Jason Townsend, NASA's deputy social media manager, said the agency's retention policy covers all records generated by the agency and is based on the content and use of the individual record, regardless of format. However, he noted, not all social media posts are created equal.

"Our NASA records officials have determined that social media posts are typically either duplicative content that resides elsewhere in other official, non-social media records or consists of transitory-type content that lacks significant retention value," Townsend said. "The exceptions include social media content created by high-level or otherwise prominent officials."

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