I'm pretty sure you can.
We are trying to reach a person for group sales. It's been over three weeks now and no one answers any number. Does anyone have a good number for the Visitor Center? I thought they were closed down.
When it was purchased, was it a one day pass or seasonal? If purchased on line, they usually would have "a use by date." I would verify on the NASA website.
We noticed there were special tickets for Florida residents, may be your tickets are of those. I think you could visit Nasa Webpage in order to be sure.
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