Most likely option is as a spam-trojan, where the victim has the nasa address in their outlook address book, although a few years ago I would have leaned more towards a hand-chosen attempt to frame that address for backlash.

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And you, to whom adversity has dealt the final blow
With smiling [faces] lyin' to ye' everywhere ye' go
Turn to, and put out all your strength of arm and heart and brain
And like the Mary Ellen Carter, rise again.