Submission of publications related to NASA grant funding is required when the article has been accepted for publication. Submissions go to to PubSpace, a new NASA-branded interface to the PubMed Central repository. This should be done as soon as the article is accepted for publication. (The author manuscript version is the author's own copy of the peer reviewed manuscript, unformatted by the publisher).
For more information on how to submit NASA-funded papers to PMC, visit http://www.ncbi.nlm.nih.gov/pmc/about/submission-methods/.