Mark Millar has teased that he's begun work on a 10-part spin-off to his and Frank Quitely's Jupiter's Legacy - titled Jupiter's Requiem. The writer revealed it on Twitter:
HERE IS THE NEWS pic.twitter.com/bE5Rlszgo1— Mark Millar (@mrmarkmillar) January 2, 2020
The script purposefully omits the artist of the series (unless you know someone named "TOP SECRET").
The first panel's description ("Open on Earth 50,000 years ago") infers that the series - or at least the first panel - will be a prequel to the original Jupiter's Legacy. Several years ago, Millar partnered with several artists on a 1950s set 10-issue prequel titled Jupiter's Circle.
A TV adaptation of Jupiter's Legacy is currently in production with Netflix - who acquired Jupiter's Legacy and many other of Millar's creator-owned titles in 2017.