40 years ago. There were promises of cheap, routine access to space. However, these promises were made by a NASA that had a total of 25 human orbital spaceflights (four Mercury, 10 Gemini, 11 Apollo). It could be argued that NASA did not have the experience to make those promises at that time. The shuttle, as designed, would never approach those goals, but as the sole American human spaceflight vehicle, it served as a tremendous learning tool. Where we are today in our understanding of how to live, work and operate in the space environment is far beyond where we were after Apollo and Skylab."
Lawrence Krauss, professor and director of the Origins Project at Arizona State University (from the July 22, 2011, editorial in the Wall Street Journal, The Shuttle Was a Dud But Space Is Still Our Destiny)
"Yes, there have been highlights, and such things as the Hubble Space Telescope launch and repair missions were not only exciting, but useful. However, the real question is whether they were necessary to achieve the science goals. The initial repair mission was required because of poor engineering on the ground, which may be the fault of the decision to deploy the telescope from the space shuttle."
"Certainly, the shuttle program can't be justified on the grounds that it helped us build the International Space Station. The station is a largely useless international make-work project that was criticized by every major science organization in this country. All that can be said for its scientific justification is that it now houses a $2 billion particle-physics experiment that managed to avoid serious scientific peer review early on; otherwise it certainly would not have been recommended for funding."