No, the subject line of this message is not a joke. :-)
The IETF has formed a "TIPTOP" working group to study and adapt Internet
protocols for communication over interplanetary distances. [1] If anyone
here is interested in this topic, I encourage you read their documents
[2] and sign up for their email discussion list [3].
Thanks for your attention!
Peter
[1]
https://datatracker.ietf.org/wg/tiptop/about/
[2]
https://datatracker.ietf.org/wg/tiptop/documents/
[3]
https://mailarchive.ietf.org/arch/browse/deepspace/