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I've just finished watching the Contact movie and having had time to reflect a bit more on it, I still cannot understand why the government would not just send a second pod through the machine if they seriously did not believe Dr. Arroway. I mean, the thing cost what? Half a trillion dollars to build, why not use it at least a second time? Unlike religion there is actually a way to test the testimony and they do not have to take it on faith at all.
Note that I did not read the novel (yet) and I would appreciate it that if it is answered in the novel that somebody tells me.